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Kim JH, Halaksa R, Jo IY, Ahn H, Gilhooly-Finn PA, Lee I, Park S, Nielsen CB, Yoon MH. Peculiar transient behaviors of organic electrochemical transistors governed by ion injection directionality. Nat Commun 2023; 14:7577. [PMID: 38016963 PMCID: PMC10684893 DOI: 10.1038/s41467-023-42840-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2023] [Accepted: 10/24/2023] [Indexed: 11/30/2023] Open
Abstract
Despite the growing interest in dynamic behaviors at the frequency domain, there exist very few studies on molecular orientation-dependent transient responses of organic mixed ionic-electronic conductors. In this research, we investigated the effect of ion injection directionality on transient electrochemical transistor behaviors by developing a model mixed conductor system. Two polymers with similar electrical, ionic, and electrochemical characteristics but distinct backbone planarities and molecular orientations were successfully synthesized by varying the co-monomer unit (2,2'-bithiophene or phenylene) in conjunction with a novel 1,4-dithienylphenylene-based monomer. The comprehensive electrochemical analysis suggests that the molecular orientation affects the length of the ion-drift pathway, which is directly correlated with ion mobility, resulting in peculiar OECT transient responses. These results provide the general insight into molecular orientation-dependent ion movement characteristics as well as high-performance device design principles with fine-tuned transient responses.
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Affiliation(s)
- Ji Hwan Kim
- School of Materials Science and Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju, 61005, Republic of Korea
| | - Roman Halaksa
- Department of Chemistry, Queen Mary University of London, London, E1 4NS, UK
| | - Il-Young Jo
- School of Materials Science and Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju, 61005, Republic of Korea
| | - Hyungju Ahn
- Pohang Accelerator Laboratory, Pohang, 37673, Republic of Korea
| | | | - Inho Lee
- Department of Intelligence Semiconductor Engineering, Ajou University, Suwon, 16499, Republic of Korea
| | - Sungjun Park
- Department of Intelligence Semiconductor Engineering, Ajou University, Suwon, 16499, Republic of Korea
- Department of Electrical and Computer Engineering, Ajou University, Suwon, 16499, Republic of Korea
| | - Christian B Nielsen
- Department of Chemistry, Queen Mary University of London, London, E1 4NS, UK.
| | - Myung-Han Yoon
- School of Materials Science and Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju, 61005, Republic of Korea.
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2
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Halaksa R, Kim JH, Thorley KJ, Gilhooly‐Finn PA, Ahn H, Savva A, Yoon M, Nielsen CB. The Influence of Regiochemistry on the Performance of Organic Mixed Ionic and Electronic Conductors. ANGEWANDTE CHEMIE (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2023; 135:e202304390. [PMID: 38528843 PMCID: PMC10962556 DOI: 10.1002/ange.202304390] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Indexed: 03/27/2024]
Abstract
Thiophenes functionalised in the 3-position are ubiquitous building blocks for the design and synthesis of organic semiconductors. Their non-centrosymmetric nature has long been used as a powerful synthetic design tool exemplified by the vastly different properties of regiorandom and regioregular poly(3-hexylthiophene) owing to the repulsive head-to-head interactions between neighbouring side chains in the regiorandom polymer. The renewed interest in highly electron-rich 3-alkoxythiophene based polymers for bioelectronic applications opens up new considerations around the regiochemistry of these systems as both the head-to-tail and head-to-head couplings adopt near-planar conformations due to attractive intramolecular S-O interactions. To understand how this increased flexibility in the molecular design can be used advantageously, we explore in detail the geometrical and electronic effects that influence the optical, electrochemical, structural, and electrical properties of a series of six polythiophene derivatives with varying regiochemistry and comonomer composition. We show how the interplay between conformational disorder, backbone coplanarity and polaron distribution affects the mixed ionic-electronic conduction. Ultimately, we use these findings to identify a new conformationally restricted polythiophene derivative for p-type accumulation-mode organic electrochemical transistor applications with performance on par with state-of-the-art mixed conductors evidenced by a μC* product of 267 F V-1 cm-1 s-1.
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Affiliation(s)
- Roman Halaksa
- Department of ChemistryQueen Mary University of LondonMile End RoadLondonE1 4NSUK
| | - Ji Hwan Kim
- School of Materials Science and EngineeringGwangju Institute of Science and Technology (GIST)123 Cheomdangwagi-ro, Buk-guGwangju61005Republic of Korea
| | - Karl J. Thorley
- Center for Applied Energy ResearchUniversity of KentuckyLexingtonKY40511USA
| | | | - Hyungju Ahn
- Pohang Accelerator Laboratory, POSTECHPohang37673Republic of Korea
| | - Achilleas Savva
- Department of Chemical Engineering and BiotechnologyUniversity of CambridgeCambridgeCB3 0ASUK
| | - Myung‐Han Yoon
- School of Materials Science and EngineeringGwangju Institute of Science and Technology (GIST)123 Cheomdangwagi-ro, Buk-guGwangju61005Republic of Korea
| | - Christian B. Nielsen
- Department of ChemistryQueen Mary University of LondonMile End RoadLondonE1 4NSUK
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3
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Halaksa R, Kim JH, Thorley KJ, Gilhooly‐Finn PA, Ahn H, Savva A, Yoon M, Nielsen CB. The Influence of Regiochemistry on the Performance of Organic Mixed Ionic and Electronic Conductors. Angew Chem Int Ed Engl 2023; 62:e202304390. [PMID: 37204070 PMCID: PMC10962546 DOI: 10.1002/anie.202304390] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Revised: 05/11/2023] [Accepted: 05/17/2023] [Indexed: 05/20/2023]
Abstract
Thiophenes functionalised in the 3-position are ubiquitous building blocks for the design and synthesis of organic semiconductors. Their non-centrosymmetric nature has long been used as a powerful synthetic design tool exemplified by the vastly different properties of regiorandom and regioregular poly(3-hexylthiophene) owing to the repulsive head-to-head interactions between neighbouring side chains in the regiorandom polymer. The renewed interest in highly electron-rich 3-alkoxythiophene based polymers for bioelectronic applications opens up new considerations around the regiochemistry of these systems as both the head-to-tail and head-to-head couplings adopt near-planar conformations due to attractive intramolecular S-O interactions. To understand how this increased flexibility in the molecular design can be used advantageously, we explore in detail the geometrical and electronic effects that influence the optical, electrochemical, structural, and electrical properties of a series of six polythiophene derivatives with varying regiochemistry and comonomer composition. We show how the interplay between conformational disorder, backbone coplanarity and polaron distribution affects the mixed ionic-electronic conduction. Ultimately, we use these findings to identify a new conformationally restricted polythiophene derivative for p-type accumulation-mode organic electrochemical transistor applications with performance on par with state-of-the-art mixed conductors evidenced by a μC* product of 267 F V-1 cm-1 s-1 .
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Affiliation(s)
- Roman Halaksa
- Department of ChemistryQueen Mary University of LondonMile End RoadLondonE1 4NSUK
| | - Ji Hwan Kim
- School of Materials Science and EngineeringGwangju Institute of Science and Technology (GIST)123 Cheomdangwagi-ro, Buk-guGwangju61005Republic of Korea
| | - Karl J. Thorley
- Center for Applied Energy ResearchUniversity of KentuckyLexingtonKY40511USA
| | | | - Hyungju Ahn
- Pohang Accelerator Laboratory, POSTECHPohang37673Republic of Korea
| | - Achilleas Savva
- Department of Chemical Engineering and BiotechnologyUniversity of CambridgeCambridgeCB3 0ASUK
| | - Myung‐Han Yoon
- School of Materials Science and EngineeringGwangju Institute of Science and Technology (GIST)123 Cheomdangwagi-ro, Buk-guGwangju61005Republic of Korea
| | - Christian B. Nielsen
- Department of ChemistryQueen Mary University of LondonMile End RoadLondonE1 4NSUK
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Camero DM, Grinalds NJ, Kornman CT, Barba S, Li L, Weldeab AO, Castellano RK, Xue J. Thin-Film Morphology and Optical Properties of Photoisomerizable Donor-Acceptor Oligothiophenes. ACS APPLIED MATERIALS & INTERFACES 2023; 15:25134-25147. [PMID: 35766151 DOI: 10.1021/acsami.2c05946] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
It was recently reported that the most popular electron-accepting units introduced to π-conjugated oligomers studied for organic photovoltaic applications are susceptible to unwanted and even destructive photochemical reactions. The consequences of Z/E photoisomerization of the popular 2-(1,1-dicyanomethylene)rhodanine (RCN) unit on the optical and morphological properties of a homologous series of RCN-functionalized oligothiophenes are studied here. Oligomers consisting of one, two, or three thiophene units were studied as pure Z isomers and with E isomer compositions of 25, 53, and 45%, respectively, for Z/E mixtures. Solutions of Z isomers and Z/E mixtures were characterized by UV-vis and photoluminescence spectroscopy, wherein changes to optical properties were evaluated on the basis of E isomer content. X-ray diffraction of thin-film Z/E mixtures reveals crystalline domains of both Z and E forms after thermal annealing for mono- and bithiophene oligomers, with greater interplanar spacing for E crystalline domains than the Z counterparts along the substrate normal direction. The surface morphology viewed by atomic force microscopy also shows fiberlike structures for the E form with a much larger aspect ratio than for the Z domains in the bithiophene oligomer. Optical characterization reveals drastic changes in the solid state upon introduction of the E form for the mono- and bithiophene derivatives, whereas subtle consequences are noted for the terthiophene analogue. Most notably, a 132 nm redshift in maximum absorption occurs for the bithiophene oligomer films containing 53% E isomer compared to the pure Z counterpart. Finally, although solid-state photoisomerization experiments find no evidence of Z → E isomerization in polycrystalline Z films, E → Z isomerization is observed and becomes more restrictive in films with higher crystallinity (i.e., after thermal annealing). This structure-property study, which elucidates the consequences of the RCN configuration on solid-state packing and optical properties, is expected to guide the development of more efficient and stable organic optoelectronic devices.
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Affiliation(s)
- David M Camero
- Department of Materials Science and Engineering, University of Florida, PO Box 116400, Gainesville, Florida 32611, United States
| | - Nathan J Grinalds
- Department of Materials Science and Engineering, University of Florida, PO Box 116400, Gainesville, Florida 32611, United States
| | - Cory T Kornman
- Department of Chemistry, University of Florida, PO Box 117200, Gainesville, Florida 32611, United States
| | - Stefano Barba
- Department of Materials Science and Engineering, University of Florida, PO Box 116400, Gainesville, Florida 32611, United States
| | - Lei Li
- Department of Chemistry, University of Florida, PO Box 117200, Gainesville, Florida 32611, United States
- Department of Materials Science and Engineering, Center for Optical Materials Science and Engineering Technologies (COMSET), Clemson University, Clemson, South Carolina 29634, United States
| | - Asmerom O Weldeab
- Department of Chemistry, University of Florida, PO Box 117200, Gainesville, Florida 32611, United States
| | - Ronald K Castellano
- Department of Chemistry, University of Florida, PO Box 117200, Gainesville, Florida 32611, United States
| | - Jiangeng Xue
- Department of Materials Science and Engineering, University of Florida, PO Box 116400, Gainesville, Florida 32611, United States
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5
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The Adsorption and Electropolymerization of Terthiophene on Au(111) Electrode – Probed by in situ STM. J Electroanal Chem (Lausanne) 2022. [DOI: 10.1016/j.jelechem.2022.116651] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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6
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Ohno S, Tanaka H, Tanaka K, Takahashi K, Tanaka M. Electronic structure of α-sexithiophene ultrathin films grown on. Phys Chem Chem Phys 2018; 20:1114-1126. [DOI: 10.1039/c7cp05222g] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
We investigated the electronic states of α-sexithiophene (α-6T) on by means of angle-resolved photoelectron spectroscopy using synchrotron radiation.
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Affiliation(s)
- Shinya Ohno
- Faculty of Engineering
- Yokohama National University
- Yokohama 240-8501
- Japan
| | - Hiroya Tanaka
- Faculty of Engineering
- Yokohama National University
- Yokohama 240-8501
- Japan
| | - Kazuma Tanaka
- Faculty of Engineering
- Yokohama National University
- Yokohama 240-8501
- Japan
| | | | - Masatoshi Tanaka
- Faculty of Engineering
- Yokohama National University
- Yokohama 240-8501
- Japan
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7
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Pan Y, Kanisawa K, Ishikawa N, Fölsch S. Scanning tunnelling spectroscopy and manipulation of double-decker phthalocyanine molecules on a semiconductor surface. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2017; 29:364001. [PMID: 28677593 DOI: 10.1088/1361-648x/aa7dc4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
A scanning tunnelling microscope (STM) operated at 5 K was used to study dysprosium biphthalocyanine (DyPc2) molecules adsorbed on the inert III-V semiconductor surface InAs(1 1 1)A. Orbital imaging and scanning tunnelling spectroscopy measurements reveal that the molecular electronic structure remains largely unperturbed, indicating a weak molecule-surface binding. The molecule adsorbs at the In vacancy site of the (2 × 2)-reconstructed surface and is highly sensitive to current-induced excitations leading to random rotational fluctuations. Owing to the weak surface binding, individual molecules can be precisely repositioned and arranged by the STM tip via attractive tip-molecule interaction. In this way, DyPc2 dimers of well-defined internal structure can be assembled which exist in two conformations of equivalent appearance. A binary switching between these two conformers can be induced by injecting electrons into one of the two molecules. The conformational change of the dimer proceeds via a concerted molecular rotation and minor lateral displacement. The synchronised switching observed here is attributed to steric interactions between the two molecules constituting the dimer.
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Affiliation(s)
- Yi Pan
- Paul-Drude-Institut für Festkörperelektronik, Hausvogteiplatz 5-7, 10117 Berlin, Germany
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8
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Yokoyama T, Kawasaki M, Asari T, Ohno S, Tanaka M, Yoshimoto Y. Adsorption and self-assembled structures of sexithiophene on the Si(111)-√3×√3-Ag surface. J Chem Phys 2015; 142:204701. [PMID: 26026455 DOI: 10.1063/1.4921568] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The adsorption and self-assembled structures of α-sexithiophene (α-6T) have been investigated on a Si(111)-Ag surface using scanning tunneling microscopy (STM), low-energy electron diffraction, and density functional theory calculations. The adsorbed α-6T molecules are arranged into unidirectional molecular rows with a side-by-side orientation. The molecular rows reveal three kinds of appearances in the filled-state STM images, which reflect the distinct adsorption sites. From tunneling spectroscopy, we find that the filled-state STM images of α-6T should be influenced by the surface states of Si(111)-Ag. At one monolayer coverage, sequentially ordering of the triple molecular rows results in the close-packed arrangement of the α-6T overlayer.
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Affiliation(s)
- Takashi Yokoyama
- Department of Nanoscience and Technology, Yokohama City University, 22-2 Seto, Kanazawa-ku, Yokohama 236-0027, Japan
| | - Mitsunori Kawasaki
- Department of Nanoscience and Technology, Yokohama City University, 22-2 Seto, Kanazawa-ku, Yokohama 236-0027, Japan
| | - Tomotaka Asari
- Department of Physics, Yokohama National University, 79-5 Tokiwadai, Hodogaya-ku, Yokohama 240-8501, Japan
| | - Shinya Ohno
- Department of Physics, Yokohama National University, 79-5 Tokiwadai, Hodogaya-ku, Yokohama 240-8501, Japan
| | - Masatoshi Tanaka
- Department of Physics, Yokohama National University, 79-5 Tokiwadai, Hodogaya-ku, Yokohama 240-8501, Japan
| | - Yoshihide Yoshimoto
- Department of Applied Mathematics and Physics, Tottori University, 4-101 Koyama-Minami, Tottori 680-8552, Japan
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Nacci C, Erwin SC, Kanisawa K, Fölsch S. Controlled switching within an organic molecule deliberately pinned to a semiconductor surface. ACS NANO 2012; 6:4190-4195. [PMID: 22494431 DOI: 10.1021/nn300690n] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Bistable organic molecules were deposited on a weakly binding III-V semiconductor surface and then pinned into place using individual native adatoms. These pinning atoms, positioned by atomically precise manipulation techniques in a cryogenic scanning tunneling microscope (STM) at 5 K, stabilize the π-conjugated molecule against rotation excited by the tunneling electrons. The pinning allows triggering of the molecule's intrinsic switching mechanism (a hydrogen transfer reaction) by the STM tunnel current. Density-functional theory calculations reveal that the energetics of the switching process is virtually unaffected by both the surface and the pinning atoms. Hence, we have demonstrated that individual molecules with predictable, predefined functions can be stabilized and assembled on semiconductor templates.
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Affiliation(s)
- Christophe Nacci
- Paul-Drude-Institut für Festkörperelektronik, Hausvogteiplatz 5-7, 10117 Berlin, Germany
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10
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Della Sala F, Blumstengel S, Henneberger F. Electrostatic-field-driven alignment of organic oligomers on ZnO surfaces. PHYSICAL REVIEW LETTERS 2011; 107:146401. [PMID: 22107217 DOI: 10.1103/physrevlett.107.146401] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/28/2010] [Indexed: 05/31/2023]
Abstract
We study the physisorption of organic oligomers on the strongly ionic ZnO(1010) surface by using first-principles density-functional theory and nonempirical embedding methods. It turns out that the in-plane variation of the molecule-substrate interaction energy and the bonding dipole in the vertical direction are linked up by a linear relationship originating from the electrostatic coupling of the molecule with the periodic dipolar electric field generated by the Zn-O surface dimers. Long oligomers with a highly axial π-electron system such as sexiphenyl become well oriented with alignment energies of several 100 meV along rows of a positive electric field, in full agreement with recent experiments. These findings define a new route towards the realization of highly ordered self-assembled arrays of oligomers or polymers on ZnO(1010) and similar surfaces.
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Affiliation(s)
- F Della Sala
- National Nanotechnology Laboratory, Istituto Nanoscienze-CNR, Via per Arnesano, I-73100 Lecce, Italy
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11
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Komolov AS, Akhremtchik SN, Lazneva EF. Interface doping of conjugated organic films by means of diffusion of atomic components from the surfaces of semiconductors and of metal oxides. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2011; 79:708-711. [PMID: 20863744 DOI: 10.1016/j.saa.2010.08.042] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2009] [Revised: 07/09/2010] [Accepted: 08/26/2010] [Indexed: 05/29/2023]
Abstract
The paper reports the results on the interface formation of 5-10 nm thick conjugated layers of Cu-phthalocyanine (CuPc) with a number of solid surfaces: polycrystalline Au, (SiO(2))n-Si, ZnO(0 0 0 1), Si(1 0 0), Ge(1 1 1), CdS(0 0 0 1) and GaAs(1 0 0). The results were obtained using Auger electron spectroscopy (AES) and low-energy target current electron spectroscopy (TCS). The organic overlayers were thermally deposited in situ in UHV onto substrate surfaces. The island-like organic deposits were excluded from the analysis so that only uniform organic deposits were considered. In the cases of polycrystalline Au, Si(1 0 0) and Ge(1 1 1) substrates the AES peaks of the substrate material attenuated down to the zero noise level upon the increase of the CuPc film thickness of 8-10 nm. The peaks corresponding to oxygen atoms in the case of SiO(2) substrate, and to atoms from the ZnO, GaAs and CdS substrates were clearly registered in the AES spectra of the 8-10 nm thick CuPc deposits. The relative concentration of the substrate atomic components diffused into the film was different from their relative concentration at the pure substrate surface. The concentration of the substrate dopant atoms in the CuPc film was estimated as one atom per one CuPc molecule. Using the target current electron spectroscopy, it was shown that the substrate atoms admixed in the CuPc film account for the appearance of a new peak in the density of unoccupied electronic states. Formation of intermediate TCS spectra until the CuPc deposit reaches 2-3 nm was observed in the cases of GaAs(1 0 0), ZnO(0 0 0 1), Ge(1 1 1) surfaces. The intermediate spectra show a less pronounced peak structure different from the one typical for the CuPc films. It was suggested that the intermediate layer was formed by the CuPc molecules fully or partially decomposed due to the interaction with the relatively reactive semiconductor surfaces.
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Affiliation(s)
- A S Komolov
- Physics Faculty, St. Petersburg State University, Uljanovskaja ul.1, St. Petersburg 198504, Russia.
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Zhang HL, Chen W, Chen L, Huang H, Wang XS, Yuhara J, Wee ATS. C60 molecular chains on alpha-sexithiophene nanostripes. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2007; 3:2015-8. [PMID: 17955484 DOI: 10.1002/smll.200700381] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Affiliation(s)
- Hong Liang Zhang
- Department of Physics, National University of Singapore, 2 Science Drive 3, 117542, Singapore
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13
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Mäkinen AJ, Long JP, Watkins NJ, Kafafi ZH. Sexithiophene Adlayer Growth on Vicinal Gold Surfaces. J Phys Chem B 2005; 109:5790-5. [PMID: 16851630 DOI: 10.1021/jp044921y] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We have investigated the initial stages of vacuum-deposited sexithiophene (alpha-6T) adlayer formation on Au(111) vicinal surfaces at room temperature. The in situ scanning tunneling microscopy (STM) and photoemission spectroscopy (PES) reveal a step edge-driven growth of alpha-6T on the Au(111) vicinal surfaces that first leads to the formation of an ordered monolayer, comprising two phases with the molecular major axes aligned along the step edges. The monolayer formation is then followed by the appearance of a single-phase 2D superstructure at a two-monolayer coverage. The results highlight the potential of using vicinal metal surfaces as templates for generating organized organic nanostructures over macroscopic areas for applications in organic electronics and moletronics.
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Affiliation(s)
- Antti J Mäkinen
- Naval Research Laboratory, 4555 Overlook Avenue S.W., Washington, D.C. 20375, USA.
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14
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Interface formation between Cu-phthalocyanine films and CdS and GaAs semiconductor surfaces. Colloids Surf A Physicochem Eng Asp 2004. [DOI: 10.1016/j.colsurfa.2003.12.026] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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