1
|
Zhou X, Yang S, Li Q, Bai G, Wang C, Han C. Energy level measurement for organic semiconductors. Phys Chem Chem Phys 2024; 26:2768-2779. [PMID: 38189553 DOI: 10.1039/d3cp04270g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2024]
Abstract
Along with the miniaturization and versatility of organic optoelectronic devices, it is desired to achieve a profound comprehension of the charge transport mechanism and even the basic device physics. The basis of these studies is the acquisition of relevant information about energy levels. This review provides a comprehensive analysis of five commonly-used techniques, including cyclic voltammetry, ultraviolet electron spectroscopy, inverse photoemission electron spectroscopy, low energy inverse photoemission spectroscopy and hot electron spectroscopy. According to the advantages and disadvantages, working mechanism, and application conditions, researchers will screen out a reliable and suitable characterization method, quickly and accurately. This should be beneficial for the efficient promotion of organic electronics and save valuable time for the related research studies.
Collapse
Affiliation(s)
- Xuehua Zhou
- Anhui Key Laboratory of Photoelectric-Magnetic Functional Materials, Anhui Key Laboratory of Functional Coordination Compounds, Ultra High Molecular Weight Polyethylene Fiber Engineering Research Center of Anhui Province, School of Chemistry and Chemical Engineering, Anqing Normal University, Anqing 246011, P. R. China.
| | - Shixing Yang
- Anhui Key Laboratory of Photoelectric-Magnetic Functional Materials, Anhui Key Laboratory of Functional Coordination Compounds, Ultra High Molecular Weight Polyethylene Fiber Engineering Research Center of Anhui Province, School of Chemistry and Chemical Engineering, Anqing Normal University, Anqing 246011, P. R. China.
| | - Qingxia Li
- Anhui Key Laboratory of Photoelectric-Magnetic Functional Materials, Anhui Key Laboratory of Functional Coordination Compounds, Ultra High Molecular Weight Polyethylene Fiber Engineering Research Center of Anhui Province, School of Chemistry and Chemical Engineering, Anqing Normal University, Anqing 246011, P. R. China.
| | - Guoliang Bai
- Anhui Key Laboratory of Photoelectric-Magnetic Functional Materials, Anhui Key Laboratory of Functional Coordination Compounds, Ultra High Molecular Weight Polyethylene Fiber Engineering Research Center of Anhui Province, School of Chemistry and Chemical Engineering, Anqing Normal University, Anqing 246011, P. R. China.
| | - Chunhua Wang
- Anhui Key Laboratory of Photoelectric-Magnetic Functional Materials, Anhui Key Laboratory of Functional Coordination Compounds, Ultra High Molecular Weight Polyethylene Fiber Engineering Research Center of Anhui Province, School of Chemistry and Chemical Engineering, Anqing Normal University, Anqing 246011, P. R. China.
| | - Chao Han
- The Second Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou 310000, China
- Southern Medical University, Guangzhou, 510515, China
| |
Collapse
|
2
|
Meng K, Guo L, Sun X. Strategies and applications of generating spin polarization in organic semiconductors. NANOSCALE HORIZONS 2023; 8:1132-1154. [PMID: 37424331 DOI: 10.1039/d3nh00101f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/11/2023]
Abstract
The advent of spintronics has undoubtedly revolutionized data storage, processing, and sensing applications. Organic semiconductors (OSCs), characterized by long spin relaxation times (>μs) and abundant spin-dependent properties, have emerged as promising materials for advanced spintronic applications. To successfully implement spin-related functions in organic spintronic devices, the four fundamental processes of spin generation, transport, manipulation, and detection form the main building blocks and are commonly in demand. Thereinto, the effective generation of spin polarization in OSCs is a precondition, but in practice, this has not been an easy task. In this context, considerable efforts have been made on this topic, covering novel materials systems, spin-dependent theories, and device fabrication technologies. In this review, we underline recent advances in external spin injection and organic property-induced spin polarization, according to the distinction between the sources of spin polarization. We focused mainly on summarizing and discussing both the physical mechanism and representative research on spin generation in OSCs, especially for various spin injection methods, organic magnetic materials, the chiral-induced spin selectivity effect, and the spinterface effect. Finally, the challenges and prospects that allow this topic to continue to be dynamic were outlined.
Collapse
Affiliation(s)
- Ke Meng
- Key Laboratory of Nanosystem and Hierarchical Fabrication, National Center for Nanoscience and Technology, Beijing 100190, P. R. China.
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Lidan Guo
- Key Laboratory of Nanosystem and Hierarchical Fabrication, National Center for Nanoscience and Technology, Beijing 100190, P. R. China.
| | - Xiangnan Sun
- Key Laboratory of Nanosystem and Hierarchical Fabrication, National Center for Nanoscience and Technology, Beijing 100190, P. R. China.
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, P. R. China
- School of Material Science and Engineering, Zhengzhou University, Zhengzhou 450001, P. R. China
| |
Collapse
|
3
|
Kong GD, Byeon SE, Jang J, Kim JW, Yoon HJ. Electronic Mechanism of In Situ Inversion of Rectification Polarity in Supramolecular Engineered Monolayer. J Am Chem Soc 2022; 144:7966-7971. [PMID: 35500106 DOI: 10.1021/jacs.2c02391] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
This Communication describes polarity inversion in molecular rectification and the related mechanism. Using a supramolecular engineered, ultrastable, binary-mixed self-assembled monolayer (SAM) composed of an organic molecular diode (SC11BIPY) and an inert reinforcement molecule (SC8), we probed a rectification ratio (r)-voltage relationship over an unprecedentedly wide voltage range (up to |3.5 V|) with statistical significance. We observed positive polarity in rectification at |1.0 V| (r = 107), followed by disappearance of rectification at ∼|2.25 V|, and then eventual emergence of new rectification with the opposite polarity at ∼|3.5 V| (r = 0.006; 1/r = 162). The polarity inversion occurred with a span over 4 orders of magnitude in r. Low-temperature experiments, electronic structure analysis, and theoretical calculations revealed that the unusually wide voltage range permits access to molecular orbital energy levels that are inaccessible in the traditional narrow voltage regime, inducing the unprecedented in situ inversion of polarity.
Collapse
Affiliation(s)
- Gyu Don Kong
- Department of Chemistry, Korea University, Seoul 02841, Korea
| | - Seo Eun Byeon
- Department of Chemistry, Korea University, Seoul 02841, Korea
| | - Jiung Jang
- Department of Chemistry, Korea University, Seoul 02841, Korea
| | - Jeong Won Kim
- Korea Research Institute of Standards and Science (KRISS), Daejeon 34113, Korea
| | - Hyo Jae Yoon
- Department of Chemistry, Korea University, Seoul 02841, Korea
| |
Collapse
|
4
|
Zhou X, Zhang J, Bai G, Wang C, He W, Sun X, Zhang J, Miao J. A novel energy level detector for molecular semiconductors. Phys Chem Chem Phys 2022; 24:2717-2728. [PMID: 35072681 DOI: 10.1039/d1cp01842f] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The multifunction of molecule-based devices is always achieved by improving their charge transport characteristics. These characteristics depend strongly on the energy levels of molecular semiconductors, which fundamentally govern the working principle and device performance. Therefore, an accurate measurement of these energy levels is crucial for evaluating the availability of the prepared materials and thus optimizing the device performance. Here, an easy-to-operate three-terminal hot electron transistor has been developed, which comprises a molecular optoelectronic device that records the charge transport. It achieves exceptional properties including the lowest unoccupied molecular orbit level, highest occupied molecular orbit level, higher energy states, and higher electronic bandgap. When compared with existing techniques such as cyclic voltammetry, inverse photoemission spectroscopy, and ultraviolet photoemission spectroscopy, the hot electron transistor provides in-situ characterization and categorizes the measured energy information as intrinsic properties of the molecular semiconductor. Furthermore, we provide an in-depth understanding of the fundamental device-physics, which provides promising guidance for performance optimization.
Collapse
Affiliation(s)
- Xuehua Zhou
- Anhui Province Key Laboratory of Optoelectronic and Magnetism Functional Materials, Key Laboratory of Functional Coordination Compounds of Anhui Higher Education Institutes, Anqing Normal University, Anqing 246011, P. R. China.
| | - Juansu Zhang
- Anhui Province Key Laboratory of Optoelectronic and Magnetism Functional Materials, Key Laboratory of Functional Coordination Compounds of Anhui Higher Education Institutes, Anqing Normal University, Anqing 246011, P. R. China.
| | - Guoliang Bai
- Anhui Province Key Laboratory of Optoelectronic and Magnetism Functional Materials, Key Laboratory of Functional Coordination Compounds of Anhui Higher Education Institutes, Anqing Normal University, Anqing 246011, P. R. China.
| | - Chunhua Wang
- Anhui Province Key Laboratory of Optoelectronic and Magnetism Functional Materials, Key Laboratory of Functional Coordination Compounds of Anhui Higher Education Institutes, Anqing Normal University, Anqing 246011, P. R. China.
| | - Wenxiang He
- Anhui Province Key Laboratory of Optoelectronic and Magnetism Functional Materials, Key Laboratory of Functional Coordination Compounds of Anhui Higher Education Institutes, Anqing Normal University, Anqing 246011, P. R. China.
| | - Xiangnan Sun
- Key Laboratory of Nanosystem and Hierarchical Fabrication, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing 100190, P. R. China
| | - Jianli Zhang
- State Key Laboratory of High-efficiency Utilization of Coal and Green Chemical Engineering, P. R. China
| | - Jiaojiao Miao
- School of Life Sciences, Northwestern Polytechnical University, Xi'an, Shanxi 710072, P. R. China
| |
Collapse
|
5
|
Andermann AM, Rego LGC. Energetics of the charge generation in organic donor-acceptor interfaces. J Chem Phys 2022; 156:024104. [PMID: 35032994 DOI: 10.1063/5.0076611] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Non-fullerene acceptor materials have posed new paradigms for the design of organic solar cells , whereby efficient carrier generation is obtained with small driving forces, in order to maximize the open-circuit voltage (VOC). In this paper, we use a coarse-grained mixed quantum-classical method, which combines Ehrenfest and Redfield theories, to shed light on the charge generation process in small energy offset interfaces. We have investigated the influence of the energetic driving force as well as the vibronic effects on the charge generation and photovoltaic energy conversion. By analyzing the effects of the Holstein and Peierls vibrational couplings, we find that vibrational couplings produce an overall effect of improving the charge generation. However, the two vibronic mechanisms play different roles: the Holstein relaxation mechanism decreases the charge generation, whereas the Peierls mechanism always assists the charge generation. Moreover, by examining the electron-hole binding energy as a function of time, we evince two distinct regimes for the charge separation: the temperature independent excitonic spread on a sub-100 fs timescale and the complete dissociation of the charge-transfer state that occurs on the timescale of tens to hundreds of picoseconds, depending on the temperature. The quantum dynamics of the system exhibits the three regimes of the Marcus electron transfer kinetics as the energy offset of the interface is varied.
Collapse
Affiliation(s)
- Artur M Andermann
- Department of Physics, Universidade Federal de Santa Catarina, 88040-900 Florianópolis, Santa Catarina, Brazil
| | - Luis G C Rego
- Department of Physics, Universidade Federal de Santa Catarina, 88040-900 Florianópolis, Santa Catarina, Brazil
| |
Collapse
|
6
|
Wang J, Ding T, Gao K, Wang L, Zhou P, Wu K. Marcus inverted region of charge transfer from low-dimensional semiconductor materials. Nat Commun 2021; 12:6333. [PMID: 34732730 PMCID: PMC8566515 DOI: 10.1038/s41467-021-26705-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Accepted: 10/19/2021] [Indexed: 11/18/2022] Open
Abstract
A key process underlying the application of low-dimensional, quantum-confined semiconductors in energy conversion is charge transfer from these materials, which, however, has not been fully understood yet. Extensive studies of charge transfer from colloidal quantum dots reported rates increasing monotonically with driving forces, never displaying an inverted region predicted by the Marcus theory. The inverted region is likely bypassed by an Auger-like process whereby the excessive driving force is used to excite another Coulomb-coupled charge. Herein, instead of measuring charge transfer from excitonic states (coupled electron-hole pairs), we build a unique model system using zero-dimensional quantum dots or two-dimensional nanoplatelets and surface-adsorbed molecules that allows for measuring charge transfer from transiently-populated, single-charge states. The Marcus inverted region is clearly revealed in these systems. Thus, charge transfer from excitonic and single-charge states follows the Auger-assisted and conventional Marcus charge transfer models, respectively. This knowledge should enable rational design of energetics for efficient charge extraction from low-dimensional semiconductor materials as well as suppression of the associated energy-wasting charge recombination. Marcus inverted region for charge transfer from low-dimensional semiconductor materials has been long sought after. Here, the authors reveal this region by directly measuring charge transfer from single-charge states rather than excitonic states.
Collapse
Affiliation(s)
- Junhui Wang
- State Key Laboratory of Molecular Reaction Dynamics and Dynamics Research Center for Energy and Environmental Materials, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 116023, Dalian, Liaoning, China
| | - Tao Ding
- State Key Laboratory of Molecular Reaction Dynamics and Dynamics Research Center for Energy and Environmental Materials, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 116023, Dalian, Liaoning, China
| | - Kaimin Gao
- State Key Laboratory of Molecular Reaction Dynamics and Dynamics Research Center for Energy and Environmental Materials, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 116023, Dalian, Liaoning, China.,University of the Chinese Academy of Sciences, 100049, Beijing, China
| | - Lifeng Wang
- State Key Laboratory of Molecular Reaction Dynamics and Dynamics Research Center for Energy and Environmental Materials, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 116023, Dalian, Liaoning, China.,University of the Chinese Academy of Sciences, 100049, Beijing, China
| | - Panwang Zhou
- Institute of Molecular Sciences and Engineering, Institute of Frontier and Interdisciplinary Science, Shandong University, 266235, Qingdao, Shandong, China
| | - Kaifeng Wu
- State Key Laboratory of Molecular Reaction Dynamics and Dynamics Research Center for Energy and Environmental Materials, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 116023, Dalian, Liaoning, China. .,University of the Chinese Academy of Sciences, 100049, Beijing, China.
| |
Collapse
|
7
|
Merces L, Candiotto G, Ferro LMM, de Barros A, Batista CVS, Nawaz A, Riul A, Capaz RB, Bufon CCB. Reorganization Energy upon Controlled Intermolecular Charge-Transfer Reactions in Monolithically Integrated Nanodevices. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2021; 17:e2103897. [PMID: 34596956 DOI: 10.1002/smll.202103897] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2021] [Revised: 08/29/2021] [Indexed: 06/13/2023]
Abstract
Intermolecular electron-transfer reactions are key processes in physics, chemistry, and biology. The electron-transfer rates depend primarily on the system reorganization energy, that is, the energetic cost to rearrange each reactant and its surrounding environment when a charge is transferred. Despite the evident impact of electron-transfer reactions on charge-carrier hopping, well-controlled electronic transport measurements using monolithically integrated electrochemical devices have not successfully measured the reorganization energies to this date. Here, it is shown that self-rolling nanomembrane devices with strain-engineered mechanical properties, on-a-chip monolithic integration, and multi-environment operation features can overcome this challenge. The ongoing advances in nanomembrane-origami technology allow to manufacture the nCap, a nanocapacitor platform, to perform molecular-level charge transport characterization. Thereby, employing nCap, the copper-phthalocyanine (CuPc) reorganization energy is probed, ≈0.93 eV, from temperature-dependent measurements of CuPc nanometer-thick films. Supporting the experimental findings, density functional theory calculations provide the atomistic picture of the measured CuPc charge-transfer reaction. The experimental strategy demonstrated here is a consistent route towards determining the reorganization energy of a system formed by molecules monolithically integrated into electrochemical nanodevices.
Collapse
Affiliation(s)
- Leandro Merces
- Brazilian Nanotechnology National Laboratory (LNNano), Brazilian Center for Research in Energy and Materials (CNPEM), Campinas, SP, 13083-100, Brazil
| | - Graziâni Candiotto
- Instituto de Física, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, 21941-972, Brazil
- Instituto de Química, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, 21941-909, Brazil
| | - Letícia Mariê Minatogau Ferro
- Brazilian Nanotechnology National Laboratory (LNNano), Brazilian Center for Research in Energy and Materials (CNPEM), Campinas, SP, 13083-100, Brazil
- Institute of Chemistry, University of Campinas, Campinas, SP, 13083-970, Brazil
| | - Anerise de Barros
- Institute of Chemistry, University of Campinas, Campinas, SP, 13083-970, Brazil
| | - Carlos Vinícius Santos Batista
- Brazilian Nanotechnology National Laboratory (LNNano), Brazilian Center for Research in Energy and Materials (CNPEM), Campinas, SP, 13083-100, Brazil
- Postgraduate Program in Materials Science and Technology, São Paulo State University, Bauru, SP, 17033-360, Brazil
| | - Ali Nawaz
- Center for Sensors and Devices, Bruno Kessler Foundation (FBK), Trento, 38123, Italy
| | - Antonio Riul
- Department of Applied Physics, "Gleb Wataghin" Institute of Physics, University of Campinas, Campinas, SP, 13083-859, Brazil
| | - Rodrigo B Capaz
- Brazilian Nanotechnology National Laboratory (LNNano), Brazilian Center for Research in Energy and Materials (CNPEM), Campinas, SP, 13083-100, Brazil
- Instituto de Física, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, 21941-972, Brazil
| | - Carlos César Bof Bufon
- Brazilian Nanotechnology National Laboratory (LNNano), Brazilian Center for Research in Energy and Materials (CNPEM), Campinas, SP, 13083-100, Brazil
- Institute of Chemistry, University of Campinas, Campinas, SP, 13083-970, Brazil
- Postgraduate Program in Materials Science and Technology, São Paulo State University, Bauru, SP, 17033-360, Brazil
- Mackenzie Presbyterian University, São Paulo, 01302-907, Brazil
| |
Collapse
|
8
|
Han Y, Nickle C, Maglione MS, Karuppannan SK, Casado‐Montenegro J, Qi D, Chen X, Tadich A, Cowie B, Mas‐Torrent M, Rovira C, Cornil J, Veciana J, del Barco E, Nijhuis CA. Bias-Polarity-Dependent Direct and Inverted Marcus Charge Transport Affecting Rectification in a Redox-Active Molecular Junction. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2021; 8:e2100055. [PMID: 34145786 PMCID: PMC8292891 DOI: 10.1002/advs.202100055] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Revised: 04/25/2021] [Indexed: 05/11/2023]
Abstract
This paper describes the transition from the normal to inverted Marcus region in solid-state tunnel junctions consisting of self-assembled monolayers of benzotetrathiafulvalene (BTTF), and how this transition determines the performance of a molecular diode. Temperature-dependent normalized differential conductance analyses indicate the participation of the HOMO (highest occupied molecular orbital) at large negative bias, which follows typical thermally activated hopping behavior associated with the normal Marcus regime. In contrast, hopping involving the HOMO dominates the mechanism of charge transport at positive bias, yet it is nearly activationless indicating the junction operates in the inverted Marcus region. Thus, within the same junction it is possible to switch between Marcus and inverted Marcus regimes by changing the bias polarity. Consequently, the current only decreases with decreasing temperature at negative bias when hopping is "frozen out," but not at positive bias resulting in a 30-fold increase in the molecular rectification efficiency. These results indicate that the charge transport in the inverted Marcus region is readily accessible in junctions with redox molecules in the weak coupling regime and control over different hopping regimes can be used to improve junction performance.
Collapse
Affiliation(s)
- Yingmei Han
- Department of ChemistryNational University of Singapore3 Science Drive 3Singapore117543Singapore
| | - Cameron Nickle
- Department of PhysicsUniversity of Central FloridaOrlandoFL32816USA
| | - Maria Serena Maglione
- Institut de Ciència de Materials de Barcelona (ICMAB‐CSIC)/CIBER‐BBNCampus de la UABBellaterra08193Spain
| | | | - Javier Casado‐Montenegro
- Institut de Ciència de Materials de Barcelona (ICMAB‐CSIC)/CIBER‐BBNCampus de la UABBellaterra08193Spain
| | - Dong‐Chen Qi
- Centre for Materials ScienceSchool of Chemistry and PhysicsQueensland University of TechnologyBrisbaneQueensland4001Australia
| | - Xiaoping Chen
- Department of ChemistryNational University of Singapore3 Science Drive 3Singapore117543Singapore
| | - Anton Tadich
- Australian Synchrotron ClaytonVictoria3168Australia
| | - Bruce Cowie
- Australian Synchrotron ClaytonVictoria3168Australia
| | - Marta Mas‐Torrent
- Institut de Ciència de Materials de Barcelona (ICMAB‐CSIC)/CIBER‐BBNCampus de la UABBellaterra08193Spain
| | - Concepció Rovira
- Institut de Ciència de Materials de Barcelona (ICMAB‐CSIC)/CIBER‐BBNCampus de la UABBellaterra08193Spain
| | - Jérôme Cornil
- Laboratory for Chemistry of Novel MaterialsUniversity of MonsPlace du Parc 20MonsB‐7000Belgium
| | - Jaume Veciana
- Institut de Ciència de Materials de Barcelona (ICMAB‐CSIC)/CIBER‐BBNCampus de la UABBellaterra08193Spain
| | | | - Christian A. Nijhuis
- Department of ChemistryNational University of Singapore3 Science Drive 3Singapore117543Singapore
- Centre for Advanced 2D Materials and Graphene Research CenterNational University of Singapore6 Science Drive 2Singapore117546Singapore
- Hybrid Materials for Opto‐Electronics GroupDepartment of Molecules and MaterialsMESA+ Institute for Nanotechnology and Center for Brain‐Inspired Nano SystemsFaculty of Science and TechnologyUniversity of TwenteP.O. Box 217EnschedeAE 7500The Netherlands
| |
Collapse
|
9
|
Im EJ, Jung HW, Kang YK. Evaluation of
Through‐Space
Electronic Coupling in the Cofacially Aligned
π‐Stacked
Organic
Mixed‐Valence
System. B KOREAN CHEM SOC 2021. [DOI: 10.1002/bkcs.12242] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Eun Ji Im
- Department of Chemistry Sangmyung University Seoul 03016 South Korea
| | - Hae Won Jung
- Department of Chemistry Sangmyung University Seoul 03016 South Korea
| | - Youn K. Kang
- Department of Chemistry Sangmyung University Seoul 03016 South Korea
| |
Collapse
|
10
|
Kang H, Kong GD, Yoon HJ. Solid State Dilution Controls Marcus Inverted Transport in Rectifying Molecular Junctions. J Phys Chem Lett 2021; 12:982-988. [PMID: 33464915 DOI: 10.1021/acs.jpclett.0c03251] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Traditional Marcus theory accounts for electron transfer reactions in solutions, and the polarity of solvent molecule matters for them. How such an environment polarity affects electron transfer reactions in solid-state devices, however, remains uncertain. This paper describes how the Marcus inverted charge transport is influenced by solid-state molecular dilution in large-area tunneling junctions. A monolayer of 2,2'-bipyridyl terminated n-alkanethiolate (SC11BIPY), which rectifies currents via electron hopping within the inverted regime, is diluted with n-alkanethiolate (SCn) of different lengths (n = 8, 10, or 18) or at different surface mole fractions. The dilution introduces nonpolar environments within the monolayer, hinders stabilization of charged BIPY species upon electron hopping, and pushes the equilibrium of BIPY ⇄ BIPY•- process toward the reverse direction. Our work demonstrates that solid-state molecular dilution permits systematic control of the environment polarity of active component in nanoscale devices, much like solvent polarity control in solution, and their performances.
Collapse
Affiliation(s)
- Hungu Kang
- Department of Chemistry, Korea University, Seoul, 02841, Korea
| | - Gyu Don Kong
- Department of Chemistry, Korea University, Seoul, 02841, Korea
| | - Hyo Jae Yoon
- Department of Chemistry, Korea University, Seoul, 02841, Korea
| |
Collapse
|
11
|
Takeda N, Miller JR. Inverted Region in Bimolecular Electron Transfer in Solution Enabled by Delocalization. J Am Chem Soc 2020; 142:17997-18004. [PMID: 32990434 DOI: 10.1021/jacs.0c04780] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Rate constants for bimolecular electron transfer (ET) increased with driving force, -ΔG°, reached a plateau, and then decreased in an inverted region. This rate data was described well by electron transfer theory subject to a diffusion-controlled limit. These were for ET from radical anions of polydecylthiophene (P3DT) to a series of acceptors in THF solution. When the donor was the smaller anion of quaterthiophene (T4•-) the inverted region was much less prominent and still less so for when the donor was the anion of bithiophene (T2•-). Description of the data using ET theory identifies smaller electronic couplings for the highly delocalized P3DT anions as enabling the inverted behavior: The presence of a Marcus inverted region is a consequence of delocalized electronic states. The results further imply that electronic couplings smaller than usually found for molecules in contact could boost efficiency of energy storage by electron transfer and identifies size-mismatch as an important concept in control of electronic couplings.
Collapse
Affiliation(s)
- Norihiko Takeda
- Chemistry Division, Brookhaven National Laboratory, Upton, New York 11937, United States
| | - John R Miller
- Chemistry Division, Brookhaven National Laboratory, Upton, New York 11937, United States
| |
Collapse
|
12
|
Kang H, Kong GD, Byeon SE, Yang S, Kim JW, Yoon HJ. Interplay of Fermi Level Pinning, Marcus Inverted Transport, and Orbital Gating in Molecular Tunneling Junctions. J Phys Chem Lett 2020; 11:8597-8603. [PMID: 32976711 DOI: 10.1021/acs.jpclett.0c02509] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
This Letter examines the interplay of important tunneling mechanisms-Fermi level pinning, Marcus inverted transport, and orbital gating-in a molecular rectifier. The temperature dependence of the rectifying molecular junction containing 2,2'-bipyridyl terminated n-alkanethiolate was investigated. A bell-shaped trend of activation energy as a function of applied bias evidenced the dominant occurrence of unusual Marcus inverted transport, while retention of rectification at low temperatures implied that the rectification obeyed the resonant tunneling regime. The results allowed reconciling two separately developed transport models, Marcus-Landauer energetics and Fermi level pinning-based rectification. Our work shows that the internal orbital gating can be substituted with the pinning effect, which pushes the transport mechanism into the Marcus inverted regime.
Collapse
Affiliation(s)
- Hungu Kang
- Department of Chemistry, Korea University, Seoul 02841, Korea
| | - Gyu Don Kong
- Department of Chemistry, Korea University, Seoul 02841, Korea
| | - Seo Eun Byeon
- Department of Chemistry, Korea University, Seoul 02841, Korea
| | - Sena Yang
- Korea Research Institute of Standards and Science (KRISS), Daejeon 34113, Korea
| | - Jeong Won Kim
- Korea Research Institute of Standards and Science (KRISS), Daejeon 34113, Korea
| | - Hyo Jae Yoon
- Department of Chemistry, Korea University, Seoul 02841, Korea
| |
Collapse
|
13
|
Ran X, Hou P, Song J, Song H, Zhong X, Wang J. Negative differential resistance effect in resistive switching devices based on h-LuFeO 3/CoFe 2O 4 heterojunctions. Phys Chem Chem Phys 2020; 22:5819-5825. [PMID: 32107521 DOI: 10.1039/d0cp00530d] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The negative differential resistance (NDR) effect enables multilevel storage and gradual resistance modulation in resistive switching (RS) devices to be achieved. However, the poor reproducibility of NDR is the obstacle that restricts their application because the appearance of the NDR effect in RS devices is usually accidental or unstable at room temperature. In this report, we demonstrate a polarization and interfacial defect modulated NDR effect in h-LuFeO3/CoFe2O4 heterojunction-based RS devices; especially, the NDR is reproducible after hundreds of cycles at room temperature. This research provides an effective way for realizing the reproducible NDR effect in ferroelectric RS devices, and it may promote the development and application of RS devices with the NDR effect.
Collapse
Affiliation(s)
- Xinxin Ran
- School of Materials Science and Engineering, Xiangtan University, Xiangtan 411105, Hunan, China.
| | - Pengfei Hou
- School of Materials Science and Engineering, Xiangtan University, Xiangtan 411105, Hunan, China. and Science and Technology on Reliability Physics and Application Technology of Electronic Component Laboratory, Guangzhou 510610, Guangdong, China
| | - Jiaxun Song
- School of Materials Science and Engineering, Xiangtan University, Xiangtan 411105, Hunan, China.
| | - Hongjia Song
- School of Materials Science and Engineering, Xiangtan University, Xiangtan 411105, Hunan, China.
| | - Xiangli Zhong
- School of Materials Science and Engineering, Xiangtan University, Xiangtan 411105, Hunan, China.
| | - Jinbin Wang
- School of Materials Science and Engineering, Xiangtan University, Xiangtan 411105, Hunan, China.
| |
Collapse
|
14
|
Zhong Y, Causa' M, Moore GJ, Krauspe P, Xiao B, Günther F, Kublitski J, Shivhare R, Benduhn J, BarOr E, Mukherjee S, Yallum KM, Réhault J, Mannsfeld SCB, Neher D, Richter LJ, DeLongchamp DM, Ortmann F, Vandewal K, Zhou E, Banerji N. Sub-picosecond charge-transfer at near-zero driving force in polymer:non-fullerene acceptor blends and bilayers. Nat Commun 2020; 11:833. [PMID: 32047157 PMCID: PMC7012859 DOI: 10.1038/s41467-020-14549-w] [Citation(s) in RCA: 87] [Impact Index Per Article: 21.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2019] [Accepted: 01/18/2020] [Indexed: 12/03/2022] Open
Abstract
Organic photovoltaics based on non-fullerene acceptors (NFAs) show record efficiency of 16 to 17% and increased photovoltage owing to the low driving force for interfacial charge-transfer. However, the low driving force potentially slows down charge generation, leading to a tradeoff between voltage and current. Here, we disentangle the intrinsic charge-transfer rates from morphology-dependent exciton diffusion for a series of polymer:NFA systems. Moreover, we establish the influence of the interfacial energetics on the electron and hole transfer rates separately. We demonstrate that charge-transfer timescales remain at a few hundred femtoseconds even at near-zero driving force, which is consistent with the rates predicted by Marcus theory in the normal region, at moderate electronic coupling and at low re-organization energy. Thus, in the design of highly efficient devices, the energy offset at the donor:acceptor interface can be minimized without jeopardizing the charge-transfer rate and without concerns about a current-voltage tradeoff. It has been commonly believed that the driving force at the donor-acceptor heterojunction is vital to efficient charge separation in organic solar cells. Here Zhong et al. show that the driving force can be as small as 0.05 eV without compromising the charge transfer rate and efficiency.
Collapse
Affiliation(s)
- Yufei Zhong
- Department of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, CH-3012, Bern, Switzerland
| | - Martina Causa'
- Department of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, CH-3012, Bern, Switzerland
| | - Gareth John Moore
- Department of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, CH-3012, Bern, Switzerland
| | - Philipp Krauspe
- Department of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, CH-3012, Bern, Switzerland
| | - Bo Xiao
- Chinese Academy of Sciences (CAS) Key Laboratory of Nanosystem and Hierarchical Fabrication, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing, 100190, P. R. China
| | - Florian Günther
- Instituto de Física de São Carlos (IFSC), Universidade de São Paulo (USP), Av. Trabalhador saocarlense, 400, CEP, 13560-970, São Carlos, Brazil
| | - Jonas Kublitski
- Dresden Integrated Center for Applied Physics and Photonic Materials (IAPP) and Institute for Applied Physics Technische Universität Dresden, Nöthnitzer Str. 61, 01187, Dresden, Germany
| | - Rishi Shivhare
- Dresden Integrated Center for Applied Physics and Photonic Materials (IAPP) and Institute for Applied Physics Technische Universität Dresden, Nöthnitzer Str. 61, 01187, Dresden, Germany
| | - Johannes Benduhn
- Dresden Integrated Center for Applied Physics and Photonic Materials (IAPP) and Institute for Applied Physics Technische Universität Dresden, Nöthnitzer Str. 61, 01187, Dresden, Germany
| | - Eyal BarOr
- Institute of Physics and Astronomy, University of Potsdam, Karl-Liebknecht-Str. 24-25, 14476, Potsdam-Golm, Germany
| | - Subhrangsu Mukherjee
- Material Measurement Laboratory, National Institute of Standards and Technology (NIST), Gaithersburg, MD, 20899, USA
| | - Kaila M Yallum
- Department of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, CH-3012, Bern, Switzerland
| | - Julien Réhault
- Department of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, CH-3012, Bern, Switzerland
| | - Stefan C B Mannsfeld
- Dresden Integrated Center for Applied Physics and Photonic Materials (IAPP) and Institute for Applied Physics Technische Universität Dresden, Nöthnitzer Str. 61, 01187, Dresden, Germany
| | - Dieter Neher
- Institute of Physics and Astronomy, University of Potsdam, Karl-Liebknecht-Str. 24-25, 14476, Potsdam-Golm, Germany
| | - Lee J Richter
- Material Measurement Laboratory, National Institute of Standards and Technology (NIST), Gaithersburg, MD, 20899, USA
| | - Dean M DeLongchamp
- Material Measurement Laboratory, National Institute of Standards and Technology (NIST), Gaithersburg, MD, 20899, USA
| | - Frank Ortmann
- Center for Advancing Electronics Dresden, Technische Universität Dresden, Helmholtzstr. 18, 01062, Dresden, Germany
| | - Koen Vandewal
- Institute for Materials Research (IMO-IMOMEC), Hasselt University, Wetenschapspark 1, 3590, Diepenbeek, Belgium
| | - Erjun Zhou
- Chinese Academy of Sciences (CAS) Key Laboratory of Nanosystem and Hierarchical Fabrication, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing, 100190, P. R. China.
| | - Natalie Banerji
- Department of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, CH-3012, Bern, Switzerland.
| |
Collapse
|
15
|
Jung HW, Yoon SE, Carroll PJ, Gau MR, Therien MJ, Kang YK. Distance Dependence of Electronic Coupling in Rigid, Cofacially Compressed, π-Stacked Organic Mixed-Valence Systems. J Phys Chem B 2020; 124:1033-1048. [DOI: 10.1021/acs.jpcb.9b09578] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Hae Won Jung
- Department of Chemistry, Sangmyung University, Seoul 03016, Korea
| | - Sung Ewn Yoon
- Department of Chemistry, Sangmyung University, Seoul 03016, Korea
| | - Patrick J. Carroll
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Michael R. Gau
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Michael J. Therien
- Department of Chemistry, Duke University, Durham, North Carolina 27708, United States
| | - Youn K. Kang
- Department of Chemistry, Sangmyung University, Seoul 03016, Korea
| |
Collapse
|