1
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Zhang H, Prado Y, Alchaar R, Lehouelleur H, Cavallo M, Dang TH, Khalili A, Bossavit E, Dabard C, Ledos N, Silly MG, Madouri A, Fournier D, Utterback JK, Pierucci D, Parahyba V, Potet P, Darson D, Ithurria S, Bartłomiej Szafran, Diroll BT, Climente JI, Lhuillier E. Infrared Imaging Using Thermally Stable HgTe/CdS Nanocrystals. Nano Lett 2024. [PMID: 38608158 DOI: 10.1021/acs.nanolett.4c00907] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/14/2024]
Abstract
Transferring nanocrystals (NCs) from the laboratory environment toward practical applications has raised new challenges. HgTe appears as the most spectrally tunable infrared colloidal platform. Its low-temperature synthesis reduces the growth energy cost yet also favors sintering. Once coupled to a read-out circuit, the Joule effect aggregates the particles, leading to a poorly defined optical edge and large dark current. Here, we demonstrate that CdS shells bring the expected thermal stability (no redshift upon annealing, reduced tendency to form amalgams, and preservation of photoconduction after an atomic layer deposition process). The electronic structure of these confined particles is unveiled using k.p self-consistent simulations showing a significant exciton binding energy of ∼200 meV. After shelling, the material displays a p-type behavior that favors the generation of photoconductive gain. The latter is then used to increase the external quantum efficiency of an infrared imager, which now reaches 40% while presenting long-term stability.
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Affiliation(s)
- Huichen Zhang
- Sorbonne Université, CNRS, Institut des NanoSciences de Paris, Paris 75005, France
| | - Yoann Prado
- Sorbonne Université, CNRS, Institut des NanoSciences de Paris, Paris 75005, France
| | - Rodolphe Alchaar
- Sorbonne Université, CNRS, Institut des NanoSciences de Paris, Paris 75005, France
| | - Henri Lehouelleur
- Laboratoire de Physique et d'Etude des Matériaux, ESPCI-Paris, PSL Research University, Sorbonne Université, CNRS, Paris 75005, France
| | - Mariarosa Cavallo
- Sorbonne Université, CNRS, Institut des NanoSciences de Paris, Paris 75005, France
| | - Tung Huu Dang
- Sorbonne Université, CNRS, Institut des NanoSciences de Paris, Paris 75005, France
- Laboratoire de Physique de l'Ecole normale supérieure, ENS, Université PSL, CNRS, Sorbonne Université, Sorbonne Paris Cité, Paris 75005, France
| | - Adrien Khalili
- Sorbonne Université, CNRS, Institut des NanoSciences de Paris, Paris 75005, France
| | - Erwan Bossavit
- Sorbonne Université, CNRS, Institut des NanoSciences de Paris, Paris 75005, France
- Synchrotron SOLEIL, Saint-Aubin 91190, France
| | - Corentin Dabard
- Laboratoire de Physique et d'Etude des Matériaux, ESPCI-Paris, PSL Research University, Sorbonne Université, CNRS, Paris 75005, France
| | - Nicolas Ledos
- Sorbonne Université, CNRS, Institut des NanoSciences de Paris, Paris 75005, France
| | | | - Ali Madouri
- Centre de Nanosciences et de Nanotechnologies, CNRS, Université Paris-Saclay, C2N, Palaiseau 91120, France
| | - Daniele Fournier
- Sorbonne Université, CNRS, Institut des NanoSciences de Paris, Paris 75005, France
| | - James K Utterback
- Sorbonne Université, CNRS, Institut des NanoSciences de Paris, Paris 75005, France
| | - Debora Pierucci
- Sorbonne Université, CNRS, Institut des NanoSciences de Paris, Paris 75005, France
| | - Victor Parahyba
- New Imaging Technologies SA, Verrières le Buisson 91370, France
| | - Pierre Potet
- New Imaging Technologies SA, Verrières le Buisson 91370, France
| | - David Darson
- Laboratoire de Physique de l'Ecole normale supérieure, ENS, Université PSL, CNRS, Sorbonne Université, Sorbonne Paris Cité, Paris 75005, France
| | - Sandrine Ithurria
- Laboratoire de Physique et d'Etude des Matériaux, ESPCI-Paris, PSL Research University, Sorbonne Université, CNRS, Paris 75005, France
| | - Bartłomiej Szafran
- Faculty of Physics and Applied Computer Science, AGH University, Kraków PL-30-059, Poland
| | - Benjamin T Diroll
- Center for Nanoscale Materials, Argonne National Laboratory, Lemont, Illinois 60439, United States
| | - Juan I Climente
- Departament de Quimica Fisica i Analitica, Universitat Jaume I, Castello de la Plana E-12080, Spain
| | - Emmanuel Lhuillier
- Sorbonne Université, CNRS, Institut des NanoSciences de Paris, Paris 75005, France
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2
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Ali A, Cruguel H, Giangrisostomi E, Ovsyannikov R, Silly MG, Dudy L, Cappel UB, Lhuillier E, Witkowski N, Johansson FOL. The Electronic Impact of Light-Induced Degradation in CsPbBr 3 Perovskite Nanocrystals at Gold Interfaces. J Phys Chem Lett 2024; 15:3721-3727. [PMID: 38546374 PMCID: PMC11017319 DOI: 10.1021/acs.jpclett.4c00139] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2024] [Revised: 03/15/2024] [Accepted: 03/19/2024] [Indexed: 04/12/2024]
Abstract
The understanding of the interfacial properties in perovskite devices under irradiation is crucial for their engineering. In this study we show how the electronic structure of the interface between CsPbBr3 perovskite nanocrystals (PNCs) and Au is affected by irradiation of X-rays, near-infrared (NIR), and ultraviolet (UV) light. The effects of X-ray and light exposure could be differentiated by employing low-dose X-ray photoelectron spectroscopy (XPS). Apart from the common degradation product of metallic lead (Pb0), a new intermediate component (Pbint) was identified in the Pb 4f XPS spectra after exposure to high intensity X-rays or UV light. The Pbint component is determined to be monolayer metallic Pb on-top of the Au substrate from underpotential deposition (UPD) of Pb induced from the breaking of the perovskite structure allowing for migration of Pb2+.
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Affiliation(s)
- Azmat Ali
- Sorbonne
Université, CNRS, Institut des Nanosciences
de Paris, INSP, F-75005, Paris, France
| | - Herve Cruguel
- Sorbonne
Université, CNRS, Institut des Nanosciences
de Paris, INSP, F-75005, Paris, France
| | - Erika Giangrisostomi
- Institute
Methods and Instrumentation for Synchrotron Radiation Research PS-ISRR, Helmholtz Berlin für Materialien und Energie, Albert-Einstein-Straße 15, 12489, Berlin, Germany
| | - Ruslan Ovsyannikov
- Institute
Methods and Instrumentation for Synchrotron Radiation Research PS-ISRR, Helmholtz Berlin für Materialien und Energie, Albert-Einstein-Straße 15, 12489, Berlin, Germany
| | - Mathieu G. Silly
- Synchrotron
SOLEIL, l‘Orme des Merisiers, Saint-Aubin, Boîte Postale 48, 9119, Gif-sur-Yvette Cedex, France
| | - Lenart Dudy
- Synchrotron
SOLEIL, l‘Orme des Merisiers, Saint-Aubin, Boîte Postale 48, 9119, Gif-sur-Yvette Cedex, France
| | - Ute B. Cappel
- Division
of Applied Physical Chemistry, Department of Chemistry, KTH − Royal Institute of Technology, SE-100 44 Stockholm, Sweden
| | - Emmanuel Lhuillier
- Sorbonne
Université, CNRS, Institut des Nanosciences
de Paris, INSP, F-75005, Paris, France
| | - Nadine Witkowski
- Sorbonne
Université, CNRS, Institut des Nanosciences
de Paris, INSP, F-75005, Paris, France
| | - Fredrik O. L. Johansson
- Sorbonne
Université, CNRS, Institut des Nanosciences
de Paris, INSP, F-75005, Paris, France
- Division
of Applied Physical Chemistry, Department of Chemistry, KTH − Royal Institute of Technology, SE-100 44 Stockholm, Sweden
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3
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Vélez-Fort E, Ohresser P, Silly MG, Bonvoisin J, Silly F. Structural and Magnetic Properties of a Drop-Cast C 54H 34Br 4CuO 4 β-Diketonato Complex Film on a Graphite Surface. Langmuir 2023; 39:14000-14005. [PMID: 37656672 DOI: 10.1021/acs.langmuir.3c01684] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/03/2023]
Abstract
The structural and magnetic properties of a drop-cast film of flat C54H34Br4CuO4, a β-diketonato complex functionalized with bromine atoms, on a graphite surface are investigated using scanning tunneling microscopy, synchrotron X-ray absorption spectroscopy, and X-ray magnetic circular dichroism. Experimental measurements reveal that the Cu-complexes preferentially lay flat on the graphite surface. The magnetic hysteresis loops show that the organic thin film remains paramagnetic at 2 K with an easy axis of magnetization perpendicular to the graphite surface and is therefore perpendicular to the plane of the Cu-complex skeleton.
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Affiliation(s)
- Emilio Vélez-Fort
- European Synchrotron Radiation Facility (ESRF), Avenue des Martyrs 71, 38043 Grenoble, France
| | - Philippe Ohresser
- Synchrotron SOLEIL, L'Orme des Merisiers, F-91190 Saint-Aubin, France
| | - Mathieu G Silly
- Synchrotron SOLEIL, L'Orme des Merisiers, F-91190 Saint-Aubin, France
| | - Jacques Bonvoisin
- CEMES, CNRS UPR 8011, Université de Toulouse, 29 Rue Jeanne Marvig, B.P. 94347, 31055 Toulouse Cedex 4, France
| | - Fabien Silly
- Université Paris-Saclay, CEA, CNRS, SPEC, TITANS, F-91191 Gif sur Yvette, France
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4
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Cavallo M, Alchaar R, Bossavit E, Zhang H, Dang TH, Khalili A, Prado Y, Silly MG, Utterback JK, Ithurria S, Dudin P, Avila J, Pierucci D, Lhuillier E. Inside a nanocrystal-based photodiode using photoemission microscopy. Nanoscale 2023. [PMID: 37158270 DOI: 10.1039/d3nr00999h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
As nanocrystal-based devices gain maturity, a comprehensive understanding of their electronic structure is necessary for further optimization. Most spectroscopic techniques typically examine pristine materials and disregard the coupling of the active material to its actual environment, the influence of an applied electric field, and possible illumination effects. Therefore, it is critical to develop tools that can probe device in situ and operando. Here, we explore photoemission microscopy as a tool to unveil the energy landscape of a HgTe NC-based photodiode. We propose a planar diode stack to facilitate surface-sensitive photoemission measurements. We demonstrate that the method gives direct quantification of the diode's built-in voltage. Furthermore, we discuss how it is affected by particle size and illumination. We show that combining SnO2 and Ag2Te as electron and hole transport layers is better suited for extended-short-wave infrared materials than materials with larger bandgaps. We also identify the effect of photodoping over the SnO2 layer and propose a strategy to overcome it. Given its simplicity, the method appears to be of utmost interest for screening diode design strategies.
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Affiliation(s)
- Mariarosa Cavallo
- Sorbonne Université, CNRS, Institut des NanoSciences de Paris, INSP, F-75005 Paris, France.
| | - Rodolphe Alchaar
- Sorbonne Université, CNRS, Institut des NanoSciences de Paris, INSP, F-75005 Paris, France.
| | - Erwan Bossavit
- Sorbonne Université, CNRS, Institut des NanoSciences de Paris, INSP, F-75005 Paris, France.
- Synchrotron SOLEIL, L'Orme des Merisiers, Départementale 128, 91190 Saint-Aubin, France
| | - Huichen Zhang
- Sorbonne Université, CNRS, Institut des NanoSciences de Paris, INSP, F-75005 Paris, France.
| | - Tung Huu Dang
- Sorbonne Université, CNRS, Institut des NanoSciences de Paris, INSP, F-75005 Paris, France.
| | - Adrien Khalili
- Sorbonne Université, CNRS, Institut des NanoSciences de Paris, INSP, F-75005 Paris, France.
| | - Yoann Prado
- Sorbonne Université, CNRS, Institut des NanoSciences de Paris, INSP, F-75005 Paris, France.
| | - Mathieu G Silly
- Synchrotron SOLEIL, L'Orme des Merisiers, Départementale 128, 91190 Saint-Aubin, France
| | - James K Utterback
- Sorbonne Université, CNRS, Institut des NanoSciences de Paris, INSP, F-75005 Paris, France.
| | - Sandrine Ithurria
- Laboratoire de Physique et d'Etude des Matériaux, ESPCI-Paris, PSL Research University, Sorbonne Université Univ Paris 06, CNRS UMR 8213, 10 rue Vauquelin, 75005 Paris, France
| | - Pavel Dudin
- Synchrotron SOLEIL, L'Orme des Merisiers, Départementale 128, 91190 Saint-Aubin, France
| | - José Avila
- Synchrotron SOLEIL, L'Orme des Merisiers, Départementale 128, 91190 Saint-Aubin, France
| | - Debora Pierucci
- Sorbonne Université, CNRS, Institut des NanoSciences de Paris, INSP, F-75005 Paris, France.
| | - Emmanuel Lhuillier
- Sorbonne Université, CNRS, Institut des NanoSciences de Paris, INSP, F-75005 Paris, France.
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5
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Cavallo M, Bossavit E, Zhang H, Dabard C, Dang TH, Khalili A, Abadie C, Alchaar R, Mastrippolito D, Prado Y, Becerra L, Rosticher M, Silly MG, Utterback JK, Ithurria S, Avila J, Pierucci D, Lhuillier E. Mapping the Energy Landscape from a Nanocrystal-Based Field Effect Transistor under Operation Using Nanobeam Photoemission Spectroscopy. Nano Lett 2023; 23:1363-1370. [PMID: 36692377 DOI: 10.1021/acs.nanolett.2c04637] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
As the field of nanocrystal-based optoelectronics matures, more advanced techniques must be developed in order to reveal the electronic structure of nanocrystals, particularly with device-relevant conditions. So far, most of the efforts have been focused on optical spectroscopy, and electrochemistry where an absolute energy reference is required. Device optimization requires probing not only the pristine material but also the material in its actual environment (i.e., surrounded by a transport layer and an electrode, in the presence of an applied electric field). Here, we explored the use of photoemission microscopy as a strategy for operando investigation of NC-based devices. We demonstrate that the method can be applied to a variety of materials and device geometries. Finally, we show that it provides direct access to the metal-semiconductor interface band bending as well as the distance over which the gate effect propagates in field-effect transistors.
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Affiliation(s)
- Mariarosa Cavallo
- Sorbonne Université, CNRS, Institut des NanoSciences de Paris, INSP, F-75005 Paris, France
| | - Erwan Bossavit
- Sorbonne Université, CNRS, Institut des NanoSciences de Paris, INSP, F-75005 Paris, France
- Synchrotron SOLEIL, L'Orme des Merisiers, Départementale 128, 91190 Saint-Aubin, France
| | - Huichen Zhang
- Sorbonne Université, CNRS, Institut des NanoSciences de Paris, INSP, F-75005 Paris, France
| | - Corentin Dabard
- Laboratoire de Physique et d'Etude des Matériaux, ESPCI-Paris, PSL Research University, Sorbonne Université Univ Paris 06, CNRS UMR 8213, 10 rue Vauquelin, 75005 Paris, France
| | - Tung Huu Dang
- Sorbonne Université, CNRS, Institut des NanoSciences de Paris, INSP, F-75005 Paris, France
- Laboratoire de Physique de l'Ecole normale supérieure, ENS, Université PSL, CNRS, Sorbonne Université, Université Paris-Diderot, Sorbonne Paris Cité, 75005 Paris, France
| | - Adrien Khalili
- Sorbonne Université, CNRS, Institut des NanoSciences de Paris, INSP, F-75005 Paris, France
| | - Claire Abadie
- Sorbonne Université, CNRS, Institut des NanoSciences de Paris, INSP, F-75005 Paris, France
| | - Rodolphe Alchaar
- Sorbonne Université, CNRS, Institut des NanoSciences de Paris, INSP, F-75005 Paris, France
| | - Dario Mastrippolito
- Department of Physical and Chemical Sciences (DSFC), University of L'Aquila, Via Vetoio, 67100 L'Aquila, Italy
| | - Yoann Prado
- Sorbonne Université, CNRS, Institut des NanoSciences de Paris, INSP, F-75005 Paris, France
| | - Loïc Becerra
- Sorbonne Université, CNRS, Institut des NanoSciences de Paris, INSP, F-75005 Paris, France
| | - Michael Rosticher
- Laboratoire de Physique de l'Ecole normale supérieure, ENS, Université PSL, CNRS, Sorbonne Université, Université Paris-Diderot, Sorbonne Paris Cité, 75005 Paris, France
| | - Mathieu G Silly
- Synchrotron SOLEIL, L'Orme des Merisiers, Départementale 128, 91190 Saint-Aubin, France
| | - James K Utterback
- Sorbonne Université, CNRS, Institut des NanoSciences de Paris, INSP, F-75005 Paris, France
| | - Sandrine Ithurria
- Laboratoire de Physique et d'Etude des Matériaux, ESPCI-Paris, PSL Research University, Sorbonne Université Univ Paris 06, CNRS UMR 8213, 10 rue Vauquelin, 75005 Paris, France
| | - José Avila
- Synchrotron SOLEIL, L'Orme des Merisiers, Départementale 128, 91190 Saint-Aubin, France
| | - Debora Pierucci
- Centre de Nanosciences et de Nanotechnologies, CNRS, Univ. Paris-Sud, Université Paris-Saclay, 10 Boulevard Thomas Gobert, 91120 Palaiseau, France
| | - Emmanuel Lhuillier
- Sorbonne Université, CNRS, Institut des NanoSciences de Paris, INSP, F-75005 Paris, France
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6
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Arrigo R, Aureau D, Bhatt P, Buckingham MA, Counter JJC, D'Acunto G, Davies PR, Evans DA, Flavell WR, Gibson JS, Guan S, Held G, Isaacs M, Kahk JM, Kastorp CFP, Kersell H, Krizan A, Large AI, Lindsay R, Lischner J, Lömker P, Morgan D, Nemšák S, Nilsson A, Payne D, Reed BP, Renault O, Rupprechter G, Shard AG, Shozi M, Silly MG, Skinner WSJ, Solal F, Stoerzinger KA, Suzer S, Velasco Vélez JJ, Walker M, Weatherup RS. In situ methods: discoveries and challenges: general discussion. Faraday Discuss 2022; 236:219-266. [PMID: 35968885 DOI: 10.1039/d2fd90025d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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7
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Arrigo R, Aureau D, Ban L, Bartels-Rausch T, Counter JJC, Davies PR, Dell'Angela M, Dowhyj M, Evans A, Flavell W, Held G, Kastorp CFP, Lindsay R, Nilsson A, Redekop E, Renault O, Rupprechter G, Silly MG, Suzer S. Time resolved surface analysis (kinetic and molecular time scales): general discussion. Faraday Discuss 2022; 236:510-527. [PMID: 35861561 DOI: 10.1039/d2fd90029g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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8
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Silly MG. High resolution and time resolved photoemission spectroscopy for developing more efficient materials to reduce energy consumption and increase renewable energy production. EPJ Web Conf 2022. [DOI: 10.1051/epjconf/202227301013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022] Open
Abstract
Due to the increase of energy consumption and the resulting ecological challenge, a collective awareness leads to the development of renewable energies and more efficient materials to increase the green energy production. Development of efficient photovoltaic materials is very closely related to their chemical and electronic properties. A better knowledge of these imbricated properties is needed, in addition to a better comprehension of their interplay with charge transport mechanisms. Exciton creation and recombination processes, charge transfer and charge collection processes take place at the surface and interface of the photoactive materials. Photoemission spectroscopy as chemical specific and surface sensitive spectroscopic technique is a method of choice on the study of physical phenomena at the origin of photoconversion efficiency. Time resolved photoemission spectroscopy has been recently renewed interest covering time scale from fs to more than seconds. It permits to probe the dynamics of relaxation of photoexcited charges and determine their lifetime. It finds application in various materials used in solar photovoltaics. In this paper, we define the physical and chemical properties determined by the combination of high resolution and time resolved photoemission spectroscopy. We show examples dealing with the development of renewable energy and energy consumption reduction in agreement with the current ecological trend for a better future.
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9
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Clark PCJ, Lewis NK, Ke JCR, Ahumada-Lazo R, Chen Q, Neo DCJ, Gaulding EA, Pach GF, Pis I, Silly MG, Flavell WR. Surface band bending and carrier dynamics in colloidal quantum dot solids. Nanoscale 2021; 13:17793-17806. [PMID: 34668501 DOI: 10.1039/d1nr05436h] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Band bending in colloidal quantum dot (CQD) solids has become important in driving charge carriers through devices. This is typically a result of band alignments at junctions in the device. Whether band bending is intrinsic to CQD solids, i.e. is band bending present at the surface-vacuum interface, has previously been unanswered. Here we use photoemission surface photovoltage measurements to show that depletion regions are present at the surface of n and p-type CQD solids with various ligand treatments (EDT, MPA, PbI2, MAI/PbI2). Using laser-pump photoemission-probe time-resolved measurements, we show that the timescale of carrier dynamics in the surface of CQD solids can vary over at least 6 orders of magnitude, with the fastest dynamics on the order of microseconds in PbS-MAI/PbI2 solids and on the order of seconds for PbS-MPA and PbS-PbI2. By investigating the surface chemistry of the solids, we find a correlation between the carrier dynamics timescales and the presence of oxygen contaminants, which we suggest are responsible for the slower dynamics due to deep trap formation.
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Affiliation(s)
- Pip C J Clark
- Department of Physics and Astronomy and the Photon Science Institute, The University of Manchester, Manchester M13 9PL, UK.
| | - Nathan K Lewis
- Department of Physics and Astronomy and the Photon Science Institute, The University of Manchester, Manchester M13 9PL, UK.
| | - Jack Chun-Ren Ke
- Department of Physics and Astronomy and the Photon Science Institute, The University of Manchester, Manchester M13 9PL, UK.
| | - Ruben Ahumada-Lazo
- Department of Physics and Astronomy and the Photon Science Institute, The University of Manchester, Manchester M13 9PL, UK.
| | - Qian Chen
- Department of Materials, The University of Manchester, Manchester M13 9PL, UK
| | - Darren C J Neo
- Department of Chemistry, University of California, Irvine, Irvine, California 92697, USA
| | | | - Gregory F Pach
- National Renewable Energy Laboratory, Golden, CO 80401, USA
| | - Igor Pis
- Laboratorio TASC, IOM CNR, S.S. 14 km 163.5, 34149 Basovizza, Trieste, Italy
- Elettra-Sincrotrone Trieste S.C.p.A., S. S. 14 Km 163.5, 34149 Basovizza, Trieste, Italy
| | - Mathieu G Silly
- Synchrotron SOLEIL, BP 48, Saint-Aubin, F91192 Gif sur Yvette CEDEX, France
| | - Wendy R Flavell
- Department of Physics and Astronomy and the Photon Science Institute, The University of Manchester, Manchester M13 9PL, UK.
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10
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Qu J, Rastogi P, Gréboval C, Lagarde D, Chu A, Dabard C, Khalili A, Cruguel H, Robert C, Xu XZ, Ithurria S, Silly MG, Ferré S, Marie X, Lhuillier E. Electroluminescence from HgTe Nanocrystals and Its Use for Active Imaging. Nano Lett 2020; 20:6185-6190. [PMID: 32662652 DOI: 10.1021/acs.nanolett.0c02557] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Mercury telluride (HgTe) nanocrystals are among the most versatile infrared (IR) materials with the absorption of lowest energy optical absorption which can be tuned from the visible to the terahertz range. Therefore, they have been extensively considered as near IR emitters and as absorbers for low-cost IR detectors. However, the electroluminescence of HgTe remains poorly investigated despite its ability to go toward longer wavelengths compared to traditional lead sulfide (PbS). Here, we demonstrate a light-emitting diode (LED) based on an indium tin oxide (ITO)/zinc oxide (ZnO)/ZnO-HgTe/PbS/gold-stacked structure, where the emitting layer consists of a ZnO/HgTe bulk heterojunction which drives the charge balance in the system. This LED has low turn-on voltage, long lifetime, and high brightness. Finally, we conduct short wavelength infrared (SWIR) active imaging, where illumination is obtained from a HgTe NC-based LED, and demonstrate moisture detection.
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Affiliation(s)
- Junling Qu
- Institut des NanoSciences de Paris, Sorbonne Université, CNRS, INSP, F-75005 Paris, France
| | - Prachi Rastogi
- Institut des NanoSciences de Paris, Sorbonne Université, CNRS, INSP, F-75005 Paris, France
| | - Charlie Gréboval
- Institut des NanoSciences de Paris, Sorbonne Université, CNRS, INSP, F-75005 Paris, France
| | - Delphine Lagarde
- INSA-CNRS-UPS, LPCNO, Université de Toulouse, 31000, Toulouse, France
| | - Audrey Chu
- Institut des NanoSciences de Paris, Sorbonne Université, CNRS, INSP, F-75005 Paris, France
| | - Corentin Dabard
- Institut des NanoSciences de Paris, Sorbonne Université, CNRS, INSP, F-75005 Paris, France
| | - Adrien Khalili
- Institut des NanoSciences de Paris, Sorbonne Université, CNRS, INSP, F-75005 Paris, France
| | - Hervé Cruguel
- Institut des NanoSciences de Paris, Sorbonne Université, CNRS, INSP, F-75005 Paris, France
| | - Cédric Robert
- INSA-CNRS-UPS, LPCNO, Université de Toulouse, 31000, Toulouse, France
| | - Xiang Zhen Xu
- Laboratoire de Physique et d'Etude des Matériaux, ESPCI-Paris, PSL Research University, Sorbonne Université Univ Paris 06, CNRS UMR 8213, 10 rue Vauquelin 75005 Paris, France
| | - Sandrine Ithurria
- Laboratoire de Physique et d'Etude des Matériaux, ESPCI-Paris, PSL Research University, Sorbonne Université Univ Paris 06, CNRS UMR 8213, 10 rue Vauquelin 75005 Paris, France
| | - Mathieu G Silly
- Synchrotron-SOLEIL, Saint-Aubin, BP48, F91192 Gif sur Yvette, Cedex, France
| | - Simon Ferré
- New Imaging Technologies SA, 1 impasse de la Noisette 91370 Verrières le Buisson, France
| | - Xavier Marie
- INSA-CNRS-UPS, LPCNO, Université de Toulouse, 31000, Toulouse, France
| | - Emmanuel Lhuillier
- Institut des NanoSciences de Paris, Sorbonne Université, CNRS, INSP, F-75005 Paris, France
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11
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Rastogi P, Chu A, Gréboval C, Qu J, Noumbé UN, Chee SS, Goyal M, Khalili A, Xu XZ, Cruguel H, Ithurria S, Gallas B, Dayen JF, Dudy L, Silly MG, Patriarche G, Degiron A, Vincent G, Lhuillier E. Pushing Absorption of Perovskite Nanocrystals into the Infrared. Nano Lett 2020; 20:3999-4006. [PMID: 32283029 DOI: 10.1021/acs.nanolett.0c01302] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
To date, defect-tolerance electronic structure of lead halide perovskite nanocrystals is limited to an optical feature in the visible range. Here, we demonstrate that IR sensitization of formamidinium lead iodine (FAPI) nanocrystal array can be obtained by its doping with PbS nanocrystals. In this hybrid array, absorption comes from the PbS nanocrystals while transport is driven by the perovskite which reduces the dark current compared to pristine PbS. In addition, we fabricate a field-effect transistor using a high capacitance ionic glass made of hybrid FAPI/PbS nanocrystal arrays. We show that the hybrid material has an n-type nature with an electron mobility of 2 × 10-3 cm2 V-1 s-1. However, the dark current reduction is mostly balanced by a loss of absorption. To overcome this limitation, we couple the FAPI/PbS hybrid to a guided mode resonator that can enhance the infrared light absorption.
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Affiliation(s)
- Prachi Rastogi
- Institut des NanoSciences de Paris, INSP, Sorbonne Université, CNRS, F-75005 Paris, France
| | - Audrey Chu
- Institut des NanoSciences de Paris, INSP, Sorbonne Université, CNRS, F-75005 Paris, France
| | - Charlie Gréboval
- Institut des NanoSciences de Paris, INSP, Sorbonne Université, CNRS, F-75005 Paris, France
| | - Junling Qu
- Institut des NanoSciences de Paris, INSP, Sorbonne Université, CNRS, F-75005 Paris, France
| | | | - Sang-Soo Chee
- Institut des NanoSciences de Paris, INSP, Sorbonne Université, CNRS, F-75005 Paris, France
| | - Mayank Goyal
- Institut des NanoSciences de Paris, INSP, Sorbonne Université, CNRS, F-75005 Paris, France
| | - Adrien Khalili
- Institut des NanoSciences de Paris, INSP, Sorbonne Université, CNRS, F-75005 Paris, France
| | - Xiang Zhen Xu
- Laboratoire de Physique et d'Etude des Matériaux, ESPCI-Paris, PSL Research University, Sorbonne Université Univ Paris 06, CNRS UMR 8213, 10 rue Vauquelin 75005 Paris, France
| | - Hervé Cruguel
- Institut des NanoSciences de Paris, INSP, Sorbonne Université, CNRS, F-75005 Paris, France
| | - Sandrine Ithurria
- Laboratoire de Physique et d'Etude des Matériaux, ESPCI-Paris, PSL Research University, Sorbonne Université Univ Paris 06, CNRS UMR 8213, 10 rue Vauquelin 75005 Paris, France
| | - Bruno Gallas
- Institut des NanoSciences de Paris, INSP, Sorbonne Université, CNRS, F-75005 Paris, France
| | - Jean-Francois Dayen
- Université de Strasbourg, IPCMS-CNRS UMR 7504, 23 Rue du Loess, 67034 Strasbourg, France
| | - Lenart Dudy
- Synchrotron-SOLEIL, Saint-Aubin, BP48, F91192 Gif sur Yvette Cedex, France
| | - Mathieu G Silly
- Synchrotron-SOLEIL, Saint-Aubin, BP48, F91192 Gif sur Yvette Cedex, France
| | - Gilles Patriarche
- Centre de Nanosciences et de Nanotechnologies, CNRS, University of Paris-Sud, Université Paris-Saclay, C2N, Marcoussis 91460, France
| | - Aloyse Degiron
- Laboratoire Matériaux et Phénomènes Quantiques, Université de Paris, CNRS, 75013 Paris, France
| | - Grégory Vincent
- ONERA - The French Aerospace Lab, 6, chemin de la Vauve aux Granges, BP 80100, 91123 Palaiseau, France
| | - Emmanuel Lhuillier
- Institut des NanoSciences de Paris, INSP, Sorbonne Université, CNRS, F-75005 Paris, France
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12
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Chu A, Martinez B, Ferré S, Noguier V, Gréboval C, Livache C, Qu J, Prado Y, Casaretto N, Goubet N, Cruguel H, Dudy L, Silly MG, Vincent G, Lhuillier E. HgTe Nanocrystals for SWIR Detection and Their Integration up to the Focal Plane Array. ACS Appl Mater Interfaces 2019; 11:33116-33123. [PMID: 31426628 DOI: 10.1021/acsami.9b09954] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Infrared applications remain too often a niche market due to their prohibitive cost. Nanocrystals offer an interesting alternative to reach cost disruption especially in the short-wave infrared (SWIR, λ < 1.7 μm) where material maturity is now high. Two families of materials are candidate for SWIR photoconduction: lead and mercury chalcogenides. Lead sulfide typically benefits from all the development made for a wider band gap such as the one made for solar cells, while HgTe takes advantage of the development relative to mid-wave infrared detectors. Here, we make a fair comparison of the two material detection properties in the SWIR and discuss the material stability. At such wavelengths, studies have been mostly focused on PbS rather than on HgTe, therefore we focus in the last part of the discussion on the effect of surface chemistry on the electronic spectrum of HgTe nanocrystals. We unveil that tuning the capping ligands is a viable strategy to adjust the material from the p-type to ambipolar. Finally, HgTe nanocrystals are integrated into multipixel devices to quantize spatial homogeneity and onto read-out circuits to obtain a fast and sensitive infrared laser beam profile.
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Affiliation(s)
- Audrey Chu
- Sorbonne Université, CNRS, Institut des NanoSciences de Paris, INSP , F-75005 Paris , France
- ONERA-The French Aerospace Lab , Chemin de la Hunière, BP 80100 , F-91123 Palaiseau , France
| | - Bertille Martinez
- Sorbonne Université, CNRS, Institut des NanoSciences de Paris, INSP , F-75005 Paris , France
- Laboratoire de Physique et d'Étude des Matériaux , ESPCI Paris PSL Research University, Sorbonne Université Univ Paris 06, CNRS , 10 rue Vauquelin 75005 Paris , France
| | - Simon Ferré
- New Imaging Technologies SA , 1 impasse de la Noisette 91370 Verrières le Buisson , France
| | - Vincent Noguier
- New Imaging Technologies SA , 1 impasse de la Noisette 91370 Verrières le Buisson , France
| | - Charlie Gréboval
- Sorbonne Université, CNRS, Institut des NanoSciences de Paris, INSP , F-75005 Paris , France
| | - Clément Livache
- Sorbonne Université, CNRS, Institut des NanoSciences de Paris, INSP , F-75005 Paris , France
- Laboratoire de Physique et d'Étude des Matériaux , ESPCI Paris PSL Research University, Sorbonne Université Univ Paris 06, CNRS , 10 rue Vauquelin 75005 Paris , France
| | - Junling Qu
- Sorbonne Université, CNRS, Institut des NanoSciences de Paris, INSP , F-75005 Paris , France
| | - Yoann Prado
- Sorbonne Université, CNRS, Institut des NanoSciences de Paris, INSP , F-75005 Paris , France
| | - Nicolas Casaretto
- Sorbonne Université, CNRS, Institut des NanoSciences de Paris, INSP , F-75005 Paris , France
| | - Nicolas Goubet
- Sorbonne Université, CNRS, Institut des NanoSciences de Paris, INSP , F-75005 Paris , France
- Sorbonne Université, CNRS, De la Molécule aux Nano-objets: Réactivité, Interactions et Spectroscopies, MONARIS , F-75005 Paris , France
| | - Hervé Cruguel
- Sorbonne Université, CNRS, Institut des NanoSciences de Paris, INSP , F-75005 Paris , France
| | - Lenart Dudy
- Synchrotron-SOLEIL , Saint-Aubin, BP48 , F91192 Gif sur Yvette Cedex , France
| | - Mathieu G Silly
- Synchrotron-SOLEIL , Saint-Aubin, BP48 , F91192 Gif sur Yvette Cedex , France
| | - Grégory Vincent
- ONERA-The French Aerospace Lab , Chemin de la Hunière, BP 80100 , F-91123 Palaiseau , France
| | - Emmanuel Lhuillier
- Sorbonne Université, CNRS, Institut des NanoSciences de Paris, INSP , F-75005 Paris , France
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13
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Dufour M, Izquierdo E, Livache C, Martinez B, Silly MG, Pons T, Lhuillier E, Delerue C, Ithurria S. Doping as a Strategy to Tune Color of 2D Colloidal Nanoplatelets. ACS Appl Mater Interfaces 2019; 11:10128-10134. [PMID: 30777752 DOI: 10.1021/acsami.8b18650] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Among colloidal nanocrystals, 2D nanoplatelets (NPLs) made of II-VI compounds appear as a special class of emitters with an especially narrow photoluminescence signal. However, the PL signal in the case of NPLs is only tunable by a discrete step. Here, we demonstrate that doping is a viable path to finely tune the color of these NPLs from green to red, making them extremely interesting as phosphors for wide-gamut display. In addition, using a combination of luminescence spectroscopy, tight-binding simulation, transport, and photoemission, we provide a consistent picture for the Ag+-doped CdSe NPLs. The Ag-activated state is strongly bound and located 340 meV above the valence band of the bulk material. The Ag dopant induces a relative shift of the Fermi level toward the valence band by up to 400 meV but preserves the n-type nature of the material.
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Affiliation(s)
- Marion Dufour
- Laboratoire de Physique et d'Etude des Matériaux , ESPCI-Paris, PSL Research University, Sorbonne Université UPMC Univ Paris 06, CNRS , 10 rue Vauquelin , 75005 Paris , France
| | - Eva Izquierdo
- Laboratoire de Physique et d'Etude des Matériaux , ESPCI-Paris, PSL Research University, Sorbonne Université UPMC Univ Paris 06, CNRS , 10 rue Vauquelin , 75005 Paris , France
| | - Clément Livache
- Laboratoire de Physique et d'Etude des Matériaux , ESPCI-Paris, PSL Research University, Sorbonne Université UPMC Univ Paris 06, CNRS , 10 rue Vauquelin , 75005 Paris , France
- Sorbonne Université, CNRS, Institut des nanosciences de Paris, INSP , F-75005 Paris , France
| | - Bertille Martinez
- Laboratoire de Physique et d'Etude des Matériaux , ESPCI-Paris, PSL Research University, Sorbonne Université UPMC Univ Paris 06, CNRS , 10 rue Vauquelin , 75005 Paris , France
- Sorbonne Université, CNRS, Institut des nanosciences de Paris, INSP , F-75005 Paris , France
| | - Mathieu G Silly
- Synchrotron-SOLEIL , Saint-Aubin, BP48, F91192 Gif-sur-Yvette , France
| | - Thomas Pons
- Laboratoire de Physique et d'Etude des Matériaux , ESPCI-Paris, PSL Research University, Sorbonne Université UPMC Univ Paris 06, CNRS , 10 rue Vauquelin , 75005 Paris , France
| | - Emmanuel Lhuillier
- Sorbonne Université, CNRS, Institut des nanosciences de Paris, INSP , F-75005 Paris , France
| | - Christophe Delerue
- Université de Lille, CNRS, Centrale Lille, ISEN, Université de Valenciennes, UMR 8520-IEMN , 59000 Lille , France
| | - Sandrine Ithurria
- Laboratoire de Physique et d'Etude des Matériaux , ESPCI-Paris, PSL Research University, Sorbonne Université UPMC Univ Paris 06, CNRS , 10 rue Vauquelin , 75005 Paris , France
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14
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Livache C, Goubet N, Martinez B, Jagtap A, Qu J, Ithurria S, Silly MG, Dubertret B, Lhuillier E. Band Edge Dynamics and Multiexciton Generation in Narrow Band Gap HgTe Nanocrystals. ACS Appl Mater Interfaces 2018; 10:11880-11887. [PMID: 29578678 DOI: 10.1021/acsami.8b00153] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Mercury chalcogenide nanocrystals and especially HgTe appear as an interesting platform for the design of low cost mid-infrared (mid-IR) detectors. Nevertheless, their electronic structure and transport properties remain poorly understood, and some critical aspects such as the carrier relaxation dynamics at the band edge have been pushed under the rug. Some of the previous reports on dynamics are setup-limited, and all of them have been obtained using photon energy far above the band edge. These observations raise two main questions: (i) what are the carrier dynamics at the band edge and (ii) should we expect some additional effect (multiexciton generation (MEG)) as such narrow band gap materials are excited far above the band edge? To answer these questions, we developed a high-bandwidth setup that allows us to understand and compare the carrier dynamics resonantly pumped at the band edge in the mid-IR and far above the band edge. We demonstrate that fast (>50 MHz) photoresponse can be obtained even in the mid-IR and that MEG is occurring in HgTe nanocrystal arrays with a threshold around 3 times the band edge energy. Furthermore, the photoresponse can be effectively tuned in magnitude and sign using a phototransistor configuration.
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Affiliation(s)
- Clément Livache
- Sorbonne Université, CNRS , Institut des NanoSciences de Paris, INSP , 75005 Paris , France
- LPEM, ESPCI Paris, PSL Research University, CNRS, Sorbonne Université, 75005 Paris , France
| | - Nicolas Goubet
- Sorbonne Université, CNRS , Institut des NanoSciences de Paris, INSP , 75005 Paris , France
- LPEM, ESPCI Paris, PSL Research University, CNRS, Sorbonne Université, 75005 Paris , France
| | - Bertille Martinez
- Sorbonne Université, CNRS , Institut des NanoSciences de Paris, INSP , 75005 Paris , France
- LPEM, ESPCI Paris, PSL Research University, CNRS, Sorbonne Université, 75005 Paris , France
| | - Amardeep Jagtap
- Sorbonne Université, CNRS , Institut des NanoSciences de Paris, INSP , 75005 Paris , France
| | - Junling Qu
- Sorbonne Université, CNRS , Institut des NanoSciences de Paris, INSP , 75005 Paris , France
| | - Sandrine Ithurria
- LPEM, ESPCI Paris, PSL Research University, CNRS, Sorbonne Université, 75005 Paris , France
| | - Mathieu G Silly
- Synchrotron-SOLEIL , Saint-Aubin BP48 , F91192 Gif sur Yvette Cedex , France
| | - Benoit Dubertret
- LPEM, ESPCI Paris, PSL Research University, CNRS, Sorbonne Université, 75005 Paris , France
| | - Emmanuel Lhuillier
- Sorbonne Université, CNRS , Institut des NanoSciences de Paris, INSP , 75005 Paris , France
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15
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Peyrot D, Silly MG, Silly F. X 3 synthon geometries in two-dimensional halogen-bonded 1,3,5-tris(3,5-dibromophenyl)benzene self-assembled nanoarchitectures on Au(111)-(). Phys Chem Chem Phys 2018; 20:3918-3924. [PMID: 29318234 DOI: 10.1039/c7cp06488h] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The self-assembly of star-shaped 1,3,5-tris(3,5-dibromophenyl)benzene molecules on Au(111)-() in a vacuum is investigated using scanning tunneling microscopy and core-level spectroscopy. Scanning tunneling microscopy shows that the molecules self-assemble into a hexagonal porous halogen-bonded nanoarchitecture. This structure is stabilized by X3-A synthons composed of three type-II halogen-interactions (halogen-bonds). The molecules are oriented along the same direction in this arrangement. Domain boundaries are observed in the hcp region of the herringbone gold surface reconstruction. Molecules of the neighboring domains are rotated by 180°. The domain boundaries are stabilized by the formation of X3-B synthons composed of two type-II and one type-I halogen-interactions between molecules of the neighboring domains. Core-level spectroscopy confirms the existence of two types of halogen-interactions in the organic layer. These observations show that the gold surface reconstructions can be exploited to modify the long-range supramolecular halogen-bonded self-assemblies.
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Affiliation(s)
- David Peyrot
- TITANS, SPEC, CEA, CNRS, Université Paris-Saclay, CEA Saclay, F-91191 Gif sur Yvette, France.
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16
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Gallet JJ, Silly MG, Kazzi ME, Bournel F, Sirotti F, Rochet F. Chemical and kinetic insights into the Thermal Decomposition of an Oxide Layer on Si(111) from Millisecond Photoelectron Spectroscopy. Sci Rep 2017; 7:14257. [PMID: 29079787 PMCID: PMC5660199 DOI: 10.1038/s41598-017-14532-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2017] [Accepted: 10/11/2017] [Indexed: 11/08/2022] Open
Abstract
Despite thermal silicon oxide desorption is a basic operation in semiconductor nanotechnology, its detailed chemical analysis has not been yet realized via time-resolved photoemission. Using an advanced acquisition system and synchrotron radiation, heating schedules with velocities as high as 100 K.s-1 were implemented and highly resolved Si 2p spectra in the tens of millisecond range were obtained. Starting from a Si(111)-7 × 7 surface oxidized in O2 at room temperature (1.4 monolayer of oxygen), changes in the Si 2p spectral shape enabled a detailed chemical analysis of the oxygen redistribution at the surface and of the nucleation, growth and reconstruction of the clean silicon areas. As desorption is an inhomogeneous surface process, the Avrami formalism was adapted to oxide desorption via an original mathematical analysis. The extracted kinetic parameters (the Avrami exponent equal to ~2, the activation energy of ~4.1 eV and a characteristic frequency) were found remarkably stable within a wide (~110 K) desorption temperature window, showing that the Avrami analysis is robust. Both the chemical and kinetic information collected from this experiment can find useful applications when desorption of the oxide layer is a fundamental step in nanofabrication processes on silicon surfaces.
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Affiliation(s)
- J-J Gallet
- Sorbonne Universités, UPMC Univ. Paris 06, and CNRS UMR 7614, Laboratoire de Chimie Physique Matière et Rayonnement (LCPMR), F-75005, Paris, France
- Synchrotron SOLEIL, L'Orme des Merisiers, Saint-Aubin, BP 48, F-91192, Gif-sur-Yvette, France
| | - M G Silly
- Synchrotron SOLEIL, L'Orme des Merisiers, Saint-Aubin, BP 48, F-91192, Gif-sur-Yvette, France
| | - M El Kazzi
- Synchrotron SOLEIL, L'Orme des Merisiers, Saint-Aubin, BP 48, F-91192, Gif-sur-Yvette, France
- Paul Scherrer Institut, 5232, Villigen-PSI, Switzerland
| | - F Bournel
- Sorbonne Universités, UPMC Univ. Paris 06, and CNRS UMR 7614, Laboratoire de Chimie Physique Matière et Rayonnement (LCPMR), F-75005, Paris, France
- Synchrotron SOLEIL, L'Orme des Merisiers, Saint-Aubin, BP 48, F-91192, Gif-sur-Yvette, France
| | - F Sirotti
- Synchrotron SOLEIL, L'Orme des Merisiers, Saint-Aubin, BP 48, F-91192, Gif-sur-Yvette, France
- Laboratoire de Physique de la Matière Condensée, CNRS and Ecole Polytechnique, Université Paris Saclay, F- 91128, Palaiseau, France
| | - F Rochet
- Sorbonne Universités, UPMC Univ. Paris 06, and CNRS UMR 7614, Laboratoire de Chimie Physique Matière et Rayonnement (LCPMR), F-75005, Paris, France.
- Synchrotron SOLEIL, L'Orme des Merisiers, Saint-Aubin, BP 48, F-91192, Gif-sur-Yvette, France.
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17
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Martinez B, Livache C, Notemgnou Mouafo LD, Goubet N, Keuleyan S, Cruguel H, Ithurria S, Aubin H, Ouerghi A, Doudin B, Lacaze E, Dubertret B, Silly MG, Lobo RPSM, Dayen JF, Lhuillier E. HgSe Self-Doped Nanocrystals as a Platform to Investigate the Effects of Vanishing Confinement. ACS Appl Mater Interfaces 2017; 9:36173-36180. [PMID: 28956432 DOI: 10.1021/acsami.7b10665] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Self-doped colloidal quantum dots (CQDs) attract a strong interest for the design of a new generation of low-cost infrared (IR) optoelectronic devices because of their tunable intraband absorption feature in the mid-IR region. However, very little remains known about their electronic structure which combines confinement and an inverted band structure, complicating the design of optimized devices. We use a combination of IR spectroscopy and photoemission to determine the absolute energy levels of HgSe CQDs with various sizes and surface chemistries. We demonstrate that the filling of the CQD states ranges from 2 electrons per CQD at small sizes (<5 nm) to more than 18 electrons per CQD at large sizes (≈20 nm). HgSe CQDs are also an interesting platform to observe vanishing confinement in colloidal nanoparticles. We present lines of evidence for a semiconductor-to-metal transition at the CQD level, through temperature-dependent absorption and transport measurements. In contrast with bulk systems, the transition is the result of the vanishing confinement rather than the increase of the doping level.
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Affiliation(s)
- Bertille Martinez
- Sorbonne Universités, UPMC Univ. Paris 06, CNRS-UMR 7588, Institut des NanoSciences de Paris , 4 Place Jussieu, 75005 Paris, France
- LPEM, ESPCI Paris, PSL Research University , 10 rue Vauquelin, 75005 Paris, France
| | - Clément Livache
- Sorbonne Universités, UPMC Univ. Paris 06, CNRS-UMR 7588, Institut des NanoSciences de Paris , 4 Place Jussieu, 75005 Paris, France
- LPEM, ESPCI Paris, PSL Research University , 10 rue Vauquelin, 75005 Paris, France
| | | | - Nicolas Goubet
- Sorbonne Universités, UPMC Univ. Paris 06, CNRS-UMR 7588, Institut des NanoSciences de Paris , 4 Place Jussieu, 75005 Paris, France
- LPEM, ESPCI Paris, PSL Research University , 10 rue Vauquelin, 75005 Paris, France
| | - Sean Keuleyan
- Voxtel, Inc., University of Oregon, CAMCOR, 1241 University of Oregon , Eugene, Oregon 97403, United States
| | - Hervé Cruguel
- Sorbonne Universités, UPMC Univ. Paris 06, CNRS-UMR 7588, Institut des NanoSciences de Paris , 4 Place Jussieu, 75005 Paris, France
| | - Sandrine Ithurria
- LPEM, ESPCI Paris, PSL Research University , 10 rue Vauquelin, 75005 Paris, France
- Sorbonne Universités, UPMC Univ Paris 06, LPEM , 75005 Paris, France
| | - Hervé Aubin
- LPEM, ESPCI Paris, PSL Research University , 10 rue Vauquelin, 75005 Paris, France
- Sorbonne Universités, UPMC Univ Paris 06, LPEM , 75005 Paris, France
| | - Abdelkarim Ouerghi
- Centre de Nanosciences et de Nanotechnologies, CNRS, Univ. Paris-Sud, Université Paris-Saclay, C2N-Marcoussis , 91460 Marcoussis, France
| | - Bernard Doudin
- Université de Strasbourg, IPCMS-CNRS UMR 7504 , 23 Rue du Loess, 67034 Strasbourg, France
| | - Emmanuelle Lacaze
- Sorbonne Universités, UPMC Univ. Paris 06, CNRS-UMR 7588, Institut des NanoSciences de Paris , 4 Place Jussieu, 75005 Paris, France
| | - Benoit Dubertret
- LPEM, ESPCI Paris, PSL Research University , 10 rue Vauquelin, 75005 Paris, France
- Sorbonne Universités, UPMC Univ Paris 06, LPEM , 75005 Paris, France
| | - Mathieu G Silly
- Synchrotron-SOLEIL , Saint-Aubin, BP48, F91192 Gif sur Yvette Cedex, France
| | - Ricardo P S M Lobo
- LPEM, ESPCI Paris, PSL Research University , 10 rue Vauquelin, 75005 Paris, France
- Sorbonne Universités, UPMC Univ Paris 06, LPEM , 75005 Paris, France
| | - Jean-François Dayen
- Université de Strasbourg, IPCMS-CNRS UMR 7504 , 23 Rue du Loess, 67034 Strasbourg, France
| | - Emmanuel Lhuillier
- Sorbonne Universités, UPMC Univ. Paris 06, CNRS-UMR 7588, Institut des NanoSciences de Paris , 4 Place Jussieu, 75005 Paris, France
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18
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Livache C, Izquierdo E, Martinez B, Dufour M, Pierucci D, Keuleyan S, Cruguel H, Becerra L, Fave JL, Aubin H, Ouerghi A, Lacaze E, Silly MG, Dubertret B, Ithurria S, Lhuillier E. Charge Dynamics and Optolectronic Properties in HgTe Colloidal Quantum Wells. Nano Lett 2017; 17:4067-4074. [PMID: 28598629 DOI: 10.1021/acs.nanolett.7b00683] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
We investigate the electronic and transport properties of HgTe 2D colloidal quantum wells. We demonstrate that the material can be made p- or n-type depending on the capping ligands. In addition to the control of majority carrier type, the surface chemistry also strongly affects the photoconductivity of the material. These transport measurements are correlated with the electronic structure determined by high resolution X-ray photoemission. We attribute the change of majority carriers to the strong hybridization of an n-doped HgS layer resulting from capping the HgTe nanoplatelets by S2- ions. We further investigate the gate and temperature dependence of the photoresponse and its dynamics. We show that the photocurrent rise and fall times can be tuned from 100 μs to 1 ms using the gate bias. Finally, we use time-resolved photoemission spectroscopy as a probe of the transport relaxation to determine if the observed dynamics are limited by a fundamental process such as trapping. These pump probe surface photovoltage measurements show an even faster relaxation in the 100-500 ns range, which suggests that the current performances are rather limited by geometrical factors.
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Affiliation(s)
- Clément Livache
- Institut des NanoSciences de Paris, Sorbonne Universités, UPMC Univ. Paris 06, CNRS-UMR 7588 , 4 place Jussieu, 75005 Paris, France
- Laboratoire de Physique et d'Etude des Matériaux, ESPCI-ParisTech, PSL Research University, Sorbonne Université UPMC Univ. Paris 06, CNRS , 10 rue Vauquelin 75005 Paris, France
| | - Eva Izquierdo
- Laboratoire de Physique et d'Etude des Matériaux, ESPCI-ParisTech, PSL Research University, Sorbonne Université UPMC Univ. Paris 06, CNRS , 10 rue Vauquelin 75005 Paris, France
| | - Bertille Martinez
- Institut des NanoSciences de Paris, Sorbonne Universités, UPMC Univ. Paris 06, CNRS-UMR 7588 , 4 place Jussieu, 75005 Paris, France
| | - Marion Dufour
- Laboratoire de Physique et d'Etude des Matériaux, ESPCI-ParisTech, PSL Research University, Sorbonne Université UPMC Univ. Paris 06, CNRS , 10 rue Vauquelin 75005 Paris, France
| | - Debora Pierucci
- Institut Néel, CNRS-UJF , BP 166, 38042 Grenoble Cedex 9, France
| | - Sean Keuleyan
- Voxtel, Inc., University of Oregon, CAMCOR, 1241 University of Oregon , Eugene, Oregon 97403, United States
| | - Hervé Cruguel
- Institut des NanoSciences de Paris, Sorbonne Universités, UPMC Univ. Paris 06, CNRS-UMR 7588 , 4 place Jussieu, 75005 Paris, France
| | - Loic Becerra
- Institut des NanoSciences de Paris, Sorbonne Universités, UPMC Univ. Paris 06, CNRS-UMR 7588 , 4 place Jussieu, 75005 Paris, France
| | - Jean Louis Fave
- Institut des NanoSciences de Paris, Sorbonne Universités, UPMC Univ. Paris 06, CNRS-UMR 7588 , 4 place Jussieu, 75005 Paris, France
| | - Hervé Aubin
- Laboratoire de Physique et d'Etude des Matériaux, ESPCI-ParisTech, PSL Research University, Sorbonne Université UPMC Univ. Paris 06, CNRS , 10 rue Vauquelin 75005 Paris, France
| | - Abdelkarim Ouerghi
- Laboratoire de Photonique et de Nanostructures (CNRS-LPN), Route de Nozay, 91460 Marcoussis, France
| | - Emmanuelle Lacaze
- Institut des NanoSciences de Paris, Sorbonne Universités, UPMC Univ. Paris 06, CNRS-UMR 7588 , 4 place Jussieu, 75005 Paris, France
| | - Mathieu G Silly
- Synchrotron-SOLEIL, Saint-Aubin, BP48, F91192 Gif sur Yvette Cedex, France
| | - Benoit Dubertret
- Laboratoire de Physique et d'Etude des Matériaux, ESPCI-ParisTech, PSL Research University, Sorbonne Université UPMC Univ. Paris 06, CNRS , 10 rue Vauquelin 75005 Paris, France
| | - Sandrine Ithurria
- Laboratoire de Physique et d'Etude des Matériaux, ESPCI-ParisTech, PSL Research University, Sorbonne Université UPMC Univ. Paris 06, CNRS , 10 rue Vauquelin 75005 Paris, France
| | - Emmanuel Lhuillier
- Institut des NanoSciences de Paris, Sorbonne Universités, UPMC Univ. Paris 06, CNRS-UMR 7588 , 4 place Jussieu, 75005 Paris, France
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19
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Silly MG, Ferté T, Tordeux MA, Pierucci D, Beaulieu N, Chauvet C, Pressacco F, Sirotti F, Popescu H, Lopez-Flores V, Tortarolo M, Sacchi M, Jaouen N, Hollander P, Ricaud JP, Bergeard N, Boeglin C, Tudu B, Delaunay R, Luning J, Malinowski G, Hehn M, Baumier C, Fortuna F, Krizmancic D, Stebel L, Sergo R, Cautero G. Pump-probe experiments at the TEMPO beamline using the low-α operation mode of Synchrotron SOLEIL. J Synchrotron Radiat 2017; 24:886-897. [PMID: 28664896 DOI: 10.1107/s1600577517007913] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2017] [Accepted: 05/28/2017] [Indexed: 06/07/2023]
Abstract
The SOLEIL synchrotron radiation source is regularly operated in special filling modes dedicated to pump-probe experiments. Among others, the low-α mode operation is characterized by shorter pulse duration and represents the natural bridge between 50 ps synchrotron pulses and femtosecond experiments. Here, the capabilities in low-α mode of the experimental set-ups developed at the TEMPO beamline to perform pump-probe experiments with soft X-rays based on photoelectron or photon detection are presented. A 282 kHz repetition-rate femtosecond laser is synchronized with the synchrotron radiation time structure to induce fast electronic and/or magnetic excitations. Detection is performed using a two-dimensional space resolution plus time resolution detector based on microchannel plates equipped with a delay line. Results of time-resolved photoelectron spectroscopy, circular dichroism and magnetic scattering experiments are reported, and their respective advantages and limitations in the framework of high-time-resolution pump-probe experiments compared and discussed.
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Affiliation(s)
- Mathieu G Silly
- Synchrotron SOLEIL, L'Orme des Merisiers, Saint Aubin, Gif sur Yvette 91192, France
| | - Tom Ferté
- Université de Strasbourg, CNRS, Institut de Physique et Chimie des Matériaux de Strasbourg, UMR 7504, F-67000 Strasbourg, France
| | - Marie Agnes Tordeux
- Synchrotron SOLEIL, L'Orme des Merisiers, Saint Aubin, Gif sur Yvette 91192, France
| | - Debora Pierucci
- Synchrotron SOLEIL, L'Orme des Merisiers, Saint Aubin, Gif sur Yvette 91192, France
| | - Nathan Beaulieu
- Synchrotron SOLEIL, L'Orme des Merisiers, Saint Aubin, Gif sur Yvette 91192, France
| | - Christian Chauvet
- Synchrotron SOLEIL, L'Orme des Merisiers, Saint Aubin, Gif sur Yvette 91192, France
| | - Federico Pressacco
- Synchrotron SOLEIL, L'Orme des Merisiers, Saint Aubin, Gif sur Yvette 91192, France
| | - Fausto Sirotti
- Synchrotron SOLEIL, L'Orme des Merisiers, Saint Aubin, Gif sur Yvette 91192, France
| | - Horia Popescu
- Synchrotron SOLEIL, L'Orme des Merisiers, Saint Aubin, Gif sur Yvette 91192, France
| | - Victor Lopez-Flores
- Synchrotron SOLEIL, L'Orme des Merisiers, Saint Aubin, Gif sur Yvette 91192, France
| | - Marina Tortarolo
- Synchrotron SOLEIL, L'Orme des Merisiers, Saint Aubin, Gif sur Yvette 91192, France
| | - Maurizio Sacchi
- Synchrotron SOLEIL, L'Orme des Merisiers, Saint Aubin, Gif sur Yvette 91192, France
| | - Nicolas Jaouen
- Synchrotron SOLEIL, L'Orme des Merisiers, Saint Aubin, Gif sur Yvette 91192, France
| | - Philippe Hollander
- Synchrotron SOLEIL, L'Orme des Merisiers, Saint Aubin, Gif sur Yvette 91192, France
| | - Jean Paul Ricaud
- Synchrotron SOLEIL, L'Orme des Merisiers, Saint Aubin, Gif sur Yvette 91192, France
| | - Nicolas Bergeard
- Université de Strasbourg, CNRS, Institut de Physique et Chimie des Matériaux de Strasbourg, UMR 7504, F-67000 Strasbourg, France
| | - Christine Boeglin
- Université de Strasbourg, CNRS, Institut de Physique et Chimie des Matériaux de Strasbourg, UMR 7504, F-67000 Strasbourg, France
| | - Bharati Tudu
- Sorbonne Universités, UPMC Université Paris VI, CNRS, Laboratoire de Chimie Physique - Matière et Rayonnement, Paris 75005, France
| | - Renaud Delaunay
- Sorbonne Universités, UPMC Université Paris VI, CNRS, Laboratoire de Chimie Physique - Matière et Rayonnement, Paris 75005, France
| | - Jan Luning
- Synchrotron SOLEIL, L'Orme des Merisiers, Saint Aubin, Gif sur Yvette 91192, France
| | - Gregory Malinowski
- P2M - Institut Jean Lamour UMR7198, CNRS - Université de Lorraine, Vandoeuvre-les-Nancy 54506, France
| | - Michel Hehn
- P2M - Institut Jean Lamour UMR7198, CNRS - Université de Lorraine, Vandoeuvre-les-Nancy 54506, France
| | - Cédric Baumier
- CSNSM, Université Paris Sud and CNRS/IN2P3, Batiment 104 et 108, Orsay 91405, France
| | - Franck Fortuna
- CSNSM, Université Paris Sud and CNRS/IN2P3, Batiment 104 et 108, Orsay 91405, France
| | - Damjan Krizmancic
- Laboratorio TASC, IOM-CNR, SS 14 Km 163.5, Basovizza, I-34149 Trieste, Italy
| | - Luigi Stebel
- ELETTRA Sincrotrone Trieste SCpA, Area Science Park, Strada Statale 14 Km 163.5, I-34012 Basovizza, Italy
| | - Rudi Sergo
- ELETTRA Sincrotrone Trieste SCpA, Area Science Park, Strada Statale 14 Km 163.5, I-34012 Basovizza, Italy
| | - Giuseppe Cautero
- ELETTRA Sincrotrone Trieste SCpA, Area Science Park, Strada Statale 14 Km 163.5, I-34012 Basovizza, Italy
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20
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Clark PCJ, Radtke H, Pengpad A, Williamson AI, Spencer BF, Hardman SJO, Leontiadou MA, Neo DCJ, Fairclough SM, Watt AAR, Pis I, Nappini S, Bondino F, Magnano E, Handrup K, Schulte K, Silly MG, Sirotti F, Flavell WR. The passivating effect of cadmium in PbS/CdS colloidal quantum dots probed by nm-scale depth profiling. Nanoscale 2017; 9:6056-6067. [PMID: 28443889 DOI: 10.1039/c7nr00672a] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Achieving control of the surface chemistry of colloidal quantum dots (CQDs) is essential to fully exploit their properties in solar cells, but direct measurement of the chemistry and electronic structure in the outermost atomic layers is challenging. Here we probe the surface oxidation and passivation of cation-exchanged PbS/CdS core/shell CQDs with sub nm-scale precision using synchrotron-radiation-excited depth-profiling photoemission. We investigate the surface composition of the topmost 1-2.5 nm of the CQDs as a function of depth, for CQDs of varying CdS shell thickness, and examine how the surface changes after prolonged air exposure. We demonstrate that the Cd is localized at the surface of the CQDs. The surface-localized products of oxidation are identified, and the extent of oxidation quantified. We show that oxidised sulfur species are progressively eliminated as Cd replaces Pb at the surface. A sub-monolayer surface 'decoration' of Cd is found to be effective in passivating the CQDs. We show that the measured energy-level alignments at PbS/CdS colloidal quantum dot surfaces differ from those expected on the basis of bulk band offsets, and are strongly affected by the oxidation products. We develop a model for the passivating action of Cd. The optimum shell thickness (of around 0.1 nm, previously found to give maximised power conversion efficiency in PbS/CdS solar cells) is found to correspond to a trade-off between the rate of oxidation and the introduction of a surface barrier to charge transport.
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Affiliation(s)
- Pip C J Clark
- School of Physics and Astronomy and the Photon Science Institute, The University of Manchester, Manchester M13 9PL, UK.
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21
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Pierucci D, Henck H, Ben Aziza Z, Naylor CH, Balan A, Rault JE, Silly MG, Dappe YJ, Bertran F, Le Fèvre P, Sirotti F, Johnson ATC, Ouerghi A. Tunable Doping in Hydrogenated Single Layered Molybdenum Disulfide. ACS Nano 2017; 11:1755-1761. [PMID: 28146631 DOI: 10.1021/acsnano.6b07661] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Structural defects in the molybdenum disulfide (MoS2) monolayer are widely known for strongly altering its properties. Therefore, a deep understanding of these structural defects and how they affect MoS2 electronic properties is of fundamental importance. Here, we report on the incorporation of atomic hydrogen in monolayered MoS2 to tune its structural defects. We demonstrate that the electronic properties of single layer MoS2 can be tuned from the intrinsic electron (n) to hole (p) doping via controlled exposure to atomic hydrogen at room temperature. Moreover, this hydrogenation process represents a viable technique to completely saturate the sulfur vacancies present in the MoS2 flakes. The successful incorporation of hydrogen in MoS2 leads to the modification of the electronic properties as evidenced by high resolution X-ray photoemission spectroscopy and density functional theory calculations. Micro-Raman spectroscopy and angle resolved photoemission spectroscopy measurements show the high quality of the hydrogenated MoS2 confirming the efficiency of our hydrogenation process. These results demonstrate that the MoS2 hydrogenation could be a significant and efficient way to achieve tunable doping of transition metal dichalcogenides (TMD) materials with non-TMD elements.
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Affiliation(s)
- Debora Pierucci
- Centre de Nanosciences et de Nanotechnologies, CNRS, Univ. Paris-Sud, Université Paris-Saclay , C2N - Marcoussis, F91460 Marcoussis, France
| | - Hugo Henck
- Centre de Nanosciences et de Nanotechnologies, CNRS, Univ. Paris-Sud, Université Paris-Saclay , C2N - Marcoussis, F91460 Marcoussis, France
| | - Zeineb Ben Aziza
- Centre de Nanosciences et de Nanotechnologies, CNRS, Univ. Paris-Sud, Université Paris-Saclay , C2N - Marcoussis, F91460 Marcoussis, France
| | - Carl H Naylor
- Department of Physics and Astronomy, University of Pennsylvania , 209S 33rd Street, Philadelphia, Pennsylvania 19104, United States
| | - Adrian Balan
- Department of Physics and Astronomy, University of Pennsylvania , 209S 33rd Street, Philadelphia, Pennsylvania 19104, United States
| | - Julien E Rault
- Synchrotron-SOLEIL , Saint-Aubin, BP48, F91192 Gif sur Yvette Cedex, France
| | - Mathieu G Silly
- Synchrotron-SOLEIL , Saint-Aubin, BP48, F91192 Gif sur Yvette Cedex, France
| | - Yannick J Dappe
- SPEC, CEA, CNRS, Université Paris-Saclay , CEA Saclay, F91191 Gif-sur-Yvette Cedex, France
| | - François Bertran
- Synchrotron-SOLEIL , Saint-Aubin, BP48, F91192 Gif sur Yvette Cedex, France
| | - Patrick Le Fèvre
- Synchrotron-SOLEIL , Saint-Aubin, BP48, F91192 Gif sur Yvette Cedex, France
| | - Fausto Sirotti
- Synchrotron-SOLEIL , Saint-Aubin, BP48, F91192 Gif sur Yvette Cedex, France
| | - A T Charlie Johnson
- Department of Physics and Astronomy, University of Pennsylvania , 209S 33rd Street, Philadelphia, Pennsylvania 19104, United States
| | - Abdelkarim Ouerghi
- Centre de Nanosciences et de Nanotechnologies, CNRS, Univ. Paris-Sud, Université Paris-Saclay , C2N - Marcoussis, F91460 Marcoussis, France
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22
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Ben Aziza Z, Henck H, Pierucci D, Silly MG, Lhuillier E, Patriarche G, Sirotti F, Eddrief M, Ouerghi A. van der Waals Epitaxy of GaSe/Graphene Heterostructure: Electronic and Interfacial Properties. ACS Nano 2016; 10:9679-9686. [PMID: 27715006 DOI: 10.1021/acsnano.6b05521] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
Stacking two-dimensional materials in so-called van der Waals (vdW) heterostructures, like the combination of GaSe and graphene, provides the ability to obtain hybrid systems that are suitable to design optoelectronic devices. Here, we report the structural and electronic properties of the direct growth of multilayered GaSe by molecular beam epitaxy on graphene. Reflection high-energy electron diffraction images exhibited sharp streaky features indicative of a high-quality GaSe layer produced via a vdW epitaxy. Micro-Raman spectroscopy showed that, after the vdW heterointerface formation, the Raman signature of pristine graphene is preserved. However, the GaSe film tuned the charge density of graphene layer by shifting the Dirac point by about 80 meV toward lower binding energies, attesting to an electron transfer from graphene to GaSe. Angle-resolved photoemission spectroscopy (ARPES) measurements showed that the maximum of the valence band of the few layers of GaSe are located at the Γ point at a binding energy of about -0.73 eV relative to the Fermi level (p-type doping). From the ARPES measurements, a hole effective mass defined along the ΓM direction and equal to about m*/m0 = -1.1 was determined. By coupling the ARPES data with high-resolution X-ray photoemission spectroscopy measurements, the Schottky interface barrier height was estimated to be 1.2 eV. These findings allow a deeper understanding of the interlayer interactions and the electronic structure of the GaSe/graphene vdW heterostructure.
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Affiliation(s)
- Zeineb Ben Aziza
- Centre de Nanosciences et de Nanotechnologies, CNRS, Université Paris-Sud, Université Paris-Saclay , C2N-Marcoussis, 91460 Marcoussis, France
| | - Hugo Henck
- Centre de Nanosciences et de Nanotechnologies, CNRS, Université Paris-Sud, Université Paris-Saclay , C2N-Marcoussis, 91460 Marcoussis, France
| | - Debora Pierucci
- Centre de Nanosciences et de Nanotechnologies, CNRS, Université Paris-Sud, Université Paris-Saclay , C2N-Marcoussis, 91460 Marcoussis, France
| | - Mathieu G Silly
- Synchrotron-SOLEIL , Saint-Aubin, BP48, F91192 Gif sur Yvette Cedex, France
| | - Emmanuel Lhuillier
- Sorbonne Universités, UPMC Université Paris 06, UMR 7588, INSP , F-75005 Paris, France
- CNRS, UMR 7588, Institut des NanoSciences de Paris (INSP) , F-75005 Paris, France
| | - Gilles Patriarche
- Centre de Nanosciences et de Nanotechnologies, CNRS, Université Paris-Sud, Université Paris-Saclay , C2N-Marcoussis, 91460 Marcoussis, France
| | - Fausto Sirotti
- Synchrotron-SOLEIL , Saint-Aubin, BP48, F91192 Gif sur Yvette Cedex, France
| | - Mahmoud Eddrief
- Sorbonne Universités, UPMC Université Paris 06, UMR 7588, INSP , F-75005 Paris, France
- CNRS, UMR 7588, Institut des NanoSciences de Paris (INSP) , F-75005 Paris, France
| | - Abdelkarim Ouerghi
- Centre de Nanosciences et de Nanotechnologies, CNRS, Université Paris-Sud, Université Paris-Saclay , C2N-Marcoussis, 91460 Marcoussis, France
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23
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Pierucci D, Brumme T, Girard JC, Calandra M, Silly MG, Sirotti F, Barbier A, Mauri F, Ouerghi A. Atomic and electronic structure of trilayer graphene/SiC(0001): Evidence of Strong Dependence on Stacking Sequence and charge transfer. Sci Rep 2016; 6:33487. [PMID: 27629702 PMCID: PMC5024167 DOI: 10.1038/srep33487] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2016] [Accepted: 08/24/2016] [Indexed: 11/28/2022] Open
Abstract
The transport properties of few-layer graphene are the directly result of a peculiar band structure near the Dirac point. Here, for epitaxial graphene grown on SiC, we determine the effect of charge transfer from the SiC substrate on the local density of states (LDOS) of trilayer graphene using scaning tunneling microscopy/spectroscopy and angle resolved photoemission spectroscopy (ARPES). Different spectra are observed and are attributed to the existence of two stable polytypes of trilayer: Bernal (ABA) and rhomboedreal (ABC) staking. Their electronic properties strongly depend on the charge transfer from the substrate. We show that the LDOS of ABC stacking shows an additional peak located above the Dirac point in comparison with the LDOS of ABA stacking. The observed LDOS features, reflecting the underlying symmetry of the two polytypes, were reproduced by explicit calculations within density functional theory (DFT) including the charge transfer from the substrate. These findings demonstrate the pronounced effect of stacking order and charge transfer on the electronic structure of trilayer or few layer graphene. Our approach represents a significant step toward understand the electronic properties of graphene layer under electrical field.
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Affiliation(s)
- Debora Pierucci
- Centre de Nanosciences et de Nanotechnologies, CNRS, Univ. Paris-Sud, Université Paris-Saclay, C2N–Marcoussis, 91460 Marcoussis, France
| | - Thomas Brumme
- Institut de Minéralogie, de Physique des Matériaux, et de Cosmochimie, UMR CNRS 7590, Sorbonne Universités, UPMC, Univ. Paris VI, MNHN, IRD, 4 Place Jussieu, 75005 Paris, France
- Max Planck Institute for the Structure and Dynamics of Matter, Luruper Chaussee 149, 22761 Hamburg, Germany
| | - Jean-Christophe Girard
- Centre de Nanosciences et de Nanotechnologies, CNRS, Univ. Paris-Sud, Université Paris-Saclay, C2N–Marcoussis, 91460 Marcoussis, France
| | - Matteo Calandra
- Institut de Minéralogie, de Physique des Matériaux, et de Cosmochimie, UMR CNRS 7590, Sorbonne Universités, UPMC, Univ. Paris VI, MNHN, IRD, 4 Place Jussieu, 75005 Paris, France
| | - Mathieu G. Silly
- Synchrotron-SOLEIL, Saint-Aubin, BP48, F91192 Gif sur Yvette Cedex, France
| | - Fausto Sirotti
- Synchrotron-SOLEIL, Saint-Aubin, BP48, F91192 Gif sur Yvette Cedex, France
| | - Antoine Barbier
- Service de Physique de l’Etat Condensé, DSM/IRAMIS/SPEC, CEA-CNRS UMR 3680, CEA-Saclay, F-91191 Gif-sur-Yvette, France
| | - Francesco Mauri
- Departimento di Fisica, Università di Roma La Sapienza, Piazzale Aldo Moro 5, I-00185 Roma, Italy
- Graphene Labs, Fondazione Istituto Italiano di Tecnologia, Via Morego, I-16163 Genova, Italy
| | - Abdelkarim Ouerghi
- Centre de Nanosciences et de Nanotechnologies, CNRS, Univ. Paris-Sud, Université Paris-Saclay, C2N–Marcoussis, 91460 Marcoussis, France
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24
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Pierucci D, Henck H, Avila J, Balan A, Naylor CH, Patriarche G, Dappe YJ, Silly MG, Sirotti F, Johnson ATC, Asensio MC, Ouerghi A. Band Alignment and Minigaps in Monolayer MoS2-Graphene van der Waals Heterostructures. Nano Lett 2016; 16:4054-4061. [PMID: 27281693 DOI: 10.1021/acs.nanolett.6b00609] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Two-dimensional layered MoS2 shows great potential for nanoelectronic and optoelectronic devices due to its high photosensitivity, which is the result of its indirect to direct band gap transition when the bulk dimension is reduced to a single monolayer. Here, we present an exhaustive study of the band alignment and relativistic properties of a van der Waals heterostructure formed between single layers of MoS2 and graphene. A sharp, high-quality MoS2-graphene interface was obtained and characterized by micro-Raman spectroscopy, high-resolution X-ray photoemission spectroscopy (HRXPS), and scanning high-resolution transmission electron microscopy (STEM/HRTEM). Moreover, direct band structure determination of the MoS2/graphene van der Waals heterostructure monolayer was carried out using angle-resolved photoemission spectroscopy (ARPES), shedding light on essential features such as doping, Fermi velocity, hybridization, and band-offset of the low energy electronic dynamics found at the interface. We show that, close to the Fermi level, graphene exhibits a robust, almost perfect, gapless, and n-doped Dirac cone and no significant charge transfer doping is detected from MoS2 to graphene. However, modification of the graphene band structure occurs at rather larger binding energies, as the opening of several miniband-gaps is observed. These miniband-gaps resulting from the overlay of MoS2 and the graphene layer lattice impose a superperiodic potential.
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Affiliation(s)
- Debora Pierucci
- Centre de Nanosciences et de Nanotechnologies, CNRS Univ. Paris-Sud, Université Paris-Saclay , C2N - Marcoussis, 91460 Marcoussis, France
| | - Hugo Henck
- Centre de Nanosciences et de Nanotechnologies, CNRS Univ. Paris-Sud, Université Paris-Saclay , C2N - Marcoussis, 91460 Marcoussis, France
| | - Jose Avila
- Synchrotron-SOLEIL , Saint-Aubin, BP48, F91192 Gif sur Yvette Cedex, France
| | - Adrian Balan
- Department of Physics and Astronomy, University of Pennsylvania , 209S 33rd Street, Philadelphia, Pennsylvania 19104 6396, United States
- LICSEN, NIMBE, CEA, CNRS, Université Paris Saclay , CEA Saclay, 91191 Gif-sur-Yvette, France
| | - Carl H Naylor
- Department of Physics and Astronomy, University of Pennsylvania , 209S 33rd Street, Philadelphia, Pennsylvania 19104 6396, United States
| | - Gilles Patriarche
- Centre de Nanosciences et de Nanotechnologies, CNRS Univ. Paris-Sud, Université Paris-Saclay , C2N - Marcoussis, 91460 Marcoussis, France
| | - Yannick J Dappe
- SPEC, CEA, CNRS, Université Paris Saclay , CEA Saclay, 91191 Gif-sur-Yvette Cedex, France
| | - Mathieu G Silly
- Synchrotron-SOLEIL , Saint-Aubin, BP48, F91192 Gif sur Yvette Cedex, France
| | - Fausto Sirotti
- Synchrotron-SOLEIL , Saint-Aubin, BP48, F91192 Gif sur Yvette Cedex, France
| | - A T Charlie Johnson
- Department of Physics and Astronomy, University of Pennsylvania , 209S 33rd Street, Philadelphia, Pennsylvania 19104 6396, United States
| | - Maria C Asensio
- Synchrotron-SOLEIL , Saint-Aubin, BP48, F91192 Gif sur Yvette Cedex, France
| | - Abdelkarim Ouerghi
- Centre de Nanosciences et de Nanotechnologies, CNRS Univ. Paris-Sud, Université Paris-Saclay , C2N - Marcoussis, 91460 Marcoussis, France
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25
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Guan X, Becdelievre J, Meunier B, Benali A, Saint-Girons G, Bachelet R, Regreny P, Botella C, Grenet G, Blanchard NP, Jaurand X, Silly MG, Sirotti F, Chauvin N, Gendry M, Penuelas J. GaAs Core/SrTiO3 Shell Nanowires Grown by Molecular Beam Epitaxy. Nano Lett 2016; 16:2393-2399. [PMID: 27008537 DOI: 10.1021/acs.nanolett.5b05182] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
We have studied the growth of a SrTiO3 shell on self-catalyzed GaAs nanowires grown by vapor-liquid-solid assisted molecular beam epitaxy on Si(111) substrates. To control the growth of the SrTiO3 shell, the GaAs nanowires were protected using an arsenic capping/decapping procedure in order to prevent uncontrolled oxidation and/or contamination of the nanowire facets. Reflection high energy electron diffraction, scanning electron microscopy, transmission electron microscopy, and X-ray photoelectron spectroscopy were performed to determine the structural, chemical, and morphological properties of the heterostructured nanowires. Using adapted oxide growth conditions, it is shown that most of the perovskite structure SrTiO3 shell appears to be oriented with respect to the GaAs lattice. These results are promising for achieving one-dimensional epitaxial semiconductor core/functional oxide shell nanostructures.
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Affiliation(s)
- X Guan
- Institut des Nanotechnologies de Lyon, Université de Lyon, UMR 5270-CNRS, Ecole Centrale de Lyon , 36 avenue Guy de Collongue, F-69134 Ecully Cedex, France
| | - J Becdelievre
- Institut des Nanotechnologies de Lyon, Université de Lyon, UMR 5270-CNRS, Ecole Centrale de Lyon , 36 avenue Guy de Collongue, F-69134 Ecully Cedex, France
| | - B Meunier
- Institut des Nanotechnologies de Lyon, Université de Lyon, UMR 5270-CNRS, Ecole Centrale de Lyon , 36 avenue Guy de Collongue, F-69134 Ecully Cedex, France
| | - A Benali
- Institut des Nanotechnologies de Lyon, Université de Lyon, UMR 5270-CNRS, Ecole Centrale de Lyon , 36 avenue Guy de Collongue, F-69134 Ecully Cedex, France
| | - G Saint-Girons
- Institut des Nanotechnologies de Lyon, Université de Lyon, UMR 5270-CNRS, Ecole Centrale de Lyon , 36 avenue Guy de Collongue, F-69134 Ecully Cedex, France
| | - R Bachelet
- Institut des Nanotechnologies de Lyon, Université de Lyon, UMR 5270-CNRS, Ecole Centrale de Lyon , 36 avenue Guy de Collongue, F-69134 Ecully Cedex, France
| | - P Regreny
- Institut des Nanotechnologies de Lyon, Université de Lyon, UMR 5270-CNRS, Ecole Centrale de Lyon , 36 avenue Guy de Collongue, F-69134 Ecully Cedex, France
| | - C Botella
- Institut des Nanotechnologies de Lyon, Université de Lyon, UMR 5270-CNRS, Ecole Centrale de Lyon , 36 avenue Guy de Collongue, F-69134 Ecully Cedex, France
| | - G Grenet
- Institut des Nanotechnologies de Lyon, Université de Lyon, UMR 5270-CNRS, Ecole Centrale de Lyon , 36 avenue Guy de Collongue, F-69134 Ecully Cedex, France
| | - N P Blanchard
- Institut Lumière Matière (ILM), UMR5306 Université Lyon 1-CNRS Université de Lyon , 69622 Villeurbanne Cedex, France
| | - X Jaurand
- Centre Technologique des Microstructures, Université Claude Bernard Lyon 1 , 5 rue Raphael Dubois-Bâtiment Darwin B, F-69622, Villeurbanne Cedex, France
| | - M G Silly
- Synchrotron SOLEIL (TEMPO Beamline), l'Orme des Merisiers, Saint-Aubin, 91192 Gif-sur-Yvette, France
| | - F Sirotti
- Synchrotron SOLEIL (TEMPO Beamline), l'Orme des Merisiers, Saint-Aubin, 91192 Gif-sur-Yvette, France
| | - N Chauvin
- Institut des Nanotechnologies de Lyon, Université de Lyon, UMR 5270-CNRS, INSA-Lyon , 7 avenue Jean Capelle, 69621 Villeurbanne, France
| | - M Gendry
- Institut des Nanotechnologies de Lyon, Université de Lyon, UMR 5270-CNRS, Ecole Centrale de Lyon , 36 avenue Guy de Collongue, F-69134 Ecully Cedex, France
| | - J Penuelas
- Institut des Nanotechnologies de Lyon, Université de Lyon, UMR 5270-CNRS, Ecole Centrale de Lyon , 36 avenue Guy de Collongue, F-69134 Ecully Cedex, France
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26
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Hajlaoui M, Sediri H, Pierucci D, Henck H, Phuphachong T, Silly MG, de Vaulchier LA, Sirotti F, Guldner Y, Belkhou R, Ouerghi A. High Electron Mobility in Epitaxial Trilayer Graphene on Off-axis SiC(0001). Sci Rep 2016; 6:18791. [PMID: 26739366 PMCID: PMC4704025 DOI: 10.1038/srep18791] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2015] [Accepted: 11/09/2015] [Indexed: 11/09/2022] Open
Abstract
The van de Waals heterostructure formed by an epitaxial trilayer graphene is of particular interest due to its unique tunable electronic band structure and stacking sequence. However, to date, there has been a lack in the fundamental understanding of the electronic properties of epitaxial trilayer graphene. Here, we investigate the electronic properties of large-area epitaxial trilayer graphene on a 4° off-axis SiC(0001) substrate. Micro-Raman mappings and atomic force microscopy (AFM) confirmed predominantly trilayer on the sample obtained under optimized conditions. We used angle-resolved photoemission spectroscopy (ARPES) and Density Functional Theory (DFT) calculations to study in detail the structure of valence electronic states, in particular the dispersion of π bands in reciprocal space and the exact determination of the number of graphene layers. Using far-infrared magneto-transmission (FIR-MT), we demonstrate, that the electron cyclotron resonance (CR) occurs between Landau levels with a (B)(1/2) dependence. The CR line-width is consistent with a high Dirac fermions mobility of ~3000 cm(2)·V(-1)·s(-1) at 4 K.
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Affiliation(s)
- Mahdi Hajlaoui
- CNRS- Laboratoire de Photonique et de Nanostructures, Route de Nozay, 91460 Marcoussis, France.,Synchrotron-SOLEIL, Saint-Aubin, BP48, F91192 Gif sur Yvette Cedex, France
| | - Haikel Sediri
- CNRS- Laboratoire de Photonique et de Nanostructures, Route de Nozay, 91460 Marcoussis, France
| | - Debora Pierucci
- CNRS- Laboratoire de Photonique et de Nanostructures, Route de Nozay, 91460 Marcoussis, France
| | - Hugo Henck
- CNRS- Laboratoire de Photonique et de Nanostructures, Route de Nozay, 91460 Marcoussis, France
| | - Thanyanan Phuphachong
- Laboratoire Pierre Aigrain, Ecole Normale Supérieure-PSL Research University, CNRS, Université Pierre &Marie Curie-Sorbonne Universités, 24 rue Lhomond, 75005 Paris, France
| | - Mathieu G Silly
- Synchrotron-SOLEIL, Saint-Aubin, BP48, F91192 Gif sur Yvette Cedex, France
| | - Louis-Anne de Vaulchier
- Laboratoire Pierre Aigrain, Ecole Normale Supérieure-PSL Research University, CNRS, Université Pierre &Marie Curie-Sorbonne Universités, 24 rue Lhomond, 75005 Paris, France
| | - Fausto Sirotti
- Synchrotron-SOLEIL, Saint-Aubin, BP48, F91192 Gif sur Yvette Cedex, France
| | - Yves Guldner
- Laboratoire Pierre Aigrain, Ecole Normale Supérieure-PSL Research University, CNRS, Université Pierre &Marie Curie-Sorbonne Universités, 24 rue Lhomond, 75005 Paris, France
| | - Rachid Belkhou
- Synchrotron-SOLEIL, Saint-Aubin, BP48, F91192 Gif sur Yvette Cedex, France
| | - Abdelkarim Ouerghi
- CNRS- Laboratoire de Photonique et de Nanostructures, Route de Nozay, 91460 Marcoussis, France
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Tissot H, Gallet JJ, Bournel F, Olivieri G, Silly MG, Sirotti F, Boucly A, Rochet F. The Electronic Structure of Saturated NaCl and NaI Solutions in Contact with a Gold Substrate. Top Catal 2015. [DOI: 10.1007/s11244-015-0530-6] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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28
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Sediri H, Pierucci D, Hajlaoui M, Henck H, Patriarche G, Dappe YJ, Yuan S, Toury B, Belkhou R, Silly MG, Sirotti F, Boutchich M, Ouerghi A. Atomically Sharp Interface in an h-BN-epitaxial graphene van der Waals Heterostructure. Sci Rep 2015; 5:16465. [PMID: 26585245 PMCID: PMC4653732 DOI: 10.1038/srep16465] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2015] [Accepted: 10/05/2015] [Indexed: 11/24/2022] Open
Abstract
Stacking various two-dimensional atomic crystals is a feasible approach to creating unique multilayered van der Waals heterostructures with tailored properties. Herein for the first time, we present a controlled preparation of large-area h-BN/graphene heterostructures via a simple chemical deposition of h-BN layers on epitaxial graphene/SiC(0001). Van der Waals forces, which are responsible for the cohesion of the multilayer system, give rise to an abrupt interface without interdiffusion between graphene and h-BN, as shown by X-ray Photoemission Spectroscopy (XPS) and direct observation using scanning and High-Resolution Transmission Electron Microscopy (STEM/HRTEM). The electronic properties of graphene, such as the Dirac cone, remain intact and no significant charge transfer i.e. doping, is observed. These results are supported by Density Functional Theory (DFT) calculations. We demonstrate that the h-BN capped graphene allows the fabrication of vdW heterostructures without altering the electronic properties of graphene.
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Affiliation(s)
- Haikel Sediri
- Laboratoire de Photonique et de Nanostructures (LPN), CNRS, Université Paris-Saclay, route de Nozay, F-91460 Marcoussis, France
| | - Debora Pierucci
- Laboratoire de Photonique et de Nanostructures (LPN), CNRS, Université Paris-Saclay, route de Nozay, F-91460 Marcoussis, France
| | - Mahdi Hajlaoui
- Laboratoire de Photonique et de Nanostructures (LPN), CNRS, Université Paris-Saclay, route de Nozay, F-91460 Marcoussis, France.,Synchrotron-SOLEIL, Saint-Aubin, BP48, F91192 Gif sur Yvette Cedex, France
| | - Hugo Henck
- Laboratoire de Photonique et de Nanostructures (LPN), CNRS, Université Paris-Saclay, route de Nozay, F-91460 Marcoussis, France
| | - Gilles Patriarche
- Laboratoire de Photonique et de Nanostructures (LPN), CNRS, Université Paris-Saclay, route de Nozay, F-91460 Marcoussis, France
| | - Yannick J Dappe
- SPEC, CEA, CNRS, Université Paris Saclay, CEA Saclay, 91191, Gif-Sur-Yvette, France
| | - Sheng Yuan
- Laboratoire des Multimatériaux et Interfaces, UMR CNRS 5615, Université Lyon I, Université de Lyon, France
| | - Bérangère Toury
- Laboratoire des Multimatériaux et Interfaces, UMR CNRS 5615, Université Lyon I, Université de Lyon, France
| | - Rachid Belkhou
- Synchrotron-SOLEIL, Saint-Aubin, BP48, F91192 Gif sur Yvette Cedex, France
| | - Mathieu G Silly
- Synchrotron-SOLEIL, Saint-Aubin, BP48, F91192 Gif sur Yvette Cedex, France
| | - Fausto Sirotti
- Synchrotron-SOLEIL, Saint-Aubin, BP48, F91192 Gif sur Yvette Cedex, France
| | - Mohamed Boutchich
- GeePs, CNRS UMR8507, CentraleSupelec, Univ Paris-Sud, Sorbonne Universités-UPMC Univ Paris 06, 11 rue Joliot-Curie, Plateau de Moulon, 91192 Gif-sur-Yvette Cedex, France
| | - Abdelkarim Ouerghi
- Laboratoire de Photonique et de Nanostructures (LPN), CNRS, Université Paris-Saclay, route de Nozay, F-91460 Marcoussis, France
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29
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Pierucci D, Sediri H, Hajlaoui M, Girard JC, Brumme T, Calandra M, Velez-Fort E, Patriarche G, Silly MG, Ferro G, Soulière V, Marangolo M, Sirotti F, Mauri F, Ouerghi A. Evidence for Flat Bands near the Fermi Level in Epitaxial Rhombohedral Multilayer Graphene. ACS Nano 2015; 9:5432-9. [PMID: 25893537 DOI: 10.1021/acsnano.5b01239] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
The stacking order of multilayer graphene has a profound influence on its electronic properties. In particular, it has been predicted that a rhombohedral stacking sequence displays a very flat conducting surface state: the longer the sequence, the flatter the band. In such a flat band, the role of electron-electron correlation is enhanced, possibly resulting in high Tc superconductivity, magnetic order, or charge density wave order. Here we demonstrate that rhombohedral multilayers are easily obtained by epitaxial growth on 3C-SiC(111) on a 2° off-axis 6H-SiC(0001). The resulting samples contain rhombohedral sequences of five layers on 70% of the surface. We confirm the presence of the flat band at the Fermi level by scanning tunneling spectroscopy and angle-resolved photoemission spectroscopy, in close agreement with the predictions of density functional theory calculations.
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Affiliation(s)
- Debora Pierucci
- †Laboratoire de Photonique et de Nanostructures (CNRS-LPN), Route de Nozay, 91460 Marcoussis, France
| | - Haikel Sediri
- †Laboratoire de Photonique et de Nanostructures (CNRS-LPN), Route de Nozay, 91460 Marcoussis, France
| | - Mahdi Hajlaoui
- †Laboratoire de Photonique et de Nanostructures (CNRS-LPN), Route de Nozay, 91460 Marcoussis, France
- ‡Synchrotron-SOLEIL, Saint-Aubin, BP48, F91192 Cedex Gif sur Yvette, France
| | - Jean-Christophe Girard
- †Laboratoire de Photonique et de Nanostructures (CNRS-LPN), Route de Nozay, 91460 Marcoussis, France
| | - Thomas Brumme
- §Institut de Minéralogie, de Physique des Matériaux, et de Cosmochimie, UMR CNRS 7590, Sorbonne Universités, UPMC, Univ. Paris VI, MNHN, IRD, 4 place Jussieu, 75005 Paris, France
| | - Matteo Calandra
- §Institut de Minéralogie, de Physique des Matériaux, et de Cosmochimie, UMR CNRS 7590, Sorbonne Universités, UPMC, Univ. Paris VI, MNHN, IRD, 4 place Jussieu, 75005 Paris, France
| | - Emilio Velez-Fort
- †Laboratoire de Photonique et de Nanostructures (CNRS-LPN), Route de Nozay, 91460 Marcoussis, France
- §Institut de Minéralogie, de Physique des Matériaux, et de Cosmochimie, UMR CNRS 7590, Sorbonne Universités, UPMC, Univ. Paris VI, MNHN, IRD, 4 place Jussieu, 75005 Paris, France
| | - Gilles Patriarche
- †Laboratoire de Photonique et de Nanostructures (CNRS-LPN), Route de Nozay, 91460 Marcoussis, France
| | - Mathieu G Silly
- ‡Synchrotron-SOLEIL, Saint-Aubin, BP48, F91192 Cedex Gif sur Yvette, France
| | - Gabriel Ferro
- ∥Laboratoire des multimateriaux et Interfaces, UMR 5615, Université Claude Bernard Lyon I, 69100 Villeurbanne, France
| | - Véronique Soulière
- ∥Laboratoire des multimateriaux et Interfaces, UMR 5615, Université Claude Bernard Lyon I, 69100 Villeurbanne, France
| | - Massimiliano Marangolo
- ⊥UMR 7588, INSP, Sorbonne Universités, UPMC Univ Paris 06, 4 place Jussieu, F-75005 Paris, France
- #CNRS, UMR 7588, Institut des Nanosciences de Paris, 4 place Jussieu, F-75005 Paris, France
| | - Fausto Sirotti
- ‡Synchrotron-SOLEIL, Saint-Aubin, BP48, F91192 Cedex Gif sur Yvette, France
| | - Francesco Mauri
- §Institut de Minéralogie, de Physique des Matériaux, et de Cosmochimie, UMR CNRS 7590, Sorbonne Universités, UPMC, Univ. Paris VI, MNHN, IRD, 4 place Jussieu, 75005 Paris, France
| | - Abdelkarim Ouerghi
- †Laboratoire de Photonique et de Nanostructures (CNRS-LPN), Route de Nozay, 91460 Marcoussis, France
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30
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Gogneau N, Ben Gouider Trabelsi A, Silly MG, Ridene M, Portail M, Michon A, Oueslati M, Belkhou R, Sirotti F, Ouerghi A. Investigation of structural and electronic properties of epitaxial graphene on 3C-SiC(100)/Si(100) substrates. Nanotechnol Sci Appl 2014; 7:85-95. [PMID: 25339846 PMCID: PMC4203311 DOI: 10.2147/nsa.s60324] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Graphene has been intensively studied in recent years in order to take advantage of its unique properties. Its synthesis on SiC substrates by solid-state graphitization appears a suitable option for graphene-based electronics. However, before developing devices based on epitaxial graphene, it is desirable to understand and finely control the synthesis of material with the most promising properties. To achieve these prerequisites, many studies are being conducted on various SiC substrates. Here, we review 3C-SiC(100) epilayers grown by chemical vapor deposition on Si(100) substrates for producing graphene by solid state graphitization under ultrahigh-vacuum conditions. Based on various characterization techniques, the structural and electrical properties of epitaxial graphene layer grown on 3C-SiC(100)/Si(100) are discussed. We establish that epitaxial graphene presents properties similar to those obtained using hexagonal SiC substrates, with the advantage of being compatible with current Si-processing technology.
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Affiliation(s)
- Noelle Gogneau
- Laboratoire de Photonique et de Nanostructures, Centre National de la Recherche Scientifique, Marcoussis, France
| | - Amira Ben Gouider Trabelsi
- Unité des Nanomatériaux et Photonique, Faculté des Sciences de Tunis, Université de Tunis El Manar Campus Universitaire, Tunis, Tunisia
| | - Mathieu G Silly
- Synchrotron-SOLEIL, Saint-Aubin, BP48, F91192 Gif sur Yvette Cedex, France
| | - Mohamed Ridene
- Laboratoire de Photonique et de Nanostructures, Centre National de la Recherche Scientifique, Marcoussis, France
| | - Marc Portail
- Centre de Recherche sur l’HétéroEpitaxie et Ses Application, Centre National de la Recherche Scientifique, Valbonne, France
| | - Adrien Michon
- Centre de Recherche sur l’HétéroEpitaxie et Ses Application, Centre National de la Recherche Scientifique, Valbonne, France
| | - Mehrezi Oueslati
- Unité des Nanomatériaux et Photonique, Faculté des Sciences de Tunis, Université de Tunis El Manar Campus Universitaire, Tunis, Tunisia
| | - Rachid Belkhou
- Synchrotron-SOLEIL, Saint-Aubin, BP48, F91192 Gif sur Yvette Cedex, France
| | - Fausto Sirotti
- Synchrotron-SOLEIL, Saint-Aubin, BP48, F91192 Gif sur Yvette Cedex, France
| | - Abdelkarim Ouerghi
- Laboratoire de Photonique et de Nanostructures, Centre National de la Recherche Scientifique, Marcoussis, France
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31
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Spencer BF, Cliffe MJ, Graham DM, Hardman SJO, Seddon EA, Syres KL, Thomas AG, Sirotti F, Silly MG, Akhtar J, O'Brien P, Fairclough SM, Smith JM, Chattopadhyay S, Flavell WR. Dynamics in next-generation solar cells: time-resolved surface photovoltage measurements of quantum dots chemically linked to ZnO (101̄0). Faraday Discuss 2014; 171:275-98. [DOI: 10.1039/c4fd00019f] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
The charge dynamics at the surface of the transparent conducting oxide and photoanode material ZnO are investigated in the presence and absence of light-harvesting colloidal quantum dots (QDs). The time-resolved change in surface potential upon photoexcitation has been measured in the m-plane ZnO (101̄0) using a laser pump-synchrotron X-ray probe methodology. By varying the oxygen annealing conditions, and hence the oxygen vacancy concentration of the sample, we find that dark carrier lifetimes at the ZnO surface vary from hundreds of μs to ms timescales, i.e. a persistent photoconductivity (PPC) is observed. The highly-controlled nature of our experiments under ultra-high vacuum (UHV), and the use of band-gap and sub-band-gap photoexcitation, allow us to demonstrate that defect states ca. 340 meV above the valence band edge are directly associated with the PPC, and that the PPC mediated by these defects dominates over the oxygen photodesorption mechanism. These observations are consistent with the hypothesis that ionized oxygen vacancy states are responsible for the PPC in ZnO. The effect of chemically linking two colloidal QD systems (type I PbS and type II CdS–ZnSe) to the surface has also been investigated. Upon deposition of the QDs onto the surface, the dark carrier lifetime and the surface photovoltage are reduced, suggesting a direct injection of charge carriers into the ZnO conduction band. The results are discussed in the context of the development of next-generation solar cells.
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Affiliation(s)
- Ben F. Spencer
- School of Physics and Astronomy and the Photon Science Institute
- The University of Manchester
- , United Kingdom
- The Cockcroft Institute
- Sci-Tech Daresbury, Keckwick Lane, Daresbury
| | - Matthew J. Cliffe
- School of Physics and Astronomy and the Photon Science Institute
- The University of Manchester
- , United Kingdom
- The Cockcroft Institute
- Sci-Tech Daresbury, Keckwick Lane, Daresbury
| | - Darren M. Graham
- School of Physics and Astronomy and the Photon Science Institute
- The University of Manchester
- , United Kingdom
| | - Samantha J. O. Hardman
- Manchester Institute of Biotechnology
- Faculty of Life Sciences
- University of Manchester
- Manchester M1 7DN, United Kingdom
| | - Elaine A. Seddon
- School of Physics and Astronomy and the Photon Science Institute
- The University of Manchester
- , United Kingdom
- The Cockcroft Institute
- Sci-Tech Daresbury, Keckwick Lane, Daresbury
| | - Karen L. Syres
- School of Chemistry
- The University of Nottingham
- Nottingham NG7 2RD, United Kingdom
| | - Andrew G. Thomas
- School of Physics and Astronomy and the Photon Science Institute
- The University of Manchester
- , United Kingdom
| | | | | | - Javeed Akhtar
- Department of Chemistry
- University of Manchester
- Manchester M13 9PL, United Kingdom
- Department of Physics
- Nano-Science & Materials Synthesis Laboratory
| | - Paul O'Brien
- Department of Chemistry
- University of Manchester
- Manchester M13 9PL, United Kingdom
| | | | - Jason M. Smith
- Department of Materials
- University of Oxford
- Oxford OX1 3PH, United Kingdom
| | - Swapan Chattopadhyay
- The Cockcroft Institute
- Sci-Tech Daresbury, Keckwick Lane, Daresbury
- Warrington WA4 4AD, United Kingdom
| | - Wendy R. Flavell
- School of Physics and Astronomy and the Photon Science Institute
- The University of Manchester
- , United Kingdom
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Tchalala MR, Ali MA, Enriquez H, Kara A, Lachgar A, Yagoubi S, Foy E, Vega E, Bendounan A, Silly MG, Sirotti F, Nitshe S, Chaudanson D, Jamgotchian H, Aufray B, Mayne AJ, Dujardin G, Oughaddou H. Silicon sheets by redox assisted chemical exfoliation. J Phys Condens Matter 2013; 25:442001. [PMID: 24131870 DOI: 10.1088/0953-8984/25/44/442001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
In this paper, we report the direct chemical synthesis of silicon sheets in gram-scale quantities by chemical exfoliation of pre-processed calcium disilicide (CaSi2). We have used a combination of x-ray photoelectron spectroscopy, transmission electron microscopy and energy-dispersive x-ray spectroscopy to characterize the obtained silicon sheets. We found that the clean and crystalline silicon sheets show a two-dimensional hexagonal graphitic structure.
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33
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Velez-Fort E, Mathieu C, Pallecchi E, Pigneur M, Silly MG, Belkhou R, Marangolo M, Shukla A, Sirotti F, Ouerghi A. Epitaxial graphene on 4H-SiC(0001) grown under nitrogen flux: evidence of low nitrogen doping and high charge transfer. ACS Nano 2012; 6:10893-10900. [PMID: 23148722 DOI: 10.1021/nn304315z] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Nitrogen doping of graphene is of great interest for both fundamental research to explore the effect of dopants on a 2D electrical conductor and applications such as lithium storage, composites, and nanoelectronic devices. Here, we report on the modifications of the electronic properties of epitaxial graphene thanks to the introduction, during the growth, of nitrogen-atom substitution in the carbon honeycomb lattice. High-resolution transmission microscopy and low-energy electron microscopy investigations indicate that the nitrogen-doped graphene is uniform at large scale. The substitution of nitrogen atoms in the graphene planes was confirmed by high-resolution X-ray photoelectron spectroscopy, which reveals several atomic configurations for the nitrogen atoms: graphitic-like, pyridine-like, and pyrrolic-like. Angle-resolved photoemission measurements show that the N-doped graphene exhibits large n-type carrier concentrations of 2.6 × 10(13) cm(-2), about 4 times more than what is found for pristine graphene, grown under similar pressure conditions. Our experiments demonstrate that a small amount of dopants (<1%) can significantly tune the electronic properties of graphene by shifting the Dirac cone about 0.3 eV toward higher binding energies with respect to the π band of pristine graphene, which is a key feature for envisioning applications in nanoelectronics.
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Affiliation(s)
- Emilio Velez-Fort
- Laboratoire de Photonique et de Nanostructures (CNRS-LPN), Route de Nozay, 91460 Marcoussis, France
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Ouerghi A, Silly MG, Marangolo M, Mathieu C, Eddrief M, Picher M, Sirotti F, El Moussaoui S, Belkhou R. Large-area and high-quality epitaxial graphene on off-axis SiC wafers. ACS Nano 2012; 6:6075-6082. [PMID: 22702396 DOI: 10.1021/nn301152p] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
The growth of large and uniform graphene layers remains very challenging to this day due to the close correlation between the electronic and transport properties and the layer morphology. Here, we report the synthesis of uniform large-scale mono- and bilayers of graphene on off-axis 6H-SiC(0001) substrates. The originality of our approach consists of the fine control of the growth mode of the graphene by precise control of the Si sublimation rate. Moreover, we take advantage of the presence of nanofacets on the off-axis substrate to grow a large and uniform graphene with good long-range order. We believe that our approach represents a significant step toward the scalable synthesis of graphene films with high structural qualities and fine thickness control, in order to develop graphene-based electronic devices.
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Affiliation(s)
- Abdelkarim Ouerghi
- Laboratoire de Photonique et de Nanostructures, CNRS-LPN, Route de Nozay, 91460 Marcoussis, France.
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35
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D'Angelo M, Yukawa R, Ozawa K, Yamamoto S, Hirahara T, Hasegawa S, Silly MG, Sirotti F, Matsuda I. Hydrogen-induced surface metallization of SrTiO3(001). Phys Rev Lett 2012; 108:116802. [PMID: 22540498 DOI: 10.1103/physrevlett.108.116802] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2011] [Indexed: 05/31/2023]
Abstract
Surface metallization of SrTiO3(001) by hydrogen adsorption is experimentally confirmed for the first time by photoemission spectroscopy and surface conductivity measurements. The metallic state is assigned to a quantized state in the space-charge layer induced by electron doping from hydrogen atoms. The measured two-dimensional (2D) conductivity is well above the 2D Ioffe-Regel limit indicating that the system is in a metallic conduction regime. The mean free path of the surface electron is estimated to be several nanometers at room temperature.
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Affiliation(s)
- M D'Angelo
- Institut des Nanosciences de Paris, Université Pierre et Marie Curie-Paris 6, CNRS-UMR 7588, Paris, France.
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Guzzo M, Lani G, Sottile F, Romaniello P, Gatti M, Kas JJ, Rehr JJ, Silly MG, Sirotti F, Reining L. Valence electron photoemission spectrum of semiconductors: ab initio description of multiple satellites. Phys Rev Lett 2011; 107:166401. [PMID: 22107408 DOI: 10.1103/physrevlett.107.166401] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2011] [Indexed: 05/31/2023]
Abstract
The experimental valence band photoemission spectrum of semiconductors exhibits multiple satellites that cannot be described by the GW approximation for the self-energy in the framework of many-body perturbation theory. Taking silicon as a prototypical example, we compare experimental high energy photoemission spectra with GW calculations and analyze the origin of the GW failure. We then propose an approximation to the functional differential equation that determines the exact one-body Green's function, whose solution has an exponential form. This yields a calculated spectrum, including cross sections, secondary electrons, and an estimate for extrinsic and interference effects, in excellent agreement with experiment. Our result can be recast as a dynamical vertex correction beyond GW, giving hints for further developments.
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Affiliation(s)
- Matteo Guzzo
- Laboratoire des Solides Irradiés, École Polytechnique, CNRS, CEA-DSM, F-91128 Palaiseau, France.
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37
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Chauvet C, Polack F, Silly MG, Lagarde B, Thomasset M, Kubsky S, Duval JP, Risterucci P, Pilette B, Yao I, Bergeard N, Sirotti F. Carbon contamination of soft X-ray beamlines: dramatic anti-reflection coating effects observed in the 1 keV photon energy region. J Synchrotron Radiat 2011; 18:761-764. [PMID: 21862857 DOI: 10.1107/s0909049511023119] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2011] [Accepted: 06/14/2011] [Indexed: 05/31/2023]
Abstract
Carbon contamination is a general problem of under-vacuum optics submitted to high fluence. In soft X-ray beamlines carbon deposit on optics is known to absorb and scatter radiation close to the C K-edge (280 eV), forbidding effective measurements in this spectral region. Here the observation of strong reflectivity losses is reported related to carbon deposition at much higher energies around 1000 eV, where carbon absorptivity is small. It is shown that the observed effect can be modelled as a destructive interference from a homogeneous carbon thin film.
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Affiliation(s)
- C Chauvet
- Synchrotron Soleil, L'Orme des Merisiers, Saint Aubin, Gif sur Yvette, France
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38
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Bergeard N, Silly MG, Krizmancic D, Chauvet C, Guzzo M, Ricaud JP, Izquierdo M, Stebel L, Pittana P, Sergo R, Cautero G, Dufour G, Rochet F, Sirotti F. Time-resolved photoelectron spectroscopy using synchrotron radiation time structure. J Synchrotron Radiat 2011; 18:245-250. [PMID: 21335912 DOI: 10.1107/s0909049510052301] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2010] [Accepted: 12/13/2010] [Indexed: 05/30/2023]
Abstract
Synchrotron radiation time structure is becoming a common tool for studying dynamic properties of materials. The main limitation is often the wide time domain the user would like to access with pump-probe experiments. In order to perform photoelectron spectroscopy experiments over time scales from milliseconds to picoseconds it is mandatory to measure the time at which each measured photoelectron was created. For this reason the usual CCD camera-based two-dimensional detection of electron energy analyzers has been replaced by a new delay-line detector adapted to the time structure of the SOLEIL synchrotron radiation source. The new two-dimensional delay-line detector has a time resolution of 5 ns and was installed on a Scienta SES 2002 electron energy analyzer. The first application has been to characterize the time of flight of the photoemitted electrons as a function of their kinetic energy and the selected pass energy. By repeating the experiment as a function of the available pass energy and of the kinetic energy, a complete characterization of the analyzer behaviour in the time domain has been obtained. Even for kinetic energies as low as 10 eV at 2 eV pass energy, the time spread of the detected electrons is lower than 140 ns. These results and the time structure of the SOLEIL filling modes assure the possibility of performing pump-probe photoelectron spectroscopy experiments with the time resolution given by the SOLEIL pulse width, the best performance of the beamline and of the experimental station.
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Affiliation(s)
- N Bergeard
- Synchrotron-SOLEIL, BP 48, Saint-Aubin, F91192 Gif sur Yvette Cedex, France
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Hardman SJO, Graham DM, Stubbs SK, Spencer BF, Seddon EA, Fung HT, Gardonio S, Sirotti F, Silly MG, Akhtar J, O'Brien P, Binks DJ, Flavell WR. Electronic and surface properties of PbS nanoparticles exhibiting efficient multiple exciton generation. Phys Chem Chem Phys 2011; 13:20275-83. [DOI: 10.1039/c1cp22330e] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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Huang K, Demadrille R, Silly MG, Sirotti F, Reiss P, Renault O. Internal structure of InP/ZnS nanocrystals unraveled by high-resolution soft X-ray photoelectron spectroscopy. ACS Nano 2010; 4:4799-805. [PMID: 20666468 DOI: 10.1021/nn100581t] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
High-energy resolution photoelectron spectroscopy (DeltaE < 200 meV) is used to investigate the internal structure of semiconductor quantum dots containing low Z-contrast elements. In InP/ZnS core/shell nanocrystals synthesized using a single-step procedure (core and shell precursors added at the same time), a homogeneously alloyed InPZnS core structure is evidenced by quantitative analysis of their In3d(5/2) spectra recorded at variable excitation energy. When using a two-step method (core InP nanocrystal synthesis followed by subsequent ZnS shell growth), XPS analysis reveals a graded core/shell interface. We demonstrate the existence of In-S and S(x)-In-P(1-x) bonding states in both types of InP/ZnS nanocrystals, which allows a refined view on the underlying reaction mechanisms.
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Affiliation(s)
- Kai Huang
- CEA Grenoble, INAC/SPrAM, UMR 5819 CEA-CNRS-UJF/LEMOH, 17 rue des Martyrs, 38054 Grenoble Cedex 9, France
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41
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Silly MG, Porrès L, Mongin O, Chollet PA, Blanchard-Desce M. Optical limiting in the red–NIR range with soluble two-photon absorbing molecules. Chem Phys Lett 2003. [DOI: 10.1016/j.cplett.2003.08.017] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Derycke V, Soukiassian PG, Amy F, Chabal YJ, D'angelo MD, Enriquez HB, Silly MG. Nanochemistry at the atomic scale revealed in hydrogen-induced semiconductor surface metallization. Nat Mater 2003; 2:253-258. [PMID: 12690399 DOI: 10.1038/nmat835] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/28/2002] [Accepted: 01/17/2003] [Indexed: 05/24/2023]
Abstract
Passivation of semiconductor surfaces against chemical attack can be achieved by terminating the surface-dangling bonds with a monovalent atom such as hydrogen. Such passivation invariably leads to the removal of all surface states in the bandgap, and thus to the termination of non-metallic surfaces. Here we report the first observation of semiconductor surface metallization induced by atomic hydrogen. This result, established by using photo-electron and photo-absorption spectroscopies and scanning tunnelling techniques, is achieved on a Si-terminated cubic silicon carbide (SiC) surface. It results from competition between hydrogen termination of surface-dangling bonds and hydrogen-generated steric hindrance below the surface. Understanding the ingredient for hydrogen-stabilized metallization directly impacts the ability to eliminate electronic defects at semiconductor interfaces critical for microelectronics, provides a means to develop electrical contacts on high-bandgap chemically passive materials, particularly for interfacing with biological systems, and gives control of surfaces for lubrication, for example of nanomechanical devices.
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Affiliation(s)
- Vincent Derycke
- Commissariat à l'Energie Atomique, Laboratoire Surfaces et Interfaces de Matériaux Avancés associé à l'Université de Paris-Sud/Orsay, DSM-DRECAM-SPCSI, Bâtiment 462, Saclay, 91191 Gif sur Yvette Cedex, France
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