1601
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Lee SW, Liu Y, Heo J, Gordon RG. Creation and control of two-dimensional electron gas using Al-based amorphous oxides/SrTiO₃ heterostructures grown by atomic layer deposition. NANO LETTERS 2012; 12:4775-4783. [PMID: 22908907 DOI: 10.1021/nl302214x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
The formation of a two-dimensional electron gas (2-DEG) using SrTiO(3) (STO)-based heterostructures provides promising opportunities in oxide electronics. We realized the formation of 2-DEG using several amorphous layers grown by the atomic layer deposition (ALD) technique at 300 °C which is a process compatible with mass production and thereby can provide the realization of potential applications. We found that the amorphous LaAlO(3) (LAO) layer grown by the ALD process can generate 2-DEG (∼1 × 10(13)/cm(2)) with an electron mobility of 4-5 cm(2)/V·s. A much higher electron mobility was observed at lower temperatures. More remarkably, amorphous YAlO(3) (YAO) and Al(2)O(3) layers, which are not polar-perovskite-structured oxides, can create 2-DEG as well. 2-DEG was created by means of the important role of trimethylaluminum, Me(3)Al, as a reducing agent for STO during LAO and YAO ALD as well as the Al(2)O(3) ALD process at 300 °C. The deposited oxide layer also plays an essential role as a catalyst that enables Me(3)Al to reduce the STO. The electrons were localized very near to the STO surface, and the source of carriers was explained based on the oxygen vacancies generated in the STO substrate.
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Affiliation(s)
- Sang Woon Lee
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, United States
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1602
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Li F, Yao X, Wang Z, Xing W, Jin W, Huang J, Wang Y. Highly porous metal oxide networks of interconnected nanotubes by atomic layer deposition. NANO LETTERS 2012; 12:5033-5038. [PMID: 22888959 DOI: 10.1021/nl3028312] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Mesoporous metal oxide networks composed of interconnected nanotubes with ultrathin tube walls down to 3 nm and high porosity up to 90% were fabricated by atomic layer deposition (ALD) of alumina or titania onto templates of swelling-induced porous block copolymers. The nanotube networks possessed dual sets of interconnected pores separated by the tube wall whose thickness could be finely tuned by altering ALD cycles. Because of the excellent pore interconnectivity and high porosity, the alumina nanotube networks showed superior humidity-sensing performances.
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Affiliation(s)
- Fengbin Li
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemistry and Chemical Engineering, Nanjing University of Technology, Nanjing 210009, Jiangsu, People's Republic of China
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1603
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Sun H, Qin X, Zaera F. Activation of Metal-Organic Precursors by Electron Bombardment in the Gas Phase for Enhanced Deposition of Solid Films. J Phys Chem Lett 2012; 3:2523-2527. [PMID: 26292144 DOI: 10.1021/jz3011332] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The incorporation of gas-phase electron-impact ionization and activation of metal-organic compounds into atomic layer deposition (ALD) processes is reported as a way to enhance film growth with stable precursors. Specifically, it is shown here that gas-phase activation of methylcyclopentadienylmanganese tricarbonyl, MeCpMn(CO)3, which was accomplished by using a typical nude ion gauge employed in many ultrahigh-vacuum (UHV) studies, enhances its dissociative adsorption on silicon surfaces, affording the design of ALD cycles with more extensive Mn deposition and at lower temperatures. Significantly higher Mn uptakes were demonstrated by X-ray photoelectron spectroscopy (XPS) on both silicon dioxide films and on Si(100) wafers Ar(+)-sputtered to remove their native oxide layer. The effectiveness of this electron-impact activation approach in ALD is explained in terms of the cracking patterns seen in mass spectrometry for the metal-organic precursor used.
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Affiliation(s)
- Huaxing Sun
- Department of Chemistry, University of California, Riverside, California 92521, United States
| | - Xiangdong Qin
- Department of Chemistry, University of California, Riverside, California 92521, United States
| | - Francisco Zaera
- Department of Chemistry, University of California, Riverside, California 92521, United States
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1604
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Riha SC, Libera JA, Elam JW, Martinson ABF. Design and implementation of an integral wall-mounted quartz crystal microbalance for atomic layer deposition. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2012; 83:094101. [PMID: 23020393 DOI: 10.1063/1.4753935] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Quartz crystal microbalance (QCM) measurements have played a vital role in understanding and expediting new atomic layer deposition (ALD) processes; however, significant barriers remain to their routine use and accurate execution. In order to turn this exclusively in situ technique into a routine characterization method, an integral QCM fixture was developed. This new design is easily implemented on a variety of chemical vapor deposition (CVD) tools, allows rapid sample exchange, prevents backside deposition, and minimizes both the footprint and flow disturbance. Unlike previous QCM designs, the fast thermal equilibration enables tasks such as temperature-dependent studies and ex situ sample exchange, further highlighting the utility of this QCM design for day-to-day use. Finally, the in situ mapping of thin film growth rates across the ALD reactor was demonstrated in a popular commercial tool operating in both continuous and quasi-static ALD modes.
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Affiliation(s)
- Shannon C Riha
- Materials Science Division, Argonne National Laboratory, 9700 S. Cass Avenue, Argonne, Illinois 60439, USA
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1605
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Ishchuk S, Taffa DH, Hazut O, Kaynan N, Yerushalmi R. Transformation of organic-inorganic hybrid films obtained by molecular layer deposition to photocatalytic layers with enhanced activity. ACS NANO 2012; 6:7263-9. [PMID: 22768917 DOI: 10.1021/nn302370y] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
We present the transformation of organic-inorganic hybrid titanicone films formed by TiCl(4) as metal precursor and ethylene glycol (EG) using solvent-free MLD to highly active photocatalytic films. The photocatalytic activities of the films were investigated using hydroxyl-functionalized porphyrin as a spectroscopic marker. TEM imaging and electron diffraction, XPS, UV-vis spectroscopy, and spectroscsopic ellipsometry were employed for structural and composition analyses of the films. The photocatalytic activity of Ti-EG films was investigated for different anneal temperatures and compared to TiO(2) films prepared by ALD using TiCl(4) as metal precursor and H(2)O (TiO(2) films). Overall, our results indicate that the photocatalytic activity of the thermally annealed Ti-EG film is about 5-fold increased compared to that of the TiO(2) film prepared by ALD for optimal process conditions. The combined results indicate that the structural and photocatalytic properties can be assigned to three states: (I) amorphous state, intermediate dye loading, low photocatalytic activity, (II) intermediate film state with both crystalline and amorphous regions, high dye loading, high catalytic activity, and (III) highly crystalline film with low dye loading and low photocatalytic activity. The formation of photocatalytic nanotubes (NTs) is demonstrated using sacrificial Ge nanowires (NWs) scaffolds to yield Ti-EG NT structures with controllable wall thickness structures and enhanced dye loading capacity. Our results demonstrate the feasibility and high potential of MLD to form metal oxides with high photocatalytic activity.
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Affiliation(s)
- Sergey Ishchuk
- Institute of Chemistry and the Center for Nanoscience and Nanotechnology, The Hebrew University of Jerusalem, Edmond J Safra Campus, Givat Ram Jerusalem, 91904, Israel
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1606
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Warburton WK, Hennig W, Bertrand JA, George SM, Biegalski S. Atomic layer deposition α-Al2O3 diffusion barriers to eliminate the memory effect in beta-gamma radioxenon detectors. J Radioanal Nucl Chem 2012. [DOI: 10.1007/s10967-012-2061-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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1607
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1608
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Malm J, Sajavaara T, Karppinen M. Atomic Layer Deposition of WO3 Thin Films using W(CO)6 and O3 Precursors. ACTA ACUST UNITED AC 2012. [DOI: 10.1002/cvde.201206986] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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1609
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Chandiran AK, Tetreault N, Humphry-Baker R, Kessler F, Baranoff E, Yi C, Nazeeruddin MK, Grätzel M. Subnanometer Ga2O3 tunnelling layer by atomic layer deposition to achieve 1.1 V open-circuit potential in dye-sensitized solar cells. NANO LETTERS 2012; 12:3941-7. [PMID: 22681486 DOI: 10.1021/nl301023r] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Herein, we present the first use of a gallium oxide tunnelling layer to significantly reduce electron recombination in dye-sensitized solar cells (DSC). The subnanometer coating is achieved using atomic layer deposition (ALD) and leading to a new DSC record open-circuit potential of 1.1 V with state-of-the-art organic D-π-A sensitizer and cobalt redox mediator. After ALD of only a few angstroms of Ga(2)O(3), the electron back reaction is reduced by more than an order of magnitude, while charge collection efficiency and fill factor are increased by 30% and 15%, respectively. The photogenerated exciton separation processes of electron injection into the TiO(2) conduction band and the hole injection into the electrolyte are characterized in detail.
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Affiliation(s)
- Aravind Kumar Chandiran
- Laboratory of Photonics and Interfaces, Institute of Chemical Sciences and Engineering, Swiss Federal Institute of Technology (EPFL) , Station 6, 1015 Lausanne, Switzerland.
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1610
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Mackus AJM, Dielissen SAF, Mulders JJL, Kessels WMM. Nanopatterning by direct-write atomic layer deposition. NANOSCALE 2012; 4:4477-4480. [PMID: 22760689 DOI: 10.1039/c2nr30664f] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
A novel direct-write approach is presented, which relies on area-selective atomic layer deposition on seed layer patterns deposited by electron beam induced deposition. The method enables the nanopatterning of high-quality material with a lateral resolution of only ∼10 nm. Direct-write ALD is a viable alternative to lithography-based patterning with a better compatibility with sensitive nanomaterials.
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Affiliation(s)
- A J M Mackus
- Department of Applied Physics, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands.
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1611
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Yang Z, Gao S, Li T, Liu FQ, Ren Y, Xu T. Enhanced electron extraction from template-free 3D nanoparticulate transparent conducting oxide (TCO) electrodes for dye-sensitized solar cells. ACS APPLIED MATERIALS & INTERFACES 2012; 4:4419-4427. [PMID: 22834639 DOI: 10.1021/am301090a] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
The semiconducting metal oxide-based photoanodes in the most efficient dye-sensitized solar cells (DSSCs) desires a low doping level to promote charge separation, which, however, limits the subsequent electron extraction in the slow diffusion regime. These conflicts are mitigated in a new photoanode design that decouples the charge separation and extraction functions. A three-dimensional highly doped fluorinated SnO(2) (FTO) nanoparticulate film serves as conductive core for low-resistance and drift-assisted charge extraction while a thin, low-doped conformal TiO(2) shell maintains a large resistance to recombination (and therefore long charge lifetime). EIS reveals that the electron transit time is reduced by orders of magnitude, whereas the recombination resistance remains in the range of traditional nanoparticle TiO(2) photoelectrodes.
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Affiliation(s)
- Zhenzhen Yang
- Department of Chemistry and Biochemistry, Northern Illinois University, Dekalb, Illinois 60115, United States
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1612
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Peng Q, Efimenko K, Genzer J, Parsons GN. Oligomer orientation in vapor-molecular-layer-deposited alkyl-aromatic polyamide films. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2012; 28:10464-70. [PMID: 22765908 DOI: 10.1021/la3017936] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
The surface-limited molecular-layer deposition of alkyl-aromatic polyamide films using sequential doses of 1,4-butane diamine (BDA) and terephthaloyl dichloride (TDC) is characterized using in situ quartz crystal microbalance and ex situ spectroscopy analysis. For the first time, near-edge X-ray absorption fine structure (NEXAFS) spectroscopy is used to offer insight into molecular orientation in films deposited via molecular-layer deposition (MLD). The results show that the oligomer units are lying nearly parallel to the surface, which differs from the linear vertical growth mode often used to illustrate film growth.
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Affiliation(s)
- Qing Peng
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, North Carolina 27695, United States.
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1613
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Meng X, Yang XQ, Sun X. Emerging applications of atomic layer deposition for lithium-ion battery studies. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2012; 24:3589-3615. [PMID: 22700328 DOI: 10.1002/adma.201200397] [Citation(s) in RCA: 212] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2012] [Revised: 03/22/2012] [Indexed: 06/01/2023]
Abstract
Lithium-ion batteries (LIBs) are used widely in today's consumer electronics and offer great potential for hybrid electric vehicles (HEVs), plug-in HEVs, pure EVs, and also in smart grids as future energy-storage devices. However, many challenges must be addressed before these future applications of LIBs are realized, such as the energy and power density of LIBs, their cycle and calendar life, safety characteristics, and costs. Recently, a technique called atomic layer deposition (ALD) attracted great interest as a novel tool and approach for resolving these issues. In this article, recent advances in using ALD for LIB studies are thoroughly reviewed, covering two technical routes: 1) ALD for designing and synthesizing new LIB components, i.e., anodes, cathodes, and solid electrolytes, and; 2) ALD used in modifying electrode properties via surface coating. This review will hopefully stimulate more extensive and insightful studies on using ALD for developing high-performance LIBs.
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Affiliation(s)
- Xiangbo Meng
- Department of Mechanical and Materials Engineering, The University of Western Ontario, London, ON N6A 5B8, Canada
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1614
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Johns JE, Karmel HJ, Alaboson JMP, Hersam MC. Probing the Structure and Chemistry of Perylenetetracarboxylic Dianhydride on Graphene Before and After Atomic Layer Deposition of Alumina. J Phys Chem Lett 2012; 3:1974-1979. [PMID: 22905282 PMCID: PMC3419543 DOI: 10.1021/jz300802k] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
The superlative electronic properties of graphene suggest its use as the foundation of next generation integrated circuits. However, this application requires precise control of the interface between graphene and other materials, especially the metal oxides that are commonly used as gate dielectrics. Towards that end, organic seeding layers have been empirically shown to seed ultrathin dielectric growth on graphene via atomic layer deposition (ALD), although the underlying chemical mechanisms and structural details of the molecule/dielectric interface remain unknown. Here, confocal resonance Raman spectroscopy is employed to quantify the structure and chemistry of monolayers of 3,4,9,10-perylenetetracarboxylic dianhydride (PTCDA) on graphene before and after deposition of alumina with the ALD precursors trimethyl aluminum (TMA) and water. Photoluminescence measurements provide further insight into the details of the growth mechanism, including the transition between layer-by-layer growth and island formation. Overall, these results reveal that PTCDA is not consumed during ALD, thereby preserving a well-defined and passivating organic interface between graphene and deposited dielectric thin films.
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1615
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Hsu PC, Wu H, Carney TJ, McDowell MT, Yang Y, Garnett EC, Li M, Hu L, Cui Y. Passivation coating on electrospun copper nanofibers for stable transparent electrodes. ACS NANO 2012; 6:5150-5156. [PMID: 22548313 DOI: 10.1021/nn300844g] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Copper nanofiber networks, which possess the advantages of low cost, moderate flexibility, small sheet resistance, and high transmittance, are one of the most promising candidates to replace indium tin oxide films as the premier transparent electrode. However, the chemical activity of copper nanofibers causes a substantial increase in the sheet resistance after thermal oxidation or chemical corrosion of the nanofibers. In this work, we utilize atomic layer deposition to coat a passivation layer of aluminum-doped zinc oxide (AZO) and aluminum oxide onto electrospun copper nanofibers and remarkably enhance their durability. Our AZO-copper nanofibers show resistance increase of remarkably only 10% after thermal oxidation at 160 °C in dry air and 80 °C in humid air with 80% relative humidity, whereas bare copper nanofibers quickly become insulating. In addition, the coating and baking of the acidic PEDOT:PSS layer on our fibers increases the sheet resistance of bare copper nanofibers by 6 orders of magnitude, while the AZO-Cu nanofibers show an 18% increase.
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Affiliation(s)
- Po-Chun Hsu
- Department of Materials Science and Engineering, Stanford University, Stanford, California 94305, USA
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1616
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Ruthenocene and cyclopentadienyl pyrrolyl ruthenium as precursors for ruthenium atomic layer deposition: a comparative study of dissociation enthalpies. Theor Chem Acc 2012. [DOI: 10.1007/s00214-012-1238-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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1617
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Luo J, Karuturi SK, Liu L, Su LT, Tok AIY, Fan HJ. Homogeneous photosensitization of complex TiO₂ nanostructures for efficient solar energy conversion. Sci Rep 2012; 2:451. [PMID: 22693653 PMCID: PMC3372876 DOI: 10.1038/srep00451] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2012] [Accepted: 05/23/2012] [Indexed: 11/09/2022] Open
Abstract
TiO₂ nanostructures-based photoelectrochemical (PEC) cells are under worldwide attentions as the method to generate clean energy. For these devices, narrow-bandgap semiconductor photosensitizers such as CdS and CdSe are commonly used to couple with TiO₂ in order to harvest the visible sunlight and to enhance the conversion efficiency. Conventional methods for depositing the photosensitizers on TiO₂ such as dip coating, electrochemical deposition and chemical-vapor-deposition suffer from poor control in thickness and uniformity, and correspond to low photocurrent levels. Here we demonstrate a new method based on atomic layer deposition and ion exchange reaction (ALDIER) to achieve a highly controllable and homogeneous coating of sensitizer particles on arbitrary TiO₂ substrates. PEC tests made to CdSe-sensitized TiO₂ inverse opal photoanodes result in a drastically improved photocurrent level, up to ~15.7 mA/cm² at zero bias (vs Ag/AgCl), more than double that by conventional techniques such as successive ionic layer adsorption and reaction.
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Affiliation(s)
- Jingshan Luo
- Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, 637371 Singapore
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1618
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Daly SR, Kim DY, Girolami GS. Lanthanide N,N-Dimethylaminodiboranates as a New Class of Highly Volatile Chemical Vapor Deposition Precursors. Inorg Chem 2012; 51:7050-65. [DOI: 10.1021/ic201852j] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Affiliation(s)
- Scott R. Daly
- The School of Chemical Sciences, University of Illinois at Urbana−Champaign, 600 South Mathews
Avenue, Urbana, Illinois 61801, United States
| | - Do Young Kim
- The School of Chemical Sciences, University of Illinois at Urbana−Champaign, 600 South Mathews
Avenue, Urbana, Illinois 61801, United States
| | - Gregory S. Girolami
- The School of Chemical Sciences, University of Illinois at Urbana−Champaign, 600 South Mathews
Avenue, Urbana, Illinois 61801, United States
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1619
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Daly SR, Bellott BJ, Nesbit MA, Girolami GS. Synthesis and Structural Diversity of Barium (N,N-Dimethylamino)diboranates. Inorg Chem 2012; 51:6449-59. [DOI: 10.1021/ic2016879] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Scott R. Daly
- The School of Chemical Sciences, University of Illinois at Urbana−Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801, United States
| | - Brian J. Bellott
- The School of Chemical Sciences, University of Illinois at Urbana−Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801, United States
| | - Mark A. Nesbit
- The School of Chemical Sciences, University of Illinois at Urbana−Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801, United States
| | - Gregory S. Girolami
- The School of Chemical Sciences, University of Illinois at Urbana−Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801, United States
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1620
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Yebo NA, Sree SP, Levrau E, Detavernier C, Hens Z, Martens JA, Baets R. Selective and reversible ammonia gas detection with nanoporous film functionalized silicon photonic micro-ring resonator. OPTICS EXPRESS 2012; 20:11855-62. [PMID: 22714172 DOI: 10.1364/oe.20.011855] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Portable, low cost and real-time gas sensors have a considerable potential in various biomedical and industrial applications. For such applications, nano-photonic gas sensors based on standard silicon fabrication technology offer attractive opportunities. Deposition of high surface area nano-porous coatings on silicon photonic sensors is a means to achieve selective, highly sensitive and multiplexed gas detection on an optical chip. Here we demonstrate selective and reversible ammonia gas detection with functionalized silicon-on-insulator optical micro-ring resonators. The micro-ring resonators are coated with acidic nano-porous aluminosilicate films for specific ammonia sensing, which results in a reversible response to NH(3)with selectivity relative to CO(2). The ammonia detection limit is estimated at about 5 ppm. The detectors reach a steady response to NH(3) within 30 and return to their base level within 60 to 90 seconds. The work opens perspectives on development of nano-photonic sensors for real-time, non-invasive, low cost and light weight biomedical and industrial sensing applications.
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Affiliation(s)
- Nebiyu A Yebo
- Ghent University-IMEC, Photonics Research group, INTEC, Sint-Pietersnieuwstraat 41, 9000 Gent, Belgium.
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1621
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Zaera F. The Surface Chemistry of Atomic Layer Depositions of Solid Thin Films. J Phys Chem Lett 2012; 3:1301-1309. [PMID: 26286774 DOI: 10.1021/jz300125f] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Atomic layer deposition (ALD) is one of the most promising methodologies available for the growth of solid thin films conformally on complex topographies and with atomic-level control on thickness. However, as a chemical process, ALD can lead to the incorporation of impurities and to the growth of poor-quality films. Here we discuss some possible complications associated with the chemistry of ALD, including its ill-defined stoichiometry, the stepwise and extensive surface conversion possible with the ligands of most ALD metalorganic precursors, the need for the reduction or oxidation of the deposited elements, the poor understanding of the role of the coreactants, the dominant activity of specific minority surface sites in starting ALD processes, and the development of complex layered or three-dimensional structures within the deposited films. The resolution of these issues should help with the development of a more systematic approach for the selection of ALD precursors and for the design of ALD processes.
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Affiliation(s)
- Francisco Zaera
- Department of Chemistry, University of California, Riverside, California 92521, United States
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1622
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Kilbury OJ, Barrett KS, Fu X, Yin J, Dinair DS, Gump CJ, Weimer AW, King DM. Atomic layer deposition of solid lubricating coatings on particles. POWDER TECHNOL 2012. [DOI: 10.1016/j.powtec.2011.12.021] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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1623
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1624
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Cronauer DC, Elam JW, Kropf AJ, Marshall CL, Gao P, Hopps S, Jacobs G, Davis BH. Fischer–Tropsch Synthesis: Preconditioning Effects Upon Co-Containing Promoted and Unpromoted Catalysts. Catal Letters 2012. [DOI: 10.1007/s10562-012-0818-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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1625
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Li F, Yang Y, Fan Y, Xing W, Wang Y. Modification of ceramic membranes for pore structure tailoring: The atomic layer deposition route. J Memb Sci 2012. [DOI: 10.1016/j.memsci.2012.01.005] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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1626
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Lu J, Fu B, Kung MC, Xiao G, Elam JW, Kung HH, Stair PC. Coking- and Sintering-Resistant Palladium Catalysts Achieved Through Atomic Layer Deposition. Science 2012; 335:1205-8. [DOI: 10.1126/science.1212906] [Citation(s) in RCA: 615] [Impact Index Per Article: 51.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
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1627
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Liu M, Li X, Karuturi SK, Tok AIY, Fan HJ. Atomic layer deposition for nanofabrication and interface engineering. NANOSCALE 2012; 4:1522-1528. [PMID: 22307135 DOI: 10.1039/c2nr11875k] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Atomic layer deposition (ALD) provides a tool for conformal coating on high aspect-ratio nanostructures with excellent uniformity. It has become a technique for both template-directed nanofabrications and engineering of surface properties. This Feature Article highlights the application of ALD in selected fields including photonics, SERS and energy materials. Specifically, the topics include fabrication of plasmonic nanostructures for the SERS applications, fabrication of 3-D nanoarchitectured photoanodes for solar energy conversions (dye-sensitized solar cells and photoelectrochemical cells), and coating of electrodes to enhance the cyclic stability and thus device life span of batteries. Dielectric coating for tailoring optical properties of semiconductor nanostructures is also discussed as exemplified by ZnO nanowires. Future direction of ALD in these applications is discussed at the end.
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Affiliation(s)
- Monan Liu
- Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, 637371, Singapore
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1628
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Lee HBR, Park YJ, Baik S, Kim H. Initial Stage Growth during Plasma-Enhanced Atomic Layer Deposition of Cobalt. ACTA ACUST UNITED AC 2012. [DOI: 10.1002/cvde.201106937] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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1629
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Lindquist NC, Nagpal P, McPeak KM, Norris DJ, Oh SH. Engineering metallic nanostructures for plasmonics and nanophotonics. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2012; 75:036501. [PMID: 22790420 PMCID: PMC3396886 DOI: 10.1088/0034-4885/75/3/036501] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
Metallic nanostructures now play an important role in many applications. In particular, for the emerging fields of plasmonics and nanophotonics, the ability to engineer metals on nanometric scales allows the development of new devices and the study of exciting physics. This review focuses on top-down nanofabrication techniques for engineering metallic nanostructures, along with computational and experimental characterization techniques. A variety of current and emerging applications are also covered.
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Affiliation(s)
- Nathan C Lindquist
- Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, MN, U.S.A
- Physics Department, Bethel University, St. Paul, MN, U.S.A
| | | | - Kevin M McPeak
- Optical Materials Engineering Laboratory, ETH Zürich, Zürich, Switzerland
| | - David J Norris
- Optical Materials Engineering Laboratory, ETH Zürich, Zürich, Switzerland
| | - Sang-Hyun Oh
- Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, MN, U.S.A
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1630
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Dendooven J, Devloo-Casier K, Levrau E, Van Hove R, Sree SP, Baklanov MR, Martens JA, Detavernier C. In situ monitoring of atomic layer deposition in nanoporous thin films using ellipsometric porosimetry. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2012; 28:3852-3859. [PMID: 22304361 DOI: 10.1021/la300045z] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Ellipsometric porosimetry (EP) is a handy technique to characterize the porosity and pore size distribution of porous thin films with pore diameters in the range from below 1 nm up to 50 nm and for the characterization of porous low-k films especially. Atomic layer deposition (ALD) can be used to functionalize porous films and membranes, e.g., for the development of filtration and sensor devices and catalytic surfaces. In this work we report on the implementation of the EP technique onto an ALD reactor. This combination allowed us to employ EP for monitoring the modification of a porous thin film through ALD without removing the sample from the deposition setup. The potential of in situ EP for providing information about the effect of ALD coating on the accessible porosity, the pore radius distribution, the thickness, and mechanical properties of a porous film is demonstrated in the ALD of TiO(2) in a mesoporous silica film.
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Affiliation(s)
- Jolien Dendooven
- Department of Solid State Sciences, COCOON, Ghent University, Krijgslaan 281/S1, B-9000 Ghent, Belgium.
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1631
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Im H, Wittenberg NJ, Lindquist NC, Oh SH. Atomic layer deposition (ALD): A versatile technique for plasmonics and nanobiotechnology. JOURNAL OF MATERIALS RESEARCH 2012; 27:663-671. [PMID: 22865951 PMCID: PMC3410655 DOI: 10.1557/jmr.2011.434] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
While atomic layer deposition (ALD) has been used for many years as an industrial manufacturing method for microprocessors and displays, this versatile technique is finding increased use in the emerging fields of plasmonics and nanobiotechnology. In particular, ALD coatings can modify metallic surfaces to tune their optical and plasmonic properties, to protect them against unwanted oxidation and contamination, or to create biocompatible surfaces. Furthermore, ALD is unique among thin-film deposition techniques in its ability to meet the processing demands for engineering nanoplasmonic devices, offering conformal deposition of dense and ultra-thin films on high-aspect-ratio nanostructures at temperatures below 100 °C. In this review, we present key features of ALD and describe how it could benefit future applications in plasmonics, nanosciences, and biotechnology.
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Affiliation(s)
- Hyungsoon Im
- Laboratory of Nanostructures and Biosensing, Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, MN 55455, United States
| | - Nathan J. Wittenberg
- Laboratory of Nanostructures and Biosensing, Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, MN 55455, United States
| | - Nathan C. Lindquist
- Laboratory of Nanostructures and Biosensing, Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, MN 55455, United States
- Department of Physics, Bethel University, St. Paul, MN 55112, United States
| | - Sang-Hyun Oh
- Laboratory of Nanostructures and Biosensing, Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, MN 55455, United States
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1632
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Klahr B, Gimenez S, Fabregat-Santiago F, Hamann T, Bisquert J. Water Oxidation at Hematite Photoelectrodes: The Role of Surface States. J Am Chem Soc 2012; 134:4294-302. [DOI: 10.1021/ja210755h] [Citation(s) in RCA: 745] [Impact Index Per Article: 62.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Benjamin Klahr
- Department of Chemistry, Michigan State University, East Lansing, Michigan 48824-1322,
United States
| | - Sixto Gimenez
- Photovoltaics and Optoelectronic
Devices Group, Departament de Física, Universitat Jaume I, 12071 Castelló, Spain
| | - Francisco Fabregat-Santiago
- Photovoltaics and Optoelectronic
Devices Group, Departament de Física, Universitat Jaume I, 12071 Castelló, Spain
| | - Thomas Hamann
- Department of Chemistry, Michigan State University, East Lansing, Michigan 48824-1322,
United States
| | - Juan Bisquert
- Photovoltaics and Optoelectronic
Devices Group, Departament de Física, Universitat Jaume I, 12071 Castelló, Spain
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1633
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Marichy C, Bechelany M, Pinna N. Atomic layer deposition of nanostructured materials for energy and environmental applications. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2012; 24:1017-32. [PMID: 22278762 DOI: 10.1002/adma.201104129] [Citation(s) in RCA: 141] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2011] [Indexed: 05/20/2023]
Abstract
Atomic layer deposition (ALD) is a thin film technology that in the past two decades rapidly developed from a niche technology to an established method. It proved to be a key technology for the surface modification and the fabrication of complex nanostructured materials. In this Progress Report, after a short introduction to ALD and its chemistry, the versatility of the technique for the fabrication of novel functional materials will be discussed. Selected examples, focused on its use for the engineering of nanostructures targeting applications in energy conversion and storage, and on environmental issues, will be discussed. Finally, the challenges that ALD is now facing in terms of materials fabrication and processing will be also tackled.
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Affiliation(s)
- Catherine Marichy
- Department of Chemistry, CICECO, University of Aveiro, Aveiro, Portugal
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1634
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Wegener SL, Marks TJ, Stair PC. Design strategies for the molecular level synthesis of supported catalysts. Acc Chem Res 2012; 45:206-14. [PMID: 22004451 DOI: 10.1021/ar2001342] [Citation(s) in RCA: 211] [Impact Index Per Article: 17.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Supported catalysts, metal or oxide catalytic centers constructed on an underlying solid phase, are making an increasingly important contribution to heterogeneous catalysis. For example, in industry, supported catalysts are employed in selective oxidation, selective reduction, and polymerization reactions. Supported structures increase the thermal stability, dispersion, and surface area of the catalyst relative to the neat catalytic material. However, structural and mechanistic characterization of these catalysts presents a formidable challenge because traditional preparations typically afford complex mixtures of structures whose individual components cannot be isolated. As a result, the characterization of supported catalysts requires a combination of advanced spectroscopies for their characterization, unlike homogeneous catalysts, which have relatively uniform structures and can often be characterized using standard methods. Moreover, these advanced spectroscopic techniques only provide ensemble averages and therefore do not isolate the catalytic function of individual components within the mixture. New synthetic approaches are required to more controllably tailor supported catalyst structures. In this Account, we review advances in supported catalyst synthesis and characterization developed in our laboratories at Northwestern University. We first present an overview of traditional synthetic methods with a focus on supported vanadium oxide catalysts. We next describe approaches for the design and synthesis of supported polymerization and hydrogenation catalysts, using anchoring techniques which provide molecular catalyst structures with exceptional activity and high percentages of catalytically significant sites. We then highlight similar approaches for preparing supported metal oxide catalysts using atomic layer deposition and organometallic grafting. Throughout this Account, we describe the use of incisive spectroscopic techniques, including high-resolution solid state NMR, UV-visible diffuse reflectance (DRS), UV-Raman, and X-ray absorption spectroscopies to characterize supported catalysts. We demonstrate that it is possible to tailor and isolate defined surface species using a molecularly oriented approach. We anticipate that advances in catalyst design and synthesis will lead to a better understanding of catalyst structure and function and, thus, to advances in existing catalytic processes and the development of new technologies.
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Affiliation(s)
- Staci L. Wegener
- Department of Chemistry and Center for Catalysis and Surface Science, Northwestern University, Evanston, Illinois 60208, United States
| | - Tobin J. Marks
- Department of Chemistry and Center for Catalysis and Surface Science, Northwestern University, Evanston, Illinois 60208, United States
| | - Peter C. Stair
- Department of Chemistry and Center for Catalysis and Surface Science, Northwestern University, Evanston, Illinois 60208, United States
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Argonne, Illinois 60439, United States
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1635
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Electrochemical Atomic Layer Deposition (E-ALD) of Palladium Nanofilms by Surface Limited Redox Replacement (SLRR), with EDTA Complexation. Electrocatalysis (N Y) 2012. [DOI: 10.1007/s12678-012-0080-7] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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1636
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Wang W, Tian M, Abdulagatov A, George SM, Lee YC, Yang R. Three-dimensional Ni/TiO2 nanowire network for high areal capacity lithium ion microbattery applications. NANO LETTERS 2012; 12:655-60. [PMID: 22208851 DOI: 10.1021/nl203434g] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
The areal capacity of nanowire-based microbatteries can be potentially increased by increasing the length of nanowires. However, agglomeration of high aspect ratio nanowire arrays could greatly degrade the performance of nanowires for lithium ion (Li-ion) battery applications. In this work, a three-dimensional (3-D) Ni/TiO(2) nanowire network was successfully fabricated using a 3-D porous anodic alumina (PAA) template-assisted electrodeposition of Ni followed by TiO(2) coating using atomic layer deposition. Compared to the straight Ni/TiO(2) nanowire arrays fabricated using conventional PAA templates, the 3-D Ni/TiO(2) nanowire network shows higher areal discharging capacity. The areal capacity increases proportionally with the length of nanowires. With a stable Ni/TiO(2) nanowire network structure, 100% capacity is retained after 600 cycles. This work paves the way to build reliable 3-D nanostructured electrodes for high areal capacity microbatteries.
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Affiliation(s)
- Wei Wang
- Department of Mechanical Engineering, University of Colorado, Boulder, Colorado 80309, USA
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1637
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Shviro M, Zitoun D. Low temperature, template-free route to nickel thin films and nanowires. NANOSCALE 2012; 4:762-767. [PMID: 22109737 DOI: 10.1039/c1nr11177a] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
In this manuscript, we report on the elaboration of nickel thin films, isolated clusters and nanowires on silicon, glass and polymers by a low temperature deposition technique. The process is based on the thermal decomposition of Ni (η(4)-C(8)H(12))(2) at temperatures as low as 80 °C, which exclusively yields metallic Ni and a volatile by-product. The low temperature of the process makes it compatible with most of the substrates, even polymers and organic layers. Several deposition techniques are explored, among them spin coating of the organometallic complex in solution, which allows controlling nickel film thickness down to several nanometers. The density of the film can be varied by the speed of the spin coater with the formation of nanowires being observed for an optimized speed. The nanowires form a network of parallel lines on silicon and the phenomenon will be discussed as a selective dewetting of the organometallic precursor. All samples are fully characterized by SEM, EDS, cross-sectional HRTEM, ellipsometry, AFM, MFM and SQUID magnetic measurements.
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Affiliation(s)
- Meital Shviro
- Bar Ilan University, Department of Chemistry and Bar Ilan Institute of Nanotechnology and Advanced Materials (BINA), Ramat Gan, 52900, Israel
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1638
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Venkatesan BM, Estrada D, Banerjee S, Jin X, Dorgan VE, Bae MH, Aluru NR, Pop E, Bashir R. Stacked graphene-Al2O3 nanopore sensors for sensitive detection of DNA and DNA-protein complexes. ACS NANO 2012; 6:441-50. [PMID: 22165962 PMCID: PMC3265664 DOI: 10.1021/nn203769e] [Citation(s) in RCA: 79] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
We report the development of a multilayered graphene-Al(2)O(3) nanopore platform for the sensitive detection of DNA and DNA-protein complexes. Graphene-Al(2)O(3) nanolaminate membranes are formed by sequentially depositing layers of graphene and Al(2)O(3), with nanopores being formed in these membranes using an electron-beam sculpting process. The resulting nanopores are highly robust, exhibit low electrical noise (significantly lower than nanopores in pure graphene), are highly sensitive to electrolyte pH at low KCl concentrations (attributed to the high buffer capacity of Al(2)O(3)), and permit the electrical biasing of the embedded graphene electrode, thereby allowing for three terminal nanopore measurements. In proof-of-principle biomolecule sensing experiments, the folded and unfolded transport of single DNA molecules and RecA-coated DNA complexes could be discerned with high temporal resolution. The process described here also enables nanopore integration with new graphene-based structures, including nanoribbons and nanogaps, for single-molecule DNA sequencing and medical diagnostic applications.
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Affiliation(s)
- Bala Murali Venkatesan
- Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, USA
- Micro and Nanotechnology Lab, University of Illinois at Urbana-Champaign, USA
| | - David Estrada
- Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, USA
- Micro and Nanotechnology Lab, University of Illinois at Urbana-Champaign, USA
| | - Shouvik Banerjee
- Micro and Nanotechnology Lab, University of Illinois at Urbana-Champaign, USA
- Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, USA
| | - Xiaozhong Jin
- Department of Mechanical Science and Engineering, University of Illinois at Urbana-Champaign, USA
- Beckman Institute, University of Illinois at Urbana-Champaign, USA
| | - Vincent E. Dorgan
- Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, USA
- Micro and Nanotechnology Lab, University of Illinois at Urbana-Champaign, USA
| | - Myung-Ho Bae
- Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, USA
- Micro and Nanotechnology Lab, University of Illinois at Urbana-Champaign, USA
| | - Narayana R. Aluru
- Department of Mechanical Science and Engineering, University of Illinois at Urbana-Champaign, USA
- Beckman Institute, University of Illinois at Urbana-Champaign, USA
| | - Eric Pop
- Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, USA
- Micro and Nanotechnology Lab, University of Illinois at Urbana-Champaign, USA
- Beckman Institute, University of Illinois at Urbana-Champaign, USA
| | - Rashid Bashir
- Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, USA
- Micro and Nanotechnology Lab, University of Illinois at Urbana-Champaign, USA
- Beckman Institute, University of Illinois at Urbana-Champaign, USA
- Department of Bioengineering, University of Illinois at Urbana-Champaign, USA
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1639
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Gai X, Wang RP, Xiong C, Steel MJ, Eggleton BJ, Luther-Davies B. Near-zero anomalous dispersion Ge11.5As24Se64.5 glass nanowires for correlated photon pair generation: design and analysis. OPTICS EXPRESS 2012; 20:776-786. [PMID: 22274423 DOI: 10.1364/oe.20.000776] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
We show that highly nonlinear chalcogenide glass nanowire waveguides with near-zero anomalous dispersion should be capable of generating correlated photon-pairs by spontaneous four-wave mixing at frequencies detuned by over 17 THz from the pump where Raman noise is absent. In this region we predict a photon pair correlation of >100, a figure of merit >10 and brightness of ~8×10(8) pairs/s over a bandwidth of >15 THz in nanowires with group velocity dispersion of <5 ps∙km(-1) nm(-1). We present designs for double-clad Ge(11.5)As(24)Se(64.5) glass nanowires with realistic tolerance to fabrication errors that achieve near-zero anomalous dispersion at a 1420 nm pump wavelength. This structure has a fabrication tolerance of 80-170 nm in the waveguide width and utilizes a SiO(2)/Al(2)O(3) layer deposited by atomic layer deposition to compensate the fabrication errors in the film thickness.
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Affiliation(s)
- X Gai
- Centre for Ultrahigh-bandwidth Devices for Optical Systems (CUDOS), Research School of Physics and Engineering, The Australian National University, Canberra ACT, Australia.
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1640
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Biswas A, Bayer IS, Biris AS, Wang T, Dervishi E, Faupel F. Advances in top-down and bottom-up surface nanofabrication: techniques, applications & future prospects. Adv Colloid Interface Sci 2012; 170:2-27. [PMID: 22154364 DOI: 10.1016/j.cis.2011.11.001] [Citation(s) in RCA: 301] [Impact Index Per Article: 25.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2011] [Revised: 11/02/2011] [Accepted: 11/08/2011] [Indexed: 02/02/2023]
Abstract
This review highlights the most significant advances of the nanofabrication techniques reported over the past decade with a particular focus on the approaches tailored towards the fabrication of functional nano-devices. The review is divided into two sections: top-down and bottom-up nanofabrication. Under the classification of top-down, special attention is given to technical reports that demonstrate multi-directional patterning capabilities less than or equal to 100 nm. These include recent advances in lithographic techniques, such as optical, electron beam, soft, nanoimprint, scanning probe, and block copolymer lithography. Bottom-up nanofabrication techniques--such as, atomic layer deposition, sol-gel nanofabrication, molecular self-assembly, vapor-phase deposition and DNA-scaffolding for nanoelectronics--are also discussed. Specifically, we describe advances in the fabrication of functional nanocomposites and graphene using chemical and physical vapor deposition. Our aim is to provide a comprehensive platform for prominent nanofabrication tools and techniques in order to facilitate the development of new or hybrid nanofabrication techniques leading to novel and efficient functional nanostructured devices.
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Affiliation(s)
- Abhijit Biswas
- Center for Nano Science and Technology (NDnano), Department of Electrical Engineering, University of Notre Dame, Notre Dame, IN 46556, USA.
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1641
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Rai VR, Vandalon V, Agarwal S. Influence of surface temperature on the mechanism of atomic layer deposition of aluminum oxide using an oxygen plasma and ozone. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2012; 28:350-357. [PMID: 22081861 DOI: 10.1021/la201136k] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
We have examined the role of substrate temperature on the surface reaction mechanisms during the atomic layer deposition (ALD) of Al(2)O(3) from trimethyl aluminum (TMA) in combination with an O(2) plasma and O(3) over a substrate temperature range of 70-200 °C. The ligand-exchange reactions were investigated using in situ attenuated total reflection Fourier transform infrared spectroscopy. Consistent with our previous work on ALD of Al(2)O(3) from an O(2) plasma and O(3) [Rai, V. R.; Vandalon, V.; Agarwal, S. Langmuir 2010, 26, 13732], both -OH groups and carbonates were the chemisorption sites for TMA over the entire temperature range explored. The concentration of surface -CH(3) groups after the TMA cycle was, however, strongly dependent on the surface temperature and the type of oxidizer, which in turn influenced the corresponding growth per cycle. The combustion of surface -CH(3) ligands was not complete at 70 °C during O(3) exposure, indicating that an O(2) plasma is a relatively stronger oxidizing agent. Further, in O(3)-assisted ALD, the ratio of mono- and bidentate carbonates on the surface after O(3) exposure was dependent on the substrate temperature.
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Affiliation(s)
- Vikrant R Rai
- Department of Chemical Engineering, Colorado School of Mines, Golden, Colorado 80401, United States
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1642
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Methaapanon R, Geyer SM, Lee HBR, Bent SF. The low temperature atomic layer deposition of ruthenium and the effect of oxygen exposure. ACTA ACUST UNITED AC 2012. [DOI: 10.1039/c2jm35332f] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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1643
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Kim SH, Yoon WM, Jang M, Yang H, Park JJ, Park CE. Damage-free hybrid encapsulation of organic field-effect transistors to reduce environmental instability. ACTA ACUST UNITED AC 2012. [DOI: 10.1039/c2jm13329f] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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1644
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Marichy C, Tessonnier JP, Ferro MC, Lee KH, Schlögl R, Pinna N, Willinger MG. Labeling and monitoring the distribution of anchoring sites on functionalized CNTs by atomic layer deposition. ACTA ACUST UNITED AC 2012. [DOI: 10.1039/c2jm00088a] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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1645
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Cyriac J, Wleklinski M, Li G, Gao L, Cooks RG. In situ Raman spectroscopy of surfaces modified by ion soft landing. Analyst 2012; 137:1363-9. [DOI: 10.1039/c2an16163j] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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1646
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Zydor A, Kessler VG, Elliott SD. First principles simulation of reaction steps in the atomic layer deposition of titania: dependence of growth on Lewis acidity of titanocene precursor. Phys Chem Chem Phys 2012; 14:7954-64. [DOI: 10.1039/c2cp40491e] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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1647
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Kao CY, Yoo JW, Min Y, Epstein AJ. Molecular layer deposition of an organic-based magnetic semiconducting laminate. ACS APPLIED MATERIALS & INTERFACES 2012; 4:137-41. [PMID: 22220500 DOI: 10.1021/am201506h] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Organic-based magnets are intriguing materials with unique magnetic and electronic properties that can be tailored by chemical methodology. By using molecular layer deposition (MLD), we demonstrate the thin film fabrication of V[TCNE: tetracyanoethylene](x), of the first known room temperature organic-based magnet. The resulting films exhibit improvement in surface morphology, larger coercivity (80 Oe), and higher Curie temperature/thermal stability (up to 400 K). Recently, the MLD method has been widely studied to implement fine control of organic film growth for various applications. This work broadens its application to magnetic and charge transfer materials and opens new opportunities for metal-organic hybrid material development and their applications in various multilayer film device structures. Finally, we demonstrate the applicability of the multilayer V[TCNE](x) as a spin injector combining LSMO, an standard inorganic magnetic semiconductor, for spintronics applications.
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Affiliation(s)
- Chi-Yueh Kao
- Department of Chemistry, The Ohio State University, Columbus, Ohio 43210-1173, USA
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1648
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1649
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Williams PA, Ireland CP, King PJ, Chater PA, Boldrin P, Palgrave RG, Claridge JB, Darwent JR, Chalker PR, Rosseinsky MJ. Atomic layer deposition of anatase TiO2 coating on silica particles: growth, characterization and evaluation as photocatalysts for methyl orange degradation and hydrogen production. ACTA ACUST UNITED AC 2012. [DOI: 10.1039/c2jm33446a] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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1650
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An Atomic Layer Deposition Method to Fabricate Economical and Robust Large Area Microchannel Plates for Photodetectors. ACTA ACUST UNITED AC 2012. [DOI: 10.1016/j.phpro.2012.03.720] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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