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Siles PF, Devarajulu M, Zhu F, Schmidt OG. Direct Imaging of Space-Charge Accumulation and Work Function Characteristics of Functional Organic Interfaces. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2018; 14:e1703647. [PMID: 29450970 DOI: 10.1002/smll.201703647] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2017] [Revised: 01/15/2018] [Indexed: 06/08/2023]
Abstract
The tailoring of organic systems is crucial to further extend the efficiency of charge transfer mechanisms and represents a cornerstone for molecular device technologies. However, this demands control of electrical properties and understanding of the physics behind organic interfaces. Here, a quantitative spatial overview of work function characteristics for phthalocyanine architectures on Au substrates is provided via kelvin probe microscopy. While macroscopic investigations are very informative, the current approach offers a nanoscale spatial rendering of electrical characteristics which is not possible to attain via conventional techniques. Interface dipole is observed due to the formation of charge accumulation layers in thin F16 CuPc, F16 CoPc, and MnPc films, displaying work functions of 5.7, 6.1, and 5.0 eV, respectively. The imaging and quantification of interface locations with significant surface potential and work function response (<0.33 eV for material thickness <1 nm) show also a dependency on the crystalline state of the organic systems. The work function mapping suggests space-charge carrier regions of about 4 nm at the organic interface. This reveals rich spatial electric parameters and ambipolar characteristics that may drive electrical performance at device scales, opening a realm of possibilities toward the development of functional organic architectures and its applications.
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Affiliation(s)
- Pablo F Siles
- Materials Systems for Nanoelectronics, Chemnitz University of Technology, 09107, Chemnitz, Germany
- Institute for Integrative Nanosciences, IFW Dresden, 01069, Dresden, Germany
| | - Mirunalini Devarajulu
- Materials Systems for Nanoelectronics, Chemnitz University of Technology, 09107, Chemnitz, Germany
- Institute for Integrative Nanosciences, IFW Dresden, 01069, Dresden, Germany
| | - Feng Zhu
- Materials Systems for Nanoelectronics, Chemnitz University of Technology, 09107, Chemnitz, Germany
- Institute for Integrative Nanosciences, IFW Dresden, 01069, Dresden, Germany
| | - Oliver G Schmidt
- Materials Systems for Nanoelectronics, Chemnitz University of Technology, 09107, Chemnitz, Germany
- Institute for Integrative Nanosciences, IFW Dresden, 01069, Dresden, Germany
- Center for Advancing Electronics Dresden (cfAED), TU Dresden, 01062, Dresden, Germany
- Faculty of Mechanical Engineering, Cluster of Excellence MERGE, Chemnitz University of Technology, 09107, Chemnitz, Germany
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2
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Rüffer T, Nurpeisova D, Jakupova Z, Tashenov A, Uhlig N, Khalladi A, Mertens L, Gonser A, Mehring M, Lang H. Synthesis and purification of metallooctachlorophthalocyanines. ZEITSCHRIFT FUR NATURFORSCHUNG SECTION B-A JOURNAL OF CHEMICAL SCIENCES 2017. [DOI: 10.1515/znb-2017-0068] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
A detailed synthetic procedure based on the use of urea, dichlorophthalic acid, respective transition metal halides and [NH4]2[MoO4] as a catalyst in the melt or by using 1,2,4-trichlorobenzene as a high-boiling inert solvent is described to gain 2,3,9,10,16,17,23,24-metallooctachlorophthalocyanines (MPcCl8 compounds with M=Mn, Fe, Co, Ni, Cu). In cases that a first purification by subsequent treatment of the crude materials with HCl, NaOH and HCl would not give rise to analytically pure compounds, a second novel purification by using pyridine is described. The degree of purity, exceeding always 98%, is determined by thermogravimetric analysis. Comparative IR, UV/Vis and PXRD studies of the MPcCl8 compounds are reported.
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Affiliation(s)
- Tobias Rüffer
- Technische Universität Chemnitz , Fakultät für Naturwissenschaften, Institut für Chemie, Anorganische Chemie , Straße der Nationen 62 , D-09111 Chemnitz , Germany
| | - Dinara Nurpeisova
- L. N. Gumilyov Eurasian National University , Astana 010008 , Republic of Kazakhstan
| | - Zhanar Jakupova
- L. N. Gumilyov Eurasian National University , Astana 010008 , Republic of Kazakhstan
| | - Ayezkhan Tashenov
- L. N. Gumilyov Eurasian National University , Astana 010008 , Republic of Kazakhstan
| | - Nell Uhlig
- Technische Universität Chemnitz, Fakultät für Naturwissenschaften, Institut für Chemie , Anorganische Chemie, D-09111 Chemnitz , Germany
| | - Ahmed Khalladi
- Technische Universität Chemnitz, Fakultät für Naturwissenschaften, Institut für Chemie , Anorganische Chemie, D-09111 Chemnitz , Germany
| | - Lutz Mertens
- Technische Universität Chemnitz , Fakultät für Naturwissenschaften, Institut für Chemie, Koordinationschemie , D-09111 Chemnitz , Germany
| | - Andreas Gonser
- Technische Universität Chemnitz, Fakultät für Naturwissenschaften, Institut für Chemie , Anorganische Chemie, D-09111 Chemnitz , Germany
- Robert Bosch GmbH , Robert-Bosch-Campus 1 , 71272 Renningen , Germany
| | - Michael Mehring
- Technische Universität Chemnitz , Fakultät für Naturwissenschaften, Institut für Chemie, Koordinationschemie , D-09111 Chemnitz , Germany
| | - Heinrich Lang
- Technische Universität Chemnitz, Fakultät für Naturwissenschaften, Institut für Chemie , Anorganische Chemie, D-09111 Chemnitz , Germany
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3
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Rückerl F, Waas D, Büchner B, Knupfer M, Zahn DRT, Haidu F, Hahn T, Kortus J. Charge transfer from and to manganese phthalocyanine: bulk materials and interfaces. BEILSTEIN JOURNAL OF NANOTECHNOLOGY 2017; 8:1601-1615. [PMID: 28884064 PMCID: PMC5550819 DOI: 10.3762/bjnano.8.160] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2017] [Accepted: 06/13/2017] [Indexed: 05/09/2023]
Abstract
Manganese phthalocyanine (MnPc) is a member of the family of transition-metal phthalocyanines, which combines interesting electronic behavior in the fields of organic and molecular electronics with local magnetic moments. MnPc is characterized by hybrid states between the Mn 3d orbitals and the π orbitals of the ligand very close to the Fermi level. This causes particular physical properties, different from those of the other phthalocyanines, such as a rather small ionization potential, a small band gap and a large electron affinity. These can be exploited to prepare particular compounds and interfaces with appropriate partners, which are characterized by a charge transfer from or to MnPc. We summarize recent spectroscopic and theoretical results that have been achieved in this regard.
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Affiliation(s)
| | - Daniel Waas
- IFW Dresden, Helmholtzstr. 20, D-01069 Dresden, Germany
| | - Bernd Büchner
- IFW Dresden, Helmholtzstr. 20, D-01069 Dresden, Germany
| | | | - Dietrich R T Zahn
- Semiconductor Physics, Chemnitz University of Technology, D-09107 Chemnitz, Germany
| | - Francisc Haidu
- Semiconductor Physics, Chemnitz University of Technology, D-09107 Chemnitz, Germany
| | - Torsten Hahn
- Institute of Theoretical Physics, TU Bergakademie Freiberg, Leipziger Str. 23, D-09596 Freiberg, Germany
| | - Jens Kortus
- Institute of Theoretical Physics, TU Bergakademie Freiberg, Leipziger Str. 23, D-09596 Freiberg, Germany
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4
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Dhara B, Tarafder K, Jha PK, Panja SN, Nair S, Oppeneer PM, Ballav N. Possible Room-Temperature Ferromagnetism in Self-Assembled Ensembles of Paramagnetic and Diamagnetic Molecular Semiconductors. J Phys Chem Lett 2016; 7:4988-4995. [PMID: 27973877 DOI: 10.1021/acs.jpclett.6b02063] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Owing to long spin-relaxation time and chemically customizable physical properties, molecule-based semiconductor materials like metal-phthalocyanines offer promising alternatives to conventional dilute magnetic semiconductors/oxides (DMSs/DMOs) to achieve room-temperature (RT) ferromagnetism. However, air-stable molecule-based materials exhibiting both semiconductivity and magnetic-order at RT have so far remained elusive. We present here the concept of supramolecular arrangement to accomplish possibly RT ferromagnetism. Specifically, we observe a clear hysteresis-loop (Hc ≈ 120 Oe) at 300 K in the magnetization versus field (M-H) plot of the self-assembled ensembles of diamagnetic Zn-phthalocyanine having peripheral F atoms (ZnFPc; S = 0) and paramagnetic Fe-phthalocyanine having peripehral H atoms (FePc; S = 1). Tauc plot of the self-assembled FePc···ZnFPc ensembles showed an optical band gap of ∼1.05 eV and temperature-dependent current-voltage (I-V) studies suggest semiconducting characteristics in the material. Using DFT+U quantum-chemical calculations, we reveal the origin of such unusual ferromagnetic exchange-interaction in the supramolecular FePc···ZnFPc system.
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Affiliation(s)
- Barun Dhara
- Department of Chemistry, Indian Institute of Science Education and Research (IISER) , Pune 411008, India
| | - Kartick Tarafder
- Department of Physics, National Institute of Technology Karnataka (NITK) , Mangalore 575 025, India
| | - Plawan K Jha
- Department of Chemistry, Indian Institute of Science Education and Research (IISER) , Pune 411008, India
| | - Soumendra N Panja
- Department of Physics, Indian Institute of Science Education and Research (IISER) , Pune 411008, India
| | - Sunil Nair
- Department of Physics, Indian Institute of Science Education and Research (IISER) , Pune 411008, India
| | - Peter M Oppeneer
- Department of Physics and Astronomy, Uppsala University , Box 516, S-751 20 Uppsala, Sweden
| | - Nirmalya Ballav
- Department of Chemistry, Indian Institute of Science Education and Research (IISER) , Pune 411008, India
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Rückerl F, Mahns B, Dodbiba E, Nikolis V, Herzig M, Büchner B, Knupfer M, Hahn T, Kortus J. Electronic properties of the charge transfer material MnPc/F4TCNQ. J Chem Phys 2016. [DOI: 10.1063/1.4962578] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Florian Rückerl
- Institute for Solid State Research, IFW-Dresden, Helmholtzstraße 20, P.O. Box 270116, DE-01171 Dresden, Germany
| | - Benjamin Mahns
- Institute for Solid State Research, IFW-Dresden, Helmholtzstraße 20, P.O. Box 270116, DE-01171 Dresden, Germany
| | - Eni Dodbiba
- Institute for Solid State Research, IFW-Dresden, Helmholtzstraße 20, P.O. Box 270116, DE-01171 Dresden, Germany
| | - Vasileios Nikolis
- Institute for Solid State Research, IFW-Dresden, Helmholtzstraße 20, P.O. Box 270116, DE-01171 Dresden, Germany
| | - Melanie Herzig
- Institute for Solid State Research, IFW-Dresden, Helmholtzstraße 20, P.O. Box 270116, DE-01171 Dresden, Germany
| | - Bernd Büchner
- Institute for Solid State Research, IFW-Dresden, Helmholtzstraße 20, P.O. Box 270116, DE-01171 Dresden, Germany
| | - Martin Knupfer
- Institute for Solid State Research, IFW-Dresden, Helmholtzstraße 20, P.O. Box 270116, DE-01171 Dresden, Germany
| | - Torsten Hahn
- Institute of Theoretical Physics, TU Bergakademie Freiberg, Leipziger Str. 23, DE-09596 Freiberg, Germany
| | - Jens Kortus
- Institute of Theoretical Physics, TU Bergakademie Freiberg, Leipziger Str. 23, DE-09596 Freiberg, Germany
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Siles PF, Hahn T, Salvan G, Knupfer M, Zhu F, Zahn DRT, Schmidt OG. Tunable charge transfer properties in metal-phthalocyanine heterojunctions. NANOSCALE 2016; 8:8607-8617. [PMID: 27049842 DOI: 10.1039/c5nr08671j] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Organic materials such as phthalocyanine-based systems present a great potential for organic device applications due to the possibility of integrating films of different organic materials to create organic heterostructures which combine the electrical capabilities of each material. This opens the possibility to precisely engineer and tune new electrical properties. In particular, similar transition metal phthalocyanines demonstrate hybridization and charge transfer properties which could lead to interesting physical phenomena. Although, when considering device dimensions, a better understanding and control of the tuning of the transport properties still remain in the focus of research. Here, by employing conductive atomic force microscopy techniques, we provide an insight about the nanoscale electrical properties and transport mechanisms of MnPc and fluorinated phthalocyanines such as F16CuPc and F16CoPc. We report a transition from typical diode-like transport mechanisms for pure MnPc thin films to space-charge-limited current transport regime (SCLC) for Pc-based heterostructures. The controlled addition of fluorinated phthalocyanine also provides highly uniform and symmetric-polarized transport characteristics with conductance enhancements up to two orders of magnitude depending on the polarization. We present a method to spatially map the mobility of the MnPc/F16CuPc structures with a nanoscale resolution and provide theoretical calculations to support our experimental findings. This well-controlled nanoscale tuning of the electrical properties for metal transition phthalocyanine junctions stands as key step for future phthalocyanine-based electronic devices, where the low dimension charge transfer, mediated by transition metal atoms could be intrinsically linked to a transfer of magnetic moment or spin.
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Affiliation(s)
- P F Siles
- Material Systems for Nanoelectronics, Technische Universität Chemnitz, 09107 Chemnitz, Germany. and Institute for Integrative Nanosciences, IFW Dresden, 01069 Dresden, Germany
| | - T Hahn
- Institute of Theoretical Physics, TU Bergakademie Freiberg, 09696 Freiberg, Germany
| | - G Salvan
- Semiconductor Physics, Technische Universität Chemnitz, 09107 Chemnitz, Germany
| | - M Knupfer
- Institute for Integrative Nanosciences, IFW Dresden, 01069 Dresden, Germany
| | - F Zhu
- Material Systems for Nanoelectronics, Technische Universität Chemnitz, 09107 Chemnitz, Germany. and Institute for Integrative Nanosciences, IFW Dresden, 01069 Dresden, Germany
| | - D R T Zahn
- Semiconductor Physics, Technische Universität Chemnitz, 09107 Chemnitz, Germany and Center for Advancing Electronics Dresden (cfAED), TU Dresden, 01062 Dresden, Germany and Faculty of Mechanical Engineering, Cluster of Excellence MERGE, Technische Universität Chemnitz, 09107 Chemnitz, Germany
| | - O G Schmidt
- Material Systems for Nanoelectronics, Technische Universität Chemnitz, 09107 Chemnitz, Germany. and Institute for Integrative Nanosciences, IFW Dresden, 01069 Dresden, Germany and Center for Advancing Electronics Dresden (cfAED), TU Dresden, 01062 Dresden, Germany and Faculty of Mechanical Engineering, Cluster of Excellence MERGE, Technische Universität Chemnitz, 09107 Chemnitz, Germany
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7
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Zhong JQ, Wang Z, Zhang JL, Wright CA, Yuan K, Gu C, Tadich A, Qi D, Li HX, Lai M, Wu K, Xu GQ, Hu W, Li Z, Chen W. Reversible Tuning of Interfacial and Intramolecular Charge Transfer in Individual MnPc Molecules. NANO LETTERS 2015; 15:8091-8098. [PMID: 26528623 DOI: 10.1021/acs.nanolett.5b03520] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The reversible selective hydrogenation and dehydrogenation of individual manganese phthalocyanine (MnPc) molecules has been investigated using photoelectron spectroscopy (PES), low-temperature scanning tunneling microscopy (LT-STM), synchrotron-based near edge X-ray absorption fine structure (NEXAFS) measurements, and supported by density functional theory (DFT) calculations. It is shown conclusively that interfacial and intramolecular charge transfer arises during the hydrogenation process. The electronic energetics upon hydrogenation is identified, enabling a greater understanding of interfacial and intramolecular charge transportation in the field of single-molecule electronics.
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Affiliation(s)
- Jian-Qiang Zhong
- School of Physics and Optoelectronic Engineering, Nanjing University of Information Science and Technology , Nanjing, Jiangsu 210044, China
- Department of Chemistry, National University of Singapore , 3 Science Drive 3, 117543, Singapore
- Department of Physics, National University of Singapore , 2 Science Drive 3, 117542, Singapore
| | - Zhunzhun Wang
- Hefei National Laboratory for Physical Sciences at Microscale, University of Science and Technology of China , Hefei 230026, China
- Guizhou Provincial Key Laboratory of Computational Nanomaterial Science, Guizhou Normal College , Guiyang 550018, China
| | - Jia Lin Zhang
- Department of Chemistry, National University of Singapore , 3 Science Drive 3, 117543, Singapore
- Department of Physics, National University of Singapore , 2 Science Drive 3, 117542, Singapore
| | - Christopher A Wright
- Department of Chemistry and Physics, La Trobe Institute for Molecular Science, La Trobe University , Melbourne, Victoria 3086, Australia
| | - Kaidi Yuan
- Department of Physics, National University of Singapore , 2 Science Drive 3, 117542, Singapore
| | - Chengding Gu
- Department of Chemistry, National University of Singapore , 3 Science Drive 3, 117543, Singapore
| | - Anton Tadich
- Department of Chemistry and Physics, La Trobe Institute for Molecular Science, La Trobe University , Melbourne, Victoria 3086, Australia
- Australian Synchrotron , 800 Blackburn Road, Clayton, Victoria 3168, Australia
| | - Dongchen Qi
- Department of Chemistry and Physics, La Trobe Institute for Molecular Science, La Trobe University , Melbourne, Victoria 3086, Australia
| | - He Xing Li
- Chinese Education Ministry Key Laboratory of Resource Chemistry, Shanghai Normal University , Shanghai 200234, China
| | - Min Lai
- School of Physics and Optoelectronic Engineering, Nanjing University of Information Science and Technology , Nanjing, Jiangsu 210044, China
| | - Kai Wu
- College of Chemistry and Molecular Engineering, Peking University , Beijing 100871, China
- Singapore-Peking University Research Center for a Sustainable Low-Carbon Future , 1 CREAT Way, #15-01, CREAT Tower, 138602, Singapore
| | - Guo Qin Xu
- Department of Chemistry, National University of Singapore , 3 Science Drive 3, 117543, Singapore
- Singapore-Peking University Research Center for a Sustainable Low-Carbon Future , 1 CREAT Way, #15-01, CREAT Tower, 138602, Singapore
- National University of Singapore (Suzhou) Research Institute , 377 Lin Quan Street, Suzhou Industrial Park, Jiangsu 215123, China
| | - Wenping Hu
- Department of Chemistry, School of Science, Tianjin University and Collaborative Innovation Center of Chemical Science and Engineering (Tianjin) , Tianjin 300072, China
| | - Zhenyu Li
- Hefei National Laboratory for Physical Sciences at Microscale, University of Science and Technology of China , Hefei 230026, China
| | - Wei Chen
- Department of Chemistry, National University of Singapore , 3 Science Drive 3, 117543, Singapore
- Department of Physics, National University of Singapore , 2 Science Drive 3, 117542, Singapore
- Singapore-Peking University Research Center for a Sustainable Low-Carbon Future , 1 CREAT Way, #15-01, CREAT Tower, 138602, Singapore
- National University of Singapore (Suzhou) Research Institute , 377 Lin Quan Street, Suzhou Industrial Park, Jiangsu 215123, China
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Lindner S, Mahns B, Treske U, Vilkov O, Haidu F, Fronk M, Zahn DRT, Knupfer M. Epitaxial growth and electronic properties of well ordered phthalocyanine heterojunctions MnPc/F16CoPc. J Chem Phys 2014; 141:094706. [DOI: 10.1063/1.4894757] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Susi Lindner
- IFW Dresden, P.O. Box 270116, D-01171 Dresden, Germany
| | | | - Uwe Treske
- IFW Dresden, P.O. Box 270116, D-01171 Dresden, Germany
| | - Oleg Vilkov
- Center for Physical Methods of Surface Investigation, St. Petersburg State University, Ulyanovskaya Str. 1, St. Petersburg 198504, Russia and Institute of Solid State Physics, University of Technology Dresden, Zellescher Weg 16, D-01062 Dresden, Germany
| | - Francisc Haidu
- Physics Department/Semiconductor Physics, Chemnitz University of Technology, Reichenhainer Str. 70, D-09126 Chemnitz, Germany
| | - Michael Fronk
- Physics Department/Semiconductor Physics, Chemnitz University of Technology, Reichenhainer Str. 70, D-09126 Chemnitz, Germany
| | - Dietrich R. T. Zahn
- Physics Department/Semiconductor Physics, Chemnitz University of Technology, Reichenhainer Str. 70, D-09126 Chemnitz, Germany
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