1
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Yagi T, Yoshida K, Sakurai S, Kawai T, Nonoguchi Y. Semiconducting Carbon Nanotube Extraction Enabled by Alkylated Cellulose Wrapping. J Am Chem Soc 2024. [PMID: 38934730 DOI: 10.1021/jacs.4c05468] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/28/2024]
Abstract
With the growing demand for postsilicon electronics, the purification of single-walled carbon nanotubes (SWCNTs) in terms of their chirality, which defines their atomic and electronic structure, is becoming increasingly important. Herein, we demonstrate the selective extraction of high-quality semiconducting SWCNTs using alkyl cellulose as a dispersant in organic solvents. We investigated the separation factors of dispersant structures, such as the degree of substitution (DS) and molecular weight, and clarified the appropriate dispersant structures, such as moderately substituted hexyl cellulose, for selective semiconducting SWCNT extraction. Due to the improved purity and quality of the semiconducting SWCNTs obtained by this method, their films exhibit excellent thermoelectric power factors, outperforming not only unsorted SWCNTs but also conducting polymer-sorted SWCNTs. This sorting technology paves the way for supplying high-quality semiconducting SWCNTs in a viable manner.
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Affiliation(s)
- Tomoko Yagi
- Division of Materials Science, Nara Institute of Science and Technology, Ikoma 630-0192, Japan
| | - Kazuhiro Yoshida
- Faculty of Materials Science and Engineering, Kyoto Institute of Technology, Kyoto 606-8585, Japan
| | - Shunsuke Sakurai
- Nano Carbon Device Research Center, National Institute of Advanced Industrial Science and Technology, Tsukuba 305-8565, Japan
| | - Tsuyoshi Kawai
- Division of Materials Science, Nara Institute of Science and Technology, Ikoma 630-0192, Japan
| | - Yoshiyuki Nonoguchi
- Division of Materials Science, Nara Institute of Science and Technology, Ikoma 630-0192, Japan
- Faculty of Materials Science and Engineering, Kyoto Institute of Technology, Kyoto 606-8585, Japan
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2
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Myers A, Li Z, Gish MK, Earley JD, Johnson JC, Hermosilla-Palacios MA, Blackburn JL. Ultrafast Charge Transfer Cascade in a Mixed-Dimensionality Nanoscale Trilayer. ACS NANO 2024; 18:8190-8198. [PMID: 38465641 PMCID: PMC10958597 DOI: 10.1021/acsnano.3c12179] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2023] [Revised: 02/23/2024] [Accepted: 03/05/2024] [Indexed: 03/12/2024]
Abstract
Innovation in optoelectronic semiconductor devices is driven by a fundamental understanding of how to move charges and/or excitons (electron-hole pairs) in specified directions for doing useful work, e.g., for making fuels or electricity. The diverse and tunable electronic and optical properties of two-dimensional (2D) transition metal dichalcogenides (TMDCs) and one-dimensional (1D) semiconducting single-walled carbon nanotubes (s-SWCNTs) make them good quantum confined model systems for fundamental studies of charge and exciton transfer across heterointerfaces. Here we demonstrate a mixed-dimensionality 2D/1D/2D MoS2/SWCNT/WSe2 heterotrilayer that enables ultrafast photoinduced exciton dissociation, followed by charge diffusion and slow recombination. Importantly, the heterotrilayer serves to double charge carrier yield relative to a MoS2/SWCNT heterobilayer and also demonstrates the ability of the separated charges to overcome interlayer exciton binding energies to diffuse from one TMDC/SWCNT interface to the other 2D/1D interface, resulting in Coulombically unbound charges. Interestingly, the heterotrilayer also appears to enable efficient hole transfer from SWCNTs to WSe2, which is not observed in the identically prepared WSe2/SWCNT heterobilayer, suggesting that increasing the complexity of nanoscale trilayers may modify dynamic pathways. Our work suggests "mixed-dimensionality" TMDC/SWCNT based heterotrilayers as both interesting model systems for mechanistic studies of carrier dynamics at nanoscale heterointerfaces and for potential applications in advanced optoelectronic systems.
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Affiliation(s)
- Alexis
R. Myers
- National
Renewable Energy Laboratory, Golden, Colorado 80401, United States
- Department
of Chemistry, University of Colorado−Boulder, Boulder, Colorado 80309, United States
| | - Zhaodong Li
- National
Renewable Energy Laboratory, Golden, Colorado 80401, United States
- The
Institute of Technological Sciences, Wuhan
University, Wuhan, Hubei 430072, China
| | - Melissa K. Gish
- National
Renewable Energy Laboratory, Golden, Colorado 80401, United States
| | - Justin D. Earley
- National
Renewable Energy Laboratory, Golden, Colorado 80401, United States
- Department
of Chemistry, University of Colorado−Boulder, Boulder, Colorado 80309, United States
| | - Justin C. Johnson
- National
Renewable Energy Laboratory, Golden, Colorado 80401, United States
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3
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Hermosilla-Palacios MA, Martinez M, Doud EA, Hertel T, Spokoyny AM, Cambré S, Wenseleers W, Kim YH, Ferguson AJ, Blackburn JL. Carrier density and delocalization signatures in doped carbon nanotubes from quantitative magnetic resonance. NANOSCALE HORIZONS 2024; 9:278-284. [PMID: 38044846 DOI: 10.1039/d3nh00480e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/05/2023]
Abstract
High-performance semiconductor materials and devices are needed to supply the growing energy and computing demand. Organic semiconductors (OSCs) are attractive options for opto-electronic devices, due to their low cost, extensive tunability, easy fabrication, and flexibility. Semiconducting single-walled carbon nanotubes (s-SWCNTs) have been extensively studied due to their high carrier mobility, stability and opto-electronic tunability. Although molecular charge transfer doping affords widely tunable carrier density and conductivity in s-SWCNTs (and OSCs in general), a pervasive challenge for such systems is reliable measurement of charge carrier density and mobility. In this work we demonstrate a direct quantification of charge carrier density, and by extension carrier mobility, in chemically doped s-SWCNTs by a nuclear magnetic resonance approach. The experimental results are verified by a phase-space filling doping model, and we suggest this approach should be broadly applicable for OSCs. Our results show that hole mobility in doped s-SWCNT networks increases with increasing charge carrier density, a finding that is contrary to that expected for mobility limited by ionized impurity scattering. We discuss the implications of this important finding for additional tunability and applicability of s-SWCNT and OSC devices.
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Affiliation(s)
| | - Marissa Martinez
- National Renewable Energy Laboratory, Golden, Colorado 80401, USA.
| | - Evan A Doud
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095, USA
| | - Tobias Hertel
- Institute of Physical and Theoretical Chemistry, Julius-Maximilian, University Würzburg, 97074, Würzburg, Germany
| | - Alexander M Spokoyny
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095, USA
| | - Sofie Cambré
- Department of Physics, University of Antwerp, Antwerp 2610, Belgium
| | - Wim Wenseleers
- Department of Physics, University of Antwerp, Antwerp 2610, Belgium
| | - Yong-Hyun Kim
- Department of Physics, Korea Advanced Institute of Science and Technology, Daejeon 34141, Republic of Korea
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4
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Liu Y, Zhao Z, Kang L, Qiu S, Li Q. Molecular Doping Modulation and Applications of Structure-Sorted Single-Walled Carbon Nanotubes: A Review. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2024; 20:e2304075. [PMID: 37675833 DOI: 10.1002/smll.202304075] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Revised: 07/26/2023] [Indexed: 09/08/2023]
Abstract
Single-walled carbon nanotubes (SWCNTs) that have a reproducible distribution of chiralities or single chirality are among the most competitive materials for realizing post-silicon electronics. Molecular doping, with its non-destructive and fine-tunable characteristics, is emerging as the primary doping approach for the structure-controlled SWCNTs, enabling their eventual use in various functional devices. This review provides an overview of important advances in the area of molecular doping of structure-controlled SWCNTs and their applications. The first part introduces the underlying physical process of molecular doping, followed by a comprehensive survey of the commonly used dopants for SWCNTs to date. Then, it highlights how the convergence of molecular doping and structure-sorting strategies leads to significantly improved functionality of SWCNT-based field-effect transistor arrays, transparent electrodes in optoelectronics, thermoelectrics, and many emerging devices. At last, several challenges and opportunities in this field are discussed, with the hope of shedding light on promoting the practical application of SWCNTs in future electronics.
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Affiliation(s)
- Ye Liu
- Key Laboratory of Multifunctional Nanomaterials and Smart Systems, Division of Advanced Materials, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, Suzhou, 215123, China
| | - Zhigang Zhao
- Key Laboratory of Multifunctional Nanomaterials and Smart Systems, Division of Advanced Materials, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, Suzhou, 215123, China
| | - Lixing Kang
- Key Laboratory of Multifunctional Nanomaterials and Smart Systems, Division of Advanced Materials, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, Suzhou, 215123, China
| | - Song Qiu
- Key Laboratory of Multifunctional Nanomaterials and Smart Systems, Division of Advanced Materials, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, Suzhou, 215123, China
| | - Qingwen Li
- Key Laboratory of Multifunctional Nanomaterials and Smart Systems, Division of Advanced Materials, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, Suzhou, 215123, China
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5
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Ahn S, Zor C, Yang S, Lagnoni M, Dewar D, Nimmo T, Chau C, Jenkins M, Kibler AJ, Pateman A, Rees GJ, Gao X, Adamson P, Grobert N, Bertei A, Johnson LR, Bruce PG. Why charging Li-air batteries with current low-voltage mediators is slow and singlet oxygen does not explain degradation. Nat Chem 2023:10.1038/s41557-023-01203-3. [PMID: 37264102 DOI: 10.1038/s41557-023-01203-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Accepted: 04/14/2023] [Indexed: 06/03/2023]
Abstract
Although Li-air rechargeable batteries offer higher energy densities than lithium-ion batteries, the insulating Li2O2 formed during discharge hinders rapid, efficient re-charging. Redox mediators are used to facilitate Li2O2 oxidation; however, fast kinetics at a low charging voltage are necessary for practical applications and are yet to be achieved. We investigate the mechanism of Li2O2 oxidation by redox mediators. The rate-limiting step is the outer-sphere one-electron oxidation of Li2O2 to LiO2, which follows Marcus theory. The second step is dominated by LiO2 disproportionation, forming mostly triplet-state O2. The yield of singlet-state O2 depends on the redox potential of the mediator in a way that does not correlate with electrolyte degradation, in contrast to earlier views. Our mechanistic understanding explains why current low-voltage mediators (<+3.3 V) fail to deliver high rates (the maximum rate is at +3.74 V) and suggests important mediator design strategies to deliver sufficiently high rates for fast charging at potentials closer to the thermodynamic potential of Li2O2 oxidation (+2.96 V).
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Affiliation(s)
- Sunyhik Ahn
- Department of Materials, University of Oxford, Oxford, UK
| | - Ceren Zor
- Department of Materials, University of Oxford, Oxford, UK
| | - Sixie Yang
- Department of Materials, University of Oxford, Oxford, UK
| | - Marco Lagnoni
- Department of Civil and Industrial Engineering, University of Pisa, Pisa, Italy
| | - Daniel Dewar
- Department of Materials, University of Oxford, Oxford, UK
| | - Tammy Nimmo
- Department of Materials, University of Oxford, Oxford, UK
| | - Chloe Chau
- Department of Materials, University of Oxford, Oxford, UK
| | - Max Jenkins
- Department of Materials, University of Oxford, Oxford, UK
| | - Alexander J Kibler
- Nottingham Applied Materials and Interfaces Group, School of Chemistry, University of Nottingham, Nottingham, UK
| | | | - Gregory J Rees
- Department of Materials, University of Oxford, Oxford, UK
| | - Xiangwen Gao
- Department of Materials, University of Oxford, Oxford, UK
| | - Paul Adamson
- Department of Materials, University of Oxford, Oxford, UK
| | - Nicole Grobert
- Department of Materials, University of Oxford, Oxford, UK
| | - Antonio Bertei
- Department of Civil and Industrial Engineering, University of Pisa, Pisa, Italy
| | - Lee R Johnson
- Nottingham Applied Materials and Interfaces Group, School of Chemistry, University of Nottingham, Nottingham, UK
| | - Peter G Bruce
- Department of Materials, University of Oxford, Oxford, UK.
- Department of Chemistry, University of Oxford, Oxford, UK.
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6
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Wieland L, Li H, Zhang X, Chen J, Flavel BS. Ternary PM6:Y6 Solar Cells with Single‐Walled Carbon Nanotubes. SMALL SCIENCE 2022. [DOI: 10.1002/smsc.202200079] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Affiliation(s)
- Laura Wieland
- Institute of Nanotechnology Karlsruhe Institute of Technology Hermann-von-Helmholtz-Platz 1 76344 Eggenstein-Leopoldshafen Germany
- Institute of Materials Science Technische Universität Darmstadt Alarich-Weiss-Straße 2 Darmstadt 64287 Germany
| | - Han Li
- Institute of Nanotechnology Karlsruhe Institute of Technology Hermann-von-Helmholtz-Platz 1 76344 Eggenstein-Leopoldshafen Germany
| | - Xuning Zhang
- Key Laboratory of Optic-Electronic Information and Materials of Hebei Province College of Physics Science and Technology Hebei University Baoding 071002 China
| | - Jianhui Chen
- Key Laboratory of Optic-Electronic Information and Materials of Hebei Province College of Physics Science and Technology Hebei University Baoding 071002 China
| | - Benjamin S. Flavel
- Institute of Nanotechnology Karlsruhe Institute of Technology Hermann-von-Helmholtz-Platz 1 76344 Eggenstein-Leopoldshafen Germany
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7
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Energy funneling and charge separation in CdS modified with dual cocatalysts for enhanced H2 generation. CHINESE JOURNAL OF CATALYSIS 2022. [DOI: 10.1016/s1872-2067(21)64009-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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8
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Carr JM, Allen TG, Larson BW, Davydenko IG, Dasari RR, Barlow S, Marder SR, Reid OG, Rumbles G. Short and long-range electron transfer compete to determine free-charge yield in organic semiconductors. MATERIALS HORIZONS 2022; 9:312-324. [PMID: 34787147 DOI: 10.1039/d1mh01331a] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Understanding how Frenkel excitons efficiently split to form free-charges in low-dielectric constant organic semiconductors has proven challenging, with many different models proposed in recent years to explain this phenomenon. Here, we present evidence that a simple model invoking a modest amount of charge delocalization, a sum over the available microstates, and the Marcus rate constant for electron transfer can explain many seemingly contradictory phenomena reported in the literature. We use an electron-accepting fullerene host matrix dilutely sensitized with a series of electron donor molecules to test this hypothesis. The donor series enables us to tune the driving force for photoinduced electron transfer over a range of 0.7 eV, mapping out normal, optimal, and inverted regimes for free-charge generation efficiency, as measured by time-resolved microwave conductivity. However, the photoluminescence of the donor is rapidly quenched as the driving force increases, with no evidence for inverted behavior, nor the linear relationship between photoluminescence quenching and charge-generation efficiency one would expect in the absence of additional competing loss pathways. This behavior is self-consistently explained by competitive formation of bound charge-transfer states and long-range or delocalized free-charge states, where both rate constants are described by the Marcus rate equation. Moreover, the model predicts a suppression of the inverted regime for high-concentration blends and efficient ultrafast free-charge generation, providing a mechanistic explanation for why Marcus-inverted-behavior is rarely observed in device studies.
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Affiliation(s)
- Joshua M Carr
- University of Colorado Boulder, Materials Science & Engineering Program, Boulder, CO, 80303, USA
| | - Taylor G Allen
- National Renewable Energy Laboratory, Chemistry and Nanoscience Center, Golden, CO, 80401, USA.
| | - Bryon W Larson
- National Renewable Energy Laboratory, Chemistry and Nanoscience Center, Golden, CO, 80401, USA.
| | - Iryna G Davydenko
- Georgia Institute of Technology, School of Chemistry and Biochemistry, Atlanta, GA, 30332, USA
| | - Raghunath R Dasari
- Georgia Institute of Technology, School of Chemistry and Biochemistry, Atlanta, GA, 30332, USA
| | - Stephen Barlow
- National Renewable Energy Laboratory, Chemistry and Nanoscience Center, Golden, CO, 80401, USA.
- Georgia Institute of Technology, School of Chemistry and Biochemistry, Atlanta, GA, 30332, USA
- University of Colorado Boulder, Renewable and Sustainable Energy Institute, Boulder, CO, 80303, USA
| | - Seth R Marder
- National Renewable Energy Laboratory, Chemistry and Nanoscience Center, Golden, CO, 80401, USA.
- Georgia Institute of Technology, School of Chemistry and Biochemistry, Atlanta, GA, 30332, USA
- University of Colorado Boulder, Renewable and Sustainable Energy Institute, Boulder, CO, 80303, USA
- University of Colorado Boulder, Department of Chemistry, Boulder, CO, 80303, USA
- University of Colorado Boulder, Department of Chemical and Biological Engineering, Boulder, CO, 80303, USA
| | - Obadiah G Reid
- National Renewable Energy Laboratory, Chemistry and Nanoscience Center, Golden, CO, 80401, USA.
- University of Colorado Boulder, Renewable and Sustainable Energy Institute, Boulder, CO, 80303, USA
| | - Garry Rumbles
- National Renewable Energy Laboratory, Chemistry and Nanoscience Center, Golden, CO, 80401, USA.
- University of Colorado Boulder, Renewable and Sustainable Energy Institute, Boulder, CO, 80303, USA
- University of Colorado Boulder, Department of Chemistry, Boulder, CO, 80303, USA
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9
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Powell D, Hansen KR, Flannery L, Whittaker-Brooks L. Traversing Excitonic and Ionic Landscapes: Reduced-Dimensionality-Inspired Design of Organometal Halide Semiconductors for Energy Applications. Acc Chem Res 2021; 54:4371-4382. [PMID: 34841870 DOI: 10.1021/acs.accounts.1c00492] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
At the very heart of the global semiconductor industry lies the omnipresent push for new materials discovery. New materials constantly rise and fall out of fashion in the scientific literature, with those passing an initial phase of research scrutiny becoming hotbeds of characterization and optimization efforts. Yet, innumerable hours of painstaking research have been devoted to materials that have ultimately fallen by the wayside after crossing over an indefinable threshold, whereupon historical optimism is met with newfound skepticism. Materials have to perform well, and they have to do it quickly. In the past decade, metal-halide perovskites (MHPs) have garnered widespread attention. The hegemonic view in both academic and industrial circles is that these materials could be engineered to meet the demands of the semiconductor industry. Their promise as inexpensive solar cell devices is highly attractive, and it has been nothing short of remarkable that efficiencies have risen from 3.8% in 2009 to more than 25.5% in 2021. Moreover, MHPs are poised to be revolutionary materials in more ways than one. The highest MHP LED efficiency was recently reported (23.4%), and MHPs have demonstrated promise in photodetectors, memristors, and transistors. However, the many excellent properties of MHPs are contrasted by longstanding stability and reproducibility limitations that have hindered their commercialization. Overcoming the limitations of MHPs is ultimately a materials engineering problem, which should be solved by mapping more precise relationships between structure, composition, and device performance. In 1958, Francis Crick famously developed the central dogma of molecular biology which describes the unidirectional flow of information in biological systems. In the words of Crick, "nature has devised a unique instrument in which an underlying simplicity is used to express great subtlety and versatility." In this Account, taking inspiration from the hierarchical organization of nature, we describe a hierarchical approach to materials engineering of organic metal-halide semiconductors. We demonstrate that organo-metal halide semiconductors' dimensionality, composition, and morphology dictate their optoelectronic properties and can be exploited in defining more explicit relationships between structure and function. Here, we traverse three-dimensional (3D), two-dimensional (2D), and one-dimensional (1D) organo-metal halide semiconductors, detailing the morphological and compositional differences in each and the implications that can be drawn within each domain on the engineering process. Control over ion migration pathways via morphology engineering as well as control over charge formation in organic-inorganic semiconductors is demonstrated. Fundamental insights into the amount of static and dynamic disorder in the MHP lattice are provided, which can be continuously tuned as a function of composition and morphology. Using electroabsorption spectroscopy on 2D MHPs, a disorder-induced dipole moment in the exciton proportional to the summed value of static and dynamic disorder is measured. Spectroscopic isolation of exciton features in 2D MHP electroabsorption spectra allows us to obtain precise, model-independent measurements of exciton binding energies to study the effect of chemical substitutions, such as Sn2+ → Pb2+, on the value of the exciton binding energy. Finally, we conclude that this multidimensional platform, with the aid of machine learning and robotics, will be foundational in accurately predicting structure-property-device relationships in organo-metal halide semiconductors in the future.
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Affiliation(s)
- Daniel Powell
- Department of Chemistry, University of Utah, Salt Lake City, Utah 84112, United States
| | - Kameron R. Hansen
- Department of Chemistry, University of Utah, Salt Lake City, Utah 84112, United States
| | - Laura Flannery
- Department of Chemistry, University of Utah, Salt Lake City, Utah 84112, United States
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10
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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.
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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.
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11
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Kang HS, Peurifoy S, Zhang B, Ferguson AJ, Reid OG, Nuckolls C, Blackburn JL. Linking optical spectra to free charges in donor/acceptor heterojunctions: cross-correlation of transient microwave and optical spectroscopy. MATERIALS HORIZONS 2021; 8:1509-1517. [PMID: 34846459 DOI: 10.1039/d0mh01810d] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
The primary photoexcited species in excitonic semiconductors is a bound electron-hole pair, or exciton. An important strategy for producing separated electrons and holes in photoexcited excitonic semiconductors is the use of donor/acceptor heterojunctions, but the degree to which the carriers can escape their mutual Coulomb attraction is still debated for many systems. Here, we employ a combined pump-probe ultrafast transient absorption (TA) spectroscopy and time-resolved microwave conductivity (TRMC) study on a suite of model excitonic heterojunctions consisting of mono-chiral semiconducting single-walled carbon nanotube (s-SWCNT) electron donors and small-molecule electron acceptors. Comparison of the charge-separated state dynamics between TA and TRMC photoconductance reveals a quantitative match over the 0.5 microsecond time scale. Charge separation yields derived from TA allow extraction of s-SWCNT hole mobilities of ca. 1.5 cm2 V-1 s-1 (at 9 GHz) by TRMC. The correlation between the techniques conclusively demonstrates that photoinduced charge carriers separated across these heterojunctions do not form bound charge transfer states, but instead form free/mobile charge carriers.
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Affiliation(s)
- Hyun Suk Kang
- National Renewable Energy Laboratory, Golden, CO 80401, USA.
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12
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Menezes S, Samantilleke AP, Larson BW. Quantized electronic transitions in electrodeposited copper indium selenide nanocrystalline homojunctions. Sci Rep 2021; 11:3957. [PMID: 33597598 PMCID: PMC7889914 DOI: 10.1038/s41598-021-83526-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Accepted: 01/25/2021] [Indexed: 11/16/2022] Open
Abstract
Pairing semiconductors with electrochemical processing offers an untapped opportunity to create novel nanostructures for practical devices. Here we report the results of one such pairing: the in-situ formation of highly-doped, interface-matched, sharp nanocrystalline homojunctions (NHJs) with single step electrodeposition of two copper-indium-selenide (CISe) compounds on flexible foil. It produces a homogenous film, comprising inherently ordered, 3-dimensional interconnected network of pn-CISe NHJs. These CISe NHJs exhibit surprising non-linear emissions, quantized transitions, large carrier mobility, low trap-state-density, long carrier lifetime and possible up-conversion. They facilitate efficient separation of minority carriers, reduce recombination and essentially function like quantum materials. This approach mitigates the material issues and complex fabrication of incumbent nanoscale heterojunctions; it also overcomes the flexibility and scale-up challenges of conventional planar pn junctions. The self-stabilized CISe NHJ film can be roll-to-roll processed in ambient atmosphere, thus providing a promising platform for a range of optoelectronic technologies. This concept exemplified by CISe compounds can be adapted to create nano-scale pn junctions with other inorganic semiconductors.
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13
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Deng HH, Huang KY, Zhu CT, Shen JF, Zhang XP, Peng HP, Xia XH, Chen W. Bell-Shaped Electron Transfer Kinetics in Gold Nanoclusters. J Phys Chem Lett 2021; 12:876-883. [PMID: 33428405 DOI: 10.1021/acs.jpclett.0c03617] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Although metal nanoclusters (MNCs) have shown great promise for the further development of photochemical techniques to be applied in diverse areas (e.g., photoelectronic devices, photochemical sensors, photocatalysts, and energy storage and conversion systems), the fundamental problem of their electron transfer behavior still remains unsolved. Herein, a driving force-dependent photoinduced electron transfer process of gold nanoclusters (AuNCs) is clarified for the first time from a rational-designed opposite-charged system. It was found that the electron transfer dynamic of carboxylated chitosan and dithiothreitol-commodified AuNCs (CC/DTT-AuNCs) can be satisfactorily described by the Marcus electron transfer theory. This proved model was applied to estimate the ultrafast charge separation process between CC/DTT-AuNCs and mitoxantrone, which was confirmed by fluorescence quenching and femtosecond transient absorption spectroscopy measurements. We envision that this work will open a new door for understanding the electron transfer behavior of MNCs and facilitate the design of advanced optoelectronic devices.
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Affiliation(s)
- Hao-Hua Deng
- Higher Educational Key Laboratory for Nano Biomedical Technology of Fujian Province, Department of Pharmaceutical Analysis, Fujian Medical University, Fuzhou 350004, China
| | - Kai-Yuan Huang
- Higher Educational Key Laboratory for Nano Biomedical Technology of Fujian Province, Department of Pharmaceutical Analysis, Fujian Medical University, Fuzhou 350004, China
| | - Chen-Ting Zhu
- Higher Educational Key Laboratory for Nano Biomedical Technology of Fujian Province, Department of Pharmaceutical Analysis, Fujian Medical University, Fuzhou 350004, China
| | - Jian-Feng Shen
- Higher Educational Key Laboratory for Nano Biomedical Technology of Fujian Province, Department of Pharmaceutical Analysis, Fujian Medical University, Fuzhou 350004, China
| | - Xiang-Ping Zhang
- Higher Educational Key Laboratory for Nano Biomedical Technology of Fujian Province, Department of Pharmaceutical Analysis, Fujian Medical University, Fuzhou 350004, China
| | - Hua-Ping Peng
- Higher Educational Key Laboratory for Nano Biomedical Technology of Fujian Province, Department of Pharmaceutical Analysis, Fujian Medical University, Fuzhou 350004, China
| | - Xing-Hua Xia
- State Key Laboratory of Analytical Chemistry for Life Science and Collaborative Innovation Center of Chemistry for Life Sciences, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, China
| | - Wei Chen
- Higher Educational Key Laboratory for Nano Biomedical Technology of Fujian Province, Department of Pharmaceutical Analysis, Fujian Medical University, Fuzhou 350004, China
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14
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Zhang M, Zhu L, Zhou G, Hao T, Qiu C, Zhao Z, Hu Q, Larson BW, Zhu H, Ma Z, Tang Z, Feng W, Zhang Y, Russell TP, Liu F. Single-layered organic photovoltaics with double cascading charge transport pathways: 18% efficiencies. Nat Commun 2021; 12:309. [PMID: 33436638 PMCID: PMC7803987 DOI: 10.1038/s41467-020-20580-8] [Citation(s) in RCA: 188] [Impact Index Per Article: 62.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Accepted: 12/02/2020] [Indexed: 11/27/2022] Open
Abstract
The chemical structure of donors and acceptors limit the power conversion efficiencies achievable with active layers of binary donor-acceptor mixtures. Here, using quaternary blends, double cascading energy level alignment in bulk heterojunction organic photovoltaic active layers are realized, enabling efficient carrier splitting and transport. Numerous avenues to optimize light absorption, carrier transport, and charge-transfer state energy levels are opened by the chemical constitution of the components. Record-breaking PCEs of 18.07% are achieved where, by electronic structure and morphology optimization, simultaneous improvements of the open-circuit voltage, short-circuit current and fill factor occur. The donor and acceptor chemical structures afford control over electronic structure and charge-transfer state energy levels, enabling manipulation of hole-transfer rates, carrier transport, and non-radiative recombination losses.
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Affiliation(s)
- Ming Zhang
- Frontiers Science Center for Transformative Molecules, In-situ Center for Physical Science, and Center of Hydrogen Science, School of Chemistry and Chemical Engineering, Shanghai Jiao Tong University, Shanghai, 200240, People's Republic of China
| | - Lei Zhu
- Frontiers Science Center for Transformative Molecules, In-situ Center for Physical Science, and Center of Hydrogen Science, School of Chemistry and Chemical Engineering, Shanghai Jiao Tong University, Shanghai, 200240, People's Republic of China
| | - Guanqing Zhou
- Frontiers Science Center for Transformative Molecules, In-situ Center for Physical Science, and Center of Hydrogen Science, School of Chemistry and Chemical Engineering, Shanghai Jiao Tong University, Shanghai, 200240, People's Republic of China
| | - Tianyu Hao
- Frontiers Science Center for Transformative Molecules, In-situ Center for Physical Science, and Center of Hydrogen Science, School of Chemistry and Chemical Engineering, Shanghai Jiao Tong University, Shanghai, 200240, People's Republic of China
| | - Chaoqun Qiu
- Frontiers Science Center for Transformative Molecules, In-situ Center for Physical Science, and Center of Hydrogen Science, School of Chemistry and Chemical Engineering, Shanghai Jiao Tong University, Shanghai, 200240, People's Republic of China
| | - Zhe Zhao
- Frontiers Science Center for Transformative Molecules, In-situ Center for Physical Science, and Center of Hydrogen Science, School of Chemistry and Chemical Engineering, Shanghai Jiao Tong University, Shanghai, 200240, People's Republic of China
| | - Qin Hu
- Department of Polymer Science and Engineering, University of Massachusetts, Amherst, MA, 01003, USA
| | - Bryon W Larson
- Chemistry & Nanoscience Department, National Renewable Energy Laboratory, Golden, Colorado, 80401, USA
| | - Haiming Zhu
- Department of Chemistry, Zhejiang University, Hangzhou, 310027, People's Republic of China
| | - Zaifei Ma
- Center for Advanced Low-dimension Materials, State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Materials Science and Engineering, Donghua University, Shanghai, 201620, People's Republic of China
| | - Zheng Tang
- Center for Advanced Low-dimension Materials, State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Materials Science and Engineering, Donghua University, Shanghai, 201620, People's Republic of China
| | - Wei Feng
- State Key Laboratory of Fluorinated Functional Membrane Materials and Dongyue Future Hydrogen Energy Materials Company, Zibo City, 256401, Shandong Province, People's Republic of China
| | - Yongming Zhang
- Frontiers Science Center for Transformative Molecules, In-situ Center for Physical Science, and Center of Hydrogen Science, School of Chemistry and Chemical Engineering, Shanghai Jiao Tong University, Shanghai, 200240, People's Republic of China
- State Key Laboratory of Fluorinated Functional Membrane Materials and Dongyue Future Hydrogen Energy Materials Company, Zibo City, 256401, Shandong Province, People's Republic of China
| | - Thomas P Russell
- Department of Polymer Science and Engineering, University of Massachusetts, Amherst, MA, 01003, USA
| | - Feng Liu
- Frontiers Science Center for Transformative Molecules, In-situ Center for Physical Science, and Center of Hydrogen Science, School of Chemistry and Chemical Engineering, Shanghai Jiao Tong University, Shanghai, 200240, People's Republic of China.
- State Key Laboratory of Fluorinated Functional Membrane Materials and Dongyue Future Hydrogen Energy Materials Company, Zibo City, 256401, Shandong Province, People's Republic of China.
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15
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Yang JJ, Li ZW, Liu XY, Fang WH, Cui G. Photoinduced electron transfer from carbon nanotubes to fullerenes: C 60versus C 70. Phys Chem Chem Phys 2020; 22:19542-19548. [PMID: 32844829 DOI: 10.1039/d0cp03622f] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Hybrid carbon materials are found to exhibit novel optoelectronic properties at their interfaces, but the related interfacial carrier dynamics is rarely explored theoretically. In this contribution, we have employed density functional theory (DFT) and DFT-based nonadiabatic dynamics methods to explore photoinduced interfacial electron transfer processes at interfaces between a single-walled carbon nanotube with chiral index (6,5) and C60 or C70 (C60@CNT65 and C70@CNT65). We have found that with low E11 excitation, electron transfer takes place from CNT65 to C60 and C70 in both heterojunctions. This process is ultrafast and completed within about 200 fs, which is consistent with recent experiments. Differently, high E22 excitation does not induce electron injection to C60 in C60@CNT65; instead, "hot" electrons produced within CNT65 will be trapped in its higher conduction band for a while because of slow inter-band relaxation. By contrast, in C70@CNT65, high E22 excitation still can lead to ultrafast electron transfer to C70, but only a comparable amount of electrons are transferred (ca. 30%). Interestingly, electrons either remaining on CNT65 or transferred to C70 are trapped in the higher conduction band for a while, similarly, due to slow inter-band relaxation. The present results could be useful to guide the design of excellent interfaces of mixed-dimensional hybrid carbon materials for various optoelectronic applications.
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Affiliation(s)
- Jia-Jia Yang
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing 100875, China.
| | - Zi-Wen Li
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing 100875, China.
| | - Xiang-Yang Liu
- College of Chemistry and Material Science, Sichuan Normal University, Chengdu 610068, China.
| | - Wei-Hai Fang
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing 100875, China.
| | - Ganglong Cui
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing 100875, China.
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16
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Menon A, Slominskii YL, Joseph J, Dimitriev OP, Guldi DM. Reversible Charge Transfer with Single-Walled Carbon Nanotubes Upon Harvesting the Low Energy Part of the Solar Spectrum. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2020; 16:e1906745. [PMID: 32003927 DOI: 10.1002/smll.201906745] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2019] [Revised: 01/15/2020] [Indexed: 06/10/2023]
Abstract
Here, the ability of a novel near-infrared dye to noncovalently self-assemble onto the surface of single-walled carbon nanotubes (SWCNTs) driven by charge-transfer interactions is demonstrated. Steady-state, Raman, and transient absorption spectroscopies corroborate the electron donating character of the near-infrared dye when combined with SWCNTs, in the form of fluorescence quenching of the excited state of the dye, n-doping of SWCNTs, and reversible charge transfer, respectively. Formation of the one-electron oxidized dye as a result of interactions with SWCNTs is supported by spectroelectrochemical measurements. The ultrafast electronic process in the near-infrared dye, once immobilized onto SWCNTs, starts with the formation of excited states, which decay to the ground state via the intermediate population of a fully charge-separated state, with characteristic time constants for the charge separation of 1.5 ps and charge recombination of 25 ps, as derived from the multiwavelength global analysis. Of great relevance is the fact that charge-transfer occurs from the hot excited state of the near-infrared dye to SWCNTs.
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Affiliation(s)
- Arjun Menon
- Department of Chemistry and Pharmacy, Interdisciplinary Center for Molecular Materials, Friedrich-Alexander University of Erlangen-Nürnberg, Egerlandstrasse 3, 91058, Erlangen, Germany
| | - Yuri L Slominskii
- Institute of Organic Chemistry NAS of Ukraine, 5 Murmanska Street, 02660, Kyiv, Ukraine
| | - Jan Joseph
- Department of Chemistry and Pharmacy, Interdisciplinary Center for Molecular Materials, Friedrich-Alexander University of Erlangen-Nürnberg, Egerlandstrasse 3, 91058, Erlangen, Germany
| | - Oleg P Dimitriev
- V. Lashkaryov Institute of Semiconductor Physics, NAS of Ukraine, 41 Nauki Ave, 03028, Kyiv, Ukraine
| | - Dirk M Guldi
- Department of Chemistry and Pharmacy, Interdisciplinary Center for Molecular Materials, Friedrich-Alexander University of Erlangen-Nürnberg, Egerlandstrasse 3, 91058, Erlangen, Germany
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17
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Deng S, Snaider JM, Gao Y, Shi E, Jin L, Schaller RD, Dou L, Huang L. Long-lived charge separation in two-dimensional ligand-perovskite heterostructures. J Chem Phys 2020; 152:044711. [PMID: 32007060 DOI: 10.1063/1.5131801] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Shibin Deng
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, USA
| | - Jordan M. Snaider
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, USA
| | - Yao Gao
- Davidson School of Chemical Engineering, Purdue University, West Lafayette, Indiana 47907, USA
| | - Enzheng Shi
- Davidson School of Chemical Engineering, Purdue University, West Lafayette, Indiana 47907, USA
| | - Linrui Jin
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, USA
| | - Richard D. Schaller
- Center for Nanoscale Materials, Argonne National Laboratory, Argonne, Illinois 60439, USA
- Department of Chemistry, Northwestern University, Evanston, Illinois 60208, USA
| | - Letian Dou
- Davidson School of Chemical Engineering, Purdue University, West Lafayette, Indiana 47907, USA
- Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907, USA
| | - Libai Huang
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, USA
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18
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Li H, Gordeev G, Garrity O, Peyyety NA, Selvasundaram PB, Dehm S, Krupke R, Cambré S, Wenseleers W, Reich S, Zheng M, Fagan JA, Flavel BS. Separation of Specific Single-Enantiomer Single-Wall Carbon Nanotubes in the Large-Diameter Regime. ACS NANO 2020; 14:948-963. [PMID: 31742998 PMCID: PMC6994058 DOI: 10.1021/acsnano.9b08244] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2019] [Accepted: 11/19/2019] [Indexed: 05/06/2023]
Abstract
The enantiomer-level isolation of single-walled carbon nanotubes (SWCNTs) in high concentration and with high purity for nanotubes greater than 1.1 nm in diameter is demonstrated using a two-stage aqueous two-phase extraction (ATPE) technique. In total, five different nanotube species of ∼1.41 nm diameter are isolated, including both metallics and semiconductors. We characterize these populations by absorbance spectroscopy, circular dichroism spectroscopy, resonance Raman spectroscopy, and photoluminescence mapping, revealing and substantiating mod-dependent optical dependencies. Using knowledge of the competitive adsorption of surfactants to the SWCNTs that controls partitioning within the ATPE separation, we describe an advanced acid addition methodology that enables the fine control of the separation of these select nanotubes. Furthermore, we show that endohedral filling is a previously unrecognized but important factor to ensure a homogeneous starting material and further enhance the separation yield, with the best results for alkane-filled SWCNTs, followed by empty SWCNTs, with the intrinsic inhomogeneity of water-filled SWCNTs causing them to be worse for separations. Lastly, we demonstrate the potential use of these nanotubes in field-effect transistors.
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Affiliation(s)
- Han Li
- Institute
of Nanotechnology, Karlsruhe Institute of
Technology, Karlsruhe 76021, Germany
| | - Georgy Gordeev
- Department
of Physics, Freie Universität Berlin, Berlin 14195, Germany
| | - Oisin Garrity
- Department
of Physics, Freie Universität Berlin, Berlin 14195, Germany
| | - Naga Anirudh Peyyety
- Institute
of Nanotechnology, Karlsruhe Institute of
Technology, Karlsruhe 76021, Germany
- Institute
of Materials Science, Technische Universität
Darmstadt, Darmstadt 64287, Germany
| | - Pranauv Balaji Selvasundaram
- Institute
of Nanotechnology, Karlsruhe Institute of
Technology, Karlsruhe 76021, Germany
- Institute
of Materials Science, Technische Universität
Darmstadt, Darmstadt 64287, Germany
| | - Simone Dehm
- Institute
of Nanotechnology, Karlsruhe Institute of
Technology, Karlsruhe 76021, Germany
| | - Ralph Krupke
- Institute
of Nanotechnology, Karlsruhe Institute of
Technology, Karlsruhe 76021, Germany
- Institute
of Materials Science, Technische Universität
Darmstadt, Darmstadt 64287, Germany
| | - Sofie Cambré
- Physics
Department, University of Antwerp, Antwerp 2020, Belgium
| | - Wim Wenseleers
- Physics
Department, University of Antwerp, Antwerp 2020, Belgium
| | - Stephanie Reich
- Department
of Physics, Freie Universität Berlin, Berlin 14195, Germany
| | - Ming Zheng
- Materials
Science and Engineering Division, National
Institute of Standards and Technology, Gaithersburg, Maryland 20899, United States
| | - Jeffrey A. Fagan
- Materials
Science and Engineering Division, National
Institute of Standards and Technology, Gaithersburg, Maryland 20899, United States
| | - Benjamin S. Flavel
- Institute
of Nanotechnology, Karlsruhe Institute of
Technology, Karlsruhe 76021, Germany
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19
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Blackburn JL, Zhang H, Myers AR, Dunklin JR, Coffey DC, Hirsch RN, Vigil-Fowler D, Yun SJ, Cho BW, Lee YH, Miller EM, Rumbles G, Reid OG. Measuring Photoexcited Free Charge Carriers in Mono- to Few-Layer Transition-Metal Dichalcogenides with Steady-State Microwave Conductivity. J Phys Chem Lett 2020; 11:99-107. [PMID: 31790587 DOI: 10.1021/acs.jpclett.9b03117] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Photoinduced generation of mobile charge carriers is the fundamental process underlying many applications, such as solar energy harvesting, solar fuel production, and efficient photodetectors. Monolayer transition-metal dichalcogenides (TMDCs) are an attractive model system for studying photoinduced carrier generation mechanisms in low-dimensional materials because they possess strong direct band gap absorption, large exciton binding energies, and are only a few atoms thick. While a number of studies have observed charge generation in neat TMDCs for photoexcitation at, above, or even below the optical band gap, the role of nonlinear processes (resulting from high photon fluences), defect states, excess charges, and layer interactions remains unclear. In this study, we introduce steady-state microwave conductivity (SSMC) spectroscopy for measuring charge generation action spectra in a model WS2 mono- to few-layer TMDC system at fluences that coincide with the terrestrial solar flux. Despite utilizing photon fluences well below those used in previous pump-probe measurements, the SSMC technique is sensitive enough to easily resolve the photoconductivity spectrum arising in mono- to few-layer WS2. By correlating SSMC with other spectroscopy and microscopy experiments, we find that photoconductivity is observed predominantly for excitation wavelengths resonant with the excitonic transition of the multilayer portions of the sample, the density of which can be controlled by the synthesis conditions. These results highlight the potential of layer engineering as a route toward achieving high yields of photoinduced charge carriers in neat TMDCs, with implications for a broad range of optoelectronic applications.
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Affiliation(s)
- Jeffrey L Blackburn
- Chemistry and Nanoscience Center , National Renewable Energy Laboratory , 15013 Denver West Parkway , Golden , Colorado 80401 , United States
| | - Hanyu Zhang
- Chemistry and Nanoscience Center , National Renewable Energy Laboratory , 15013 Denver West Parkway , Golden , Colorado 80401 , United States
| | - Alexis R Myers
- Chemistry and Nanoscience Center , National Renewable Energy Laboratory , 15013 Denver West Parkway , Golden , Colorado 80401 , United States
- Department of Chemistry and Biochemistry , University of Colorado Boulder , Boulder , Colorado 80309 , United States
| | - Jeremy R Dunklin
- Chemistry and Nanoscience Center , National Renewable Energy Laboratory , 15013 Denver West Parkway , Golden , Colorado 80401 , United States
| | - David C Coffey
- Department of Physics , Warren Wilson College , 701 Warren Wilson Road , Swannanoa , North Carolina 28778 , United States
| | - Rebecca N Hirsch
- Department of Chemistry and Biochemistry , University of Colorado Boulder , Boulder , Colorado 80309 , United States
| | - Derek Vigil-Fowler
- Chemistry and Nanoscience Center , National Renewable Energy Laboratory , 15013 Denver West Parkway , Golden , Colorado 80401 , United States
| | - Seok Joon Yun
- Center for Integrated Nanostructure Physics (CINAP) , Institute for Basic Science (IBS) , Suwon 16419 , Republic of Korea
| | - Byeong Wook Cho
- Center for Integrated Nanostructure Physics (CINAP) , Institute for Basic Science (IBS) , Suwon 16419 , Republic of Korea
- Department of Energy Science , Sungkyunkwan University , Suwon 16419 , Republic of Korea
| | - Young Hee Lee
- Center for Integrated Nanostructure Physics (CINAP) , Institute for Basic Science (IBS) , Suwon 16419 , Republic of Korea
- Department of Energy Science , Sungkyunkwan University , Suwon 16419 , Republic of Korea
| | - Elisa M Miller
- Chemistry and Nanoscience Center , National Renewable Energy Laboratory , 15013 Denver West Parkway , Golden , Colorado 80401 , United States
| | - Garry Rumbles
- Chemistry and Nanoscience Center , National Renewable Energy Laboratory , 15013 Denver West Parkway , Golden , Colorado 80401 , United States
- Renewable and Sustainable Energy Institute , University of Colorado Boulder , Boulder , Colorado 80309 , United States
| | - Obadiah G Reid
- Chemistry and Nanoscience Center , National Renewable Energy Laboratory , 15013 Denver West Parkway , Golden , Colorado 80401 , United States
- Renewable and Sustainable Energy Institute , University of Colorado Boulder , Boulder , Colorado 80309 , United States
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20
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Arias DH, Sulas-Kern DB, Hart SM, Kang HS, Hao J, Ihly R, Johnson JC, Blackburn JL, Ferguson AJ. Effect of nanotube coupling on exciton transport in polymer-free monochiral semiconducting carbon nanotube networks. NANOSCALE 2019; 11:21196-21206. [PMID: 31663591 DOI: 10.1039/c9nr07821e] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Semiconducting single-walled carbon nanotubes (s-SWCNTs) are attractive light-harvesting components for solar photoconversion schemes and architectures, and selective polymer extraction has emerged as a powerful route to obtain highly pure s-SWCNT samples for electronic applications. Here we demonstrate a novel method for producing electronically coupled thin films of near-monochiral s-SWCNTs without wrapping polymer. Detailed steady-state and transient optical studies on such samples provide new insights into the role of the wrapping polymer on controlling intra-bundle nanotube-nanotube interactions and exciton energy transfer within and between bundles. Complete removal of polymer from the networks results in rapid exciton trapping within nanotube bundles, limiting long-range exciton transport. The results suggest that intertube electronic coupling and associated exciton delocalization across multiple tubes can limit diffusive exciton transport. The complex relationship observed here between exciton delocalization, trapping, and long-range transport, helps to inform the design, preparation, and implementation of carbon nanotube networks as active elements for optical and electronic applications.
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Affiliation(s)
- Dylan H Arias
- Chemistry & Nanoscience Center, National Renewable Energy Laboratory, Golden, Colorado 80401, USA.
| | - Dana B Sulas-Kern
- Materials Science Center, National Renewable Energy Laboratory, Golden, Colorado 80401, USA
| | - Stephanie M Hart
- Chemistry & Nanoscience Center, National Renewable Energy Laboratory, Golden, Colorado 80401, USA.
| | - Hyun Suk Kang
- Chemistry & Nanoscience Center, National Renewable Energy Laboratory, Golden, Colorado 80401, USA.
| | - Ji Hao
- Chemistry & Nanoscience Center, National Renewable Energy Laboratory, Golden, Colorado 80401, USA.
| | - Rachelle Ihly
- Chemistry & Nanoscience Center, National Renewable Energy Laboratory, Golden, Colorado 80401, USA.
| | - Justin C Johnson
- Chemistry & Nanoscience Center, National Renewable Energy Laboratory, Golden, Colorado 80401, USA.
| | - Jeffrey L Blackburn
- Materials Science Center, National Renewable Energy Laboratory, Golden, Colorado 80401, USA
| | - Andrew J Ferguson
- Chemistry & Nanoscience Center, National Renewable Energy Laboratory, Golden, Colorado 80401, USA.
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21
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Slow charge transfer from pentacene triplet states at the Marcus optimum. Nat Chem 2019; 12:63-70. [PMID: 31767991 DOI: 10.1038/s41557-019-0367-x] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2018] [Accepted: 10/04/2019] [Indexed: 11/08/2022]
Abstract
Singlet fission promises to surpass the Shockley-Queisser limit for single-junction solar cell efficiency through the production of two electron-hole pairs per incident photon. However, this promise has not been fulfilled because singlet fission produces two low-energy triplet excitons that have been unexpectedly difficult to dissociate into free charges. To understand this phenomenon, we study charge separation from triplet excitons in polycrystalline pentacene using an electrochemical series of 12 different guest electron-acceptor molecules with varied reduction potentials. We observe separate optima in the charge yield as a function of driving force for singlet and triplet excitons, including inverted regimes for the dissociation of both states. Molecular acceptors can thus provide a strategic advantage to singlet fission solar cells by suppressing singlet dissociation at optimal driving forces for triplet dissociation. However, even at the optimal driving force, the rate constant for charge transfer from the triplet state is surprisingly small, ~107 s-1, presenting a previously unidentified obstacle to the design of efficient singlet fission solar cells.
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22
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Watkins KJ, Parkinson BA. Spectral Sensitization of n- and p-Type Gallium Phosphide Single Crystals with Single-Walled Semiconducting Carbon Nanotubes. J Phys Chem Lett 2019; 10:3604-3609. [PMID: 31188608 DOI: 10.1021/acs.jpclett.9b00694] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
The spectral sensitization of single-crystal p-GaP by semiconducting single-walled carbon nanotubes (s-SWCNT) via hole injection into the p-GaP valence band is reported. The results are compared to SWNCT sensitized n-type single-crystal substrates: TiO2, SnO2, and n-GaP. It was found that the sensitized photocurrents from CoMoCAT and HiPco s-SWCNTs were from a hole injection mechanism on all substrates, even when electron injection into the conduction band should be energetically favored. The results suggest an intrinsic p-type character of the s-SWCNTs surface films investigated in this work.
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Affiliation(s)
- Kevin J Watkins
- Department of Chemistry and School of Energy Resources , University of Wyoming , Laramie , Wyoming 82071 , United States
| | - Bruce A Parkinson
- Department of Chemistry and School of Energy Resources , University of Wyoming , Laramie , Wyoming 82071 , United States
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23
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Kubie L, Parkinson BA. Photosensitization of Single-Crystal Oxide Substrates with Quantum Confined Semiconductors. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2019; 35:5997-6004. [PMID: 30145898 DOI: 10.1021/acs.langmuir.8b00720] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Dye-sensitized solar cells have been studied for many years as a potential inexpensive and scalable alternative to silicon solar cells. They have recently expanded their list of photosensitizers to include quantum dots. In recent years, there has been substantial progress in the field of quantum dot solar cells, with certified efficiencies now reaching 13.4%. Fundamental studies on nanomaterial/semiconductor electrode coupling have led to a deeper understanding of photoinduced electron-transfer processes that are important for both of these devices. This Feature Article will highlight the use of a model system, nanomaterials sensitizing single-crystal oxide substrates, that is useful for investigating how changes in nanomaterial shape, dimensionality, size, and local environment affect the photoinduced charge separation efficiency.
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Affiliation(s)
- Lenore Kubie
- Department of Chemistry and School of Energy Resources , University of Wyoming , Laramie , Wyoming 82071 , United States
| | - Bruce A Parkinson
- Department of Chemistry and School of Energy Resources , University of Wyoming , Laramie , Wyoming 82071 , United States
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24
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Takaguchi Y, Miyake H, Izawa T, Miyamoto D, Sagawa R, Tajima T. Molecular design of benzothiadiazole-based dyes for working with carbon nanotube photocatalysts. PHOSPHORUS SULFUR 2019. [DOI: 10.1080/10426507.2019.1603716] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Affiliation(s)
- Yutaka Takaguchi
- Graduate School of Environmental Science & Technology, Okayama University, Okayama, Japan
| | - Hideaki Miyake
- Graduate School of Sciences & Technology for Innovation, Yamaguchi University, Ube, Japan
| | - Takumi Izawa
- Graduate School of Environmental Science & Technology, Okayama University, Okayama, Japan
| | - Daiki Miyamoto
- Graduate School of Environmental Science & Technology, Okayama University, Okayama, Japan
| | - Ryohei Sagawa
- Graduate School of Environmental Science & Technology, Okayama University, Okayama, Japan
| | - Tomoyuki Tajima
- Graduate School of Environmental Science & Technology, Okayama University, Okayama, Japan
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25
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Ferguson AJ, Reid OG, Nanayakkara SU, Ihly R, Blackburn JL. Efficiency of Charge-Transfer Doping in Organic Semiconductors Probed with Quantitative Microwave and Direct-Current Conductance. J Phys Chem Lett 2018; 9:6864-6870. [PMID: 30457866 DOI: 10.1021/acs.jpclett.8b03074] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Although molecular charge-transfer doping is widely used to manipulate carrier density in organic semiconductors, only a small fraction of charge carriers typically escape the Coulomb potential of dopant counterions to contribute to electrical conductivity. Here, we utilize microwave and direct-current (DC) measurements of electrical conductivity to demonstrate that a high percentage of charge carriers in redox-doped semiconducting single-walled carbon nanotube (s-SWCNT) networks is delocalized as a free carrier density in the π-electron system (estimated as >46% at high doping densities). The microwave and four-point probe conductivities of hole-doped s-SWCNT films quantitatively match over almost 4 orders of magnitude in conductance, indicating that both measurements are dominated by the same population of delocalized carriers. We address the relevance of this surprising one-to-one correspondence by discussing the degree to which local environmental parameters (e.g., tube-tube junctions, Coulombic stabilization, and local bonding environment) may impact the relative magnitudes of each transport measurement.
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Affiliation(s)
- Andrew J Ferguson
- National Renewable Energy Laboratory , Golden , Colorado 80401 , United States
| | - Obadiah G Reid
- National Renewable Energy Laboratory , Golden , Colorado 80401 , United States
- Renewable and Sustainable Energy Institute , University of Colorado Boulder , Boulder , Colorado 80303 , United States
| | | | - Rachelle Ihly
- National Renewable Energy Laboratory , Golden , Colorado 80401 , United States
| | - Jeffrey L Blackburn
- National Renewable Energy Laboratory , Golden , Colorado 80401 , United States
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26
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Kubie L, Watkins KJ, Ihly R, Wladkowski HV, Blackburn JL, Rice WD, Parkinson BA. Optically Generated Free-Carrier Collection from an All Single-Walled Carbon Nanotube Active Layer. J Phys Chem Lett 2018; 9:4841-4847. [PMID: 30085684 DOI: 10.1021/acs.jpclett.8b01850] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Semiconducting single-walled carbon nanotubes' (SWCNTs) broad absorption range and all-carbon composition make them attractive materials for light harvesting. We report photoinduced charge transfer from both multichiral and single-chirality SWCNT films into atomically flat SnO2 and TiO2 crystals. Higher-energy second excitonic SWCNT transitions produce more photocurrent, demonstrating carrier injection rates are competitive with fast hot-exciton relaxation processes. A logarithmic relationship exists between photoinduced electron-transfer driving force and photocarrier collection efficiency, becoming more efficient with smaller diameter SWCNTs. Photocurrents are generated from both conventional sensitization and in the opposite direction with the semiconductor under accumulation and acting as an ohmic contact with only the p-type nanotubes. Finally, we demonstrate that SWCNT surfactant choice and concentration play a large role in photon conversion efficiency and present methods of maximizing photocurrent yields.
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Affiliation(s)
- Lenore Kubie
- Department of Chemistry , University of Wyoming , Laramie , Wyoming 82071 , United States
- Energy Sciences Division , National Renewable Energy Laboratory , Golden , Colorado 80401 , United States
| | - Kevin J Watkins
- Department of Chemistry , University of Wyoming , Laramie , Wyoming 82071 , United States
| | - Rachelle Ihly
- Energy Sciences Division , National Renewable Energy Laboratory , Golden , Colorado 80401 , United States
| | - Henry V Wladkowski
- Department of Physics and Astronomy , University of Wyoming , Laramie , Wyoming 82071 , United States
| | - Jeffrey L Blackburn
- Energy Sciences Division , National Renewable Energy Laboratory , Golden , Colorado 80401 , United States
| | - William D Rice
- Department of Physics and Astronomy , University of Wyoming , Laramie , Wyoming 82071 , United States
| | - Bruce A Parkinson
- Department of Chemistry , University of Wyoming , Laramie , Wyoming 82071 , United States
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27
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Zang X, Singh N, Schwingenschlögl U. Topological characterization of carbon nanotubes. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2018; 30:335301. [PMID: 30033939 DOI: 10.1088/1361-648x/aad21f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
We show that the tight-binding Hamiltonian of any carbon nanotube with C N symmetry can be represented by N decoupled tight-binding Hamiltonians of molecular chains, for which a general pseudospin formulation, characterized by specific paths in a two-dimensional auxiliary space, is developed. The quantum phases therefore are given by a set of N winding numbers of the paths. The paths degenerate to lines and circles for armchair and zigzag carbon nanotubes, respectively. They rotate in the auxiliary space when a magnetic field of varying strength is applied along the carbon nanotube, which gives rise to quantum phase transitions.
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Affiliation(s)
- Xiaoning Zang
- Physical Sciences and Engineering Division (PSE), King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia
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28
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Mentel KK, Serra A, Abreu PE, Arnaut LG. Higher activation barriers can lift exothermic rate restrictions in electron transfer and enable faster reactions. Nat Commun 2018; 9:2903. [PMID: 30046094 PMCID: PMC6060101 DOI: 10.1038/s41467-018-05267-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Accepted: 06/25/2018] [Indexed: 01/08/2023] Open
Abstract
Electron transfer reactions are arguably the simplest chemical reactions but they have not yet ceased to intrigue chemists. Charge-separation and charge-recombination reactions are at the core of life-sustaining processes, molecular electronics and solar cells. Intramolecular electron donor-acceptor systems capture the essential features of these reactions and enable their fundamental understanding. Here, we report intramolecular electron transfers covering a range of 100 kcal mol-1 in exothermicities that show an increase, then a decrease, and finally an increase in rates with the driving force of the reactions. Concomitantly, apparent activation energies change from positive, to negative and finally to positive. Reactions with positive activation energies are found to be faster than analogous reactions with negative effective activation energies. The increase of the reorganization energy with the driving force of the reactions can explain the peculiar free-energy relationship observed in this work.
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Affiliation(s)
- Kamila K Mentel
- Chemistry Department, University of Coimbra, Coimbra, 3004-535, Portugal
| | - Arménio Serra
- Chemical Engineering Department, University of Coimbra, Coimbra, 3030-790, Portugal
| | - Paulo E Abreu
- Chemistry Department, University of Coimbra, Coimbra, 3004-535, Portugal
| | - Luis G Arnaut
- Chemistry Department, University of Coimbra, Coimbra, 3004-535, Portugal.
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29
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van Bezouw S, Arias DH, Ihly R, Cambré S, Ferguson AJ, Campo J, Johnson JC, Defillet J, Wenseleers W, Blackburn JL. Diameter-Dependent Optical Absorption and Excitation Energy Transfer from Encapsulated Dye Molecules toward Single-Walled Carbon Nanotubes. ACS NANO 2018; 12:6881-6894. [PMID: 29965726 PMCID: PMC6083417 DOI: 10.1021/acsnano.8b02213] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2018] [Accepted: 06/20/2018] [Indexed: 05/12/2023]
Abstract
The hollow cores and well-defined diameters of single-walled carbon nanotubes (SWCNTs) allow for creation of one-dimensional hybrid structures by encapsulation of various molecules. Absorption and near-infrared photoluminescence-excitation (PLE) spectroscopy reveal that the absorption spectrum of encapsulated 1,3-bis[4-(dimethylamino)phenyl]-squaraine dye molecules inside SWCNTs is modulated by the SWCNT diameter, as observed through excitation energy transfer (EET) from the encapsulated molecules to the SWCNTs, implying a strongly diameter-dependent stacking of the molecules inside the SWCNTs. Transient absorption spectroscopy, simultaneously probing the encapsulated dyes and the host SWCNTs, demonstrates this EET, which can be used as a route to diameter-dependent photosensitization, to be fast (sub-picosecond). A wide series of SWCNT samples is systematically characterized by absorption, PLE, and resonant Raman scattering (RRS), also identifying the critical diameter for squaraine filling. In addition, we find that SWCNT filling does not limit the selectivity of subsequent separation protocols (including polyfluorene polymers for isolating only semiconducting SWCNTs and aqueous two-phase separation for enrichment of specific SWCNT chiralities). The design of these functional hybrid systems, with tunable dye absorption, fast and efficient EET, and the ability to remove all metallic SWCNTs by subsequent separation, demonstrates potential for implementation in photoconversion devices.
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Affiliation(s)
- Stein van Bezouw
- Physics
Department, University of Antwerp, Universiteitsplein 1, B-2610 Antwerp, Belgium
| | - Dylan H. Arias
- Chemistry
& Nanoscience Center, National Renewable
Energy Laboratory, Golden, Colorado 80401, United States
| | - Rachelle Ihly
- Chemistry
& Nanoscience Center, National Renewable
Energy Laboratory, Golden, Colorado 80401, United States
| | - Sofie Cambré
- Physics
Department, University of Antwerp, Universiteitsplein 1, B-2610 Antwerp, Belgium
| | - Andrew J. Ferguson
- Chemistry
& Nanoscience Center, National Renewable
Energy Laboratory, Golden, Colorado 80401, United States
| | - Jochen Campo
- Physics
Department, University of Antwerp, Universiteitsplein 1, B-2610 Antwerp, Belgium
| | - Justin C. Johnson
- Chemistry
& Nanoscience Center, National Renewable
Energy Laboratory, Golden, Colorado 80401, United States
| | - Joeri Defillet
- Physics
Department, University of Antwerp, Universiteitsplein 1, B-2610 Antwerp, Belgium
| | - Wim Wenseleers
- Physics
Department, University of Antwerp, Universiteitsplein 1, B-2610 Antwerp, Belgium
| | - Jeffrey L. Blackburn
- Chemistry
& Nanoscience Center, National Renewable
Energy Laboratory, Golden, Colorado 80401, United States
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30
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Shayan K, He X, Luo Y, Rabut C, Li X, Hartmann NF, Blackburn JL, Doorn SK, Htoon H, Strauf S. Suppression of exciton dephasing in sidewall-functionalized carbon nanotubes embedded into metallo-dielectric antennas. NANOSCALE 2018; 10:12631-12638. [PMID: 29943788 DOI: 10.1039/c8nr03542c] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Covalent functionalization of single-walled carbon nanotubes (SWCNTs) is a promising route to enhance the quantum yield of exciton emission and can lead to single-photon emission at room temperature. However, the spectral linewidth of the defect-related E11* emission remains rather broad. Here, we systematically investigate the low-temperature exciton emission of individual SWCNTs that have been dispersed with sodium-deoxycholate (DOC) and polyfluorene (PFO-BPy), are grown by laser vaporization (LV) or by CoMoCat techniques and are functionalized with oxygen as well as 3,5-dichlorobenzene groups. The E11 excitons in oxygen-functionalized SWCNTs remain rather broad with up to 10 meV linewidth while exciton emission from 3,5-dichlorobenzene functionalized SWCNTs is found to be about one order of magnitude narrower. In all cases, wrapping with PFO-BPy provides significantly better protection against pump induced dephasing compared to DOC. To further study the influence of exciton localization on pump-induced dephasing, we have embedded the functionalized SWCNTs into metallo-dielectric antenna cavities to maximize light collection. We show that 0D excitons attributed to the E11* emission of 3,5-dichlorobenzene quantum defects of LV-grown SWCNTs can display near resolution-limited linewidths down to 35 μeV. Interestingly, these 0D excitons give rise to a 3-fold suppressed pump-induced exciton dephasing compared to the E11 excitons in the same SWCNT. These findings provide a foundation to build a unified description of the emergence of novel optical behavior from the interplay of covalently introduced defects, dispersants, and exciton confinement in SWCNTs and might further lead to the realization of indistinguishable photons from carbon nanotubes.
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Affiliation(s)
- Kamran Shayan
- Department of Physics, Stevens Institute of Technology, Hoboken, NJ 07030, USA.
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31
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Matsuda W, Sakurai T, Ghosh G, Ghosh S, Seki S. Transient Optical-Microwave Spectroscopy for Electron Mobility Assessment in Solids and Gels: A Comprehensive Approach. J PHOTOPOLYM SCI TEC 2018. [DOI: 10.2494/photopolymer.31.91] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Wakana Matsuda
- Department of Molecular Engineering, Graduate School of Engineering, Kyoto University
| | - Tsuneaki Sakurai
- Department of Molecular Engineering, Graduate School of Engineering, Kyoto University
| | - Goutam Ghosh
- Polymer Science Unit, Indian Association for the Cultivation of Science
| | - Suhrit Ghosh
- Polymer Science Unit, Indian Association for the Cultivation of Science
| | - Shu Seki
- Department of Molecular Engineering, Graduate School of Engineering, Kyoto University
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32
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Murakami N, Miyake H, Tajima T, Nishikawa K, Hirayama R, Takaguchi Y. Enhanced Photosensitized Hydrogen Production by Encapsulation of Ferrocenyl Dyes into Single-Walled Carbon Nanotubes. J Am Chem Soc 2018; 140:3821-3824. [DOI: 10.1021/jacs.7b12845] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Noritake Murakami
- Graduate School of Environmental and Life Science, Okayama University, 3-1-1 Tsushima-naka, Kita-ku, Okayama 700-8530, Japan
| | - Hideaki Miyake
- Graduate School of Sciences and Technology for Innovation, Yamaguchi University, 2-16-1 Tokiwadai, Ube, Yamaguchi 755-8611, Japan
| | - Tomoyuki Tajima
- Graduate School of Environmental and Life Science, Okayama University, 3-1-1 Tsushima-naka, Kita-ku, Okayama 700-8530, Japan
| | - Kakeru Nishikawa
- Graduate School of Environmental and Life Science, Okayama University, 3-1-1 Tsushima-naka, Kita-ku, Okayama 700-8530, Japan
| | - Ryutaro Hirayama
- Graduate School of Environmental and Life Science, Okayama University, 3-1-1 Tsushima-naka, Kita-ku, Okayama 700-8530, Japan
| | - Yutaka Takaguchi
- Graduate School of Environmental and Life Science, Okayama University, 3-1-1 Tsushima-naka, Kita-ku, Okayama 700-8530, Japan
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33
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Ishimoto K, Tajima T, Miyake H, Yamagami M, Kurashige W, Negishi Y, Takaguchi Y. Photo-induced H 2 evolution from water via the dissociation of excitons in water-dispersible single-walled carbon nanotube sensitizers. Chem Commun (Camb) 2018; 54:393-396. [PMID: 29250643 DOI: 10.1039/c7cc07194a] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
To observe a clear-cut example of the formation of mobile carriers from excitons on semiconducting single-walled carbon nanotubes (s-SWCNTs) surrounded by a medium with a high dielectric constant, water-dispersible s-SWCNT nanocomposites were fabricated by physical modifications using poly(amidoamine) dendrimers that contain an aliphatic core. The evolution of H2 from water using these s-SWCNT/dendrimer nanocomposites as photosensitizers under irradiation with visible light demonstrated a photo-induced electron transfer from the s-SWCNTs to the co-catalysts.
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Affiliation(s)
- Kango Ishimoto
- Graduate School of Environmental and Life Science, Okayama University, 3-1-1 Tsushima-Naka, Kita-ku, Okayama 700-8530, Japan.
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34
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Sosorev AY, Godovsky DY, Paraschuk DY. Hot kinetic model as a guide to improve organic photovoltaic materials. Phys Chem Chem Phys 2018; 20:3658-3671. [DOI: 10.1039/c7cp06158g] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The model yields that the most promising ways to increase the OSC performance are decreasing the reorganization energy, increasing the dielectric permittivity and enhancing the charge delocalization.
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Affiliation(s)
- Andrey Yu. Sosorev
- Faculty of Physics and International Laser Center
- M.V. Lomonosov Moscow State University
- Moscow 119991
- Russia
| | - Dmitry Yu. Godovsky
- Institute of Elementoorganic Compounds
- Russian Academy of Science
- Moscow
- Russia
| | - Dmitry Yu. Paraschuk
- Faculty of Physics and International Laser Center
- M.V. Lomonosov Moscow State University
- Moscow 119991
- Russia
- Enikolopov Institute of Synthetic Polymeric Materials
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35
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Luo Y, Ahmadi ED, Shayan K, Ma Y, Mistry KS, Zhang C, Hone J, Blackburn JL, Strauf S. Purcell-enhanced quantum yield from carbon nanotube excitons coupled to plasmonic nanocavities. Nat Commun 2017; 8:1413. [PMID: 29123125 PMCID: PMC5680202 DOI: 10.1038/s41467-017-01777-w] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2017] [Accepted: 10/14/2017] [Indexed: 11/09/2022] Open
Abstract
Single-walled carbon nanotubes (SWCNTs) are promising absorbers and emitters to enable novel photonic applications and devices but are also known to suffer from low optical quantum yields. Here we demonstrate SWCNT excitons coupled to plasmonic nanocavity arrays reaching deeply into the Purcell regime with Purcell factors (FP) up to FP = 180 (average FP = 57), Purcell-enhanced quantum yields of 62% (average 42%), and a photon emission rate of 15 MHz into the first lens. The cavity coupling is quasi-deterministic since the photophysical properties of every SWCNT are enhanced by at least one order of magnitude. Furthermore, the measured ultra-narrow exciton linewidth (18 μeV) reaches the radiative lifetime limit, which is promising towards generation of transform-limited single photons. To demonstrate utility beyond quantum light sources we show that nanocavity-coupled SWCNTs perform as single-molecule thermometers detecting plasmonically induced heat at cryogenic temperatures in a unique interplay of excitons, phonons, and plasmons at the nanoscale. Single-walled carbon nanotubes offer exciting optoelectronic applications but generally suffer from low quantum yields. Here, Luo et al. demonstrate that coupling nanotubes to plasmonic antennas can lead to large Purcell enhancement and corresponding increase in quantum yield as well as plasmonic thermometry at the single molecule level.
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Affiliation(s)
- Yue Luo
- Department of Physics, Stevens Institute of Technology, Hoboken, NJ, 07030, USA.,Center for Quantum Science and Engineering, Stevens Institute of Technology, Hoboken, NJ, 07030, USA
| | - Ehsaneh D Ahmadi
- Department of Physics, Stevens Institute of Technology, Hoboken, NJ, 07030, USA
| | - Kamran Shayan
- Department of Physics, Stevens Institute of Technology, Hoboken, NJ, 07030, USA.,Center for Quantum Science and Engineering, Stevens Institute of Technology, Hoboken, NJ, 07030, USA
| | - Yichen Ma
- Department of Physics, Stevens Institute of Technology, Hoboken, NJ, 07030, USA.,Center for Quantum Science and Engineering, Stevens Institute of Technology, Hoboken, NJ, 07030, USA
| | - Kevin S Mistry
- National Renewable Energy Laboratory, Golden, CO, 80401, USA
| | - Changjian Zhang
- Department of Mechanical Engineering, Columbia University, New York, NY, 10027, USA
| | - James Hone
- Department of Mechanical Engineering, Columbia University, New York, NY, 10027, USA
| | | | - Stefan Strauf
- Department of Physics, Stevens Institute of Technology, Hoboken, NJ, 07030, USA. .,Center for Quantum Science and Engineering, Stevens Institute of Technology, Hoboken, NJ, 07030, USA.
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36
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Kunai Y, Liu AT, Cottrill AL, Koman VB, Liu P, Kozawa D, Gong X, Strano MS. Observation of the Marcus Inverted Region of Electron Transfer from Asymmetric Chemical Doping of Pristine (n,m) Single-Walled Carbon Nanotubes. J Am Chem Soc 2017; 139:15328-15336. [DOI: 10.1021/jacs.7b04314] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Yuichiro Kunai
- Department of Chemical Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Albert Tianxiang Liu
- Department of Chemical Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Anton L. Cottrill
- Department of Chemical Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Volodymyr B. Koman
- Department of Chemical Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Pingwei Liu
- Department of Chemical Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Daichi Kozawa
- Department of Chemical Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Xun Gong
- Department of Chemical Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Michael S. Strano
- Department of Chemical Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
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37
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Eckstein A, Bertašius V, Jašinskas V, Namal I, Hertel T, Gulbinas V. Carrier photogeneration, drift and recombination in a semiconducting carbon nanotube network. NANOSCALE 2017; 9:12441-12448. [PMID: 28809414 DOI: 10.1039/c7nr03813e] [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
Charge carrier photogeneration, drift and recombination in thin film networks of polymer-wrapped (6,5)-single-wall carbon nanotubes (SWNTs) blended with phenyl-C61-butyric acid methyl ester (PCBM) have been investigated by using transient photocurrent and time-delayed collection field (TDCF) techniques. Three distinct transient photocurrent components on the nano- and microsecond timescales have been identified. We attribute the dominant (>50% of total extracted charge) ultrashort photocurrent component with a decay time below our experimental time-resolution of 2 ns to the intratube hole motion. The second component on the few microsecond timescale is attributed to the intertube hole transfer, while the slowest component is assigned to the electron drift within the PCBM phase. The hole drift distance appears to be limited by gaps in the nanotube percolation network rather than by hole trapping or recombination. Photocurrent saturation was observed when excitation densities reached more than one charge pair per nanotube; we attribute this to the local electric field screening.
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Affiliation(s)
- A Eckstein
- Center for Physical Sciences and Technology, Saulėtekio av. 3, LT-10257 Vilnius, Lithuania.
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38
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Murakami N, Tango Y, Miyake H, Tajima T, Nishina Y, Kurashige W, Negishi Y, Takaguchi Y. SWCNT Photocatalyst for Hydrogen Production from Water upon Photoexcitation of (8, 3) SWCNT at 680-nm Light. Sci Rep 2017; 7:43445. [PMID: 28262708 PMCID: PMC5337977 DOI: 10.1038/srep43445] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2016] [Accepted: 01/23/2017] [Indexed: 11/18/2022] Open
Abstract
Single-walled carbon nanotubes (SWCNTs) are potentially strong optical absorbers with tunable absorption bands depending on their chiral indices (n, m). Their application for solar energy conversion is difficult because of the large binding energy (>100 meV) of electron-hole pairs, known as excitons, produced by optical absorption. Recent development of photovoltaic devices based on SWCNTs as light-absorbing components have shown that the creation of heterojunctions by pairing chirality-controlled SWCNTs with C60 is the key for high power conversion efficiency. In contrast to thin film devices, photocatalytic reactions in a dispersion/solution system triggered by the photoexcitation of SWCNTs have never been reported due to the difficulty of the construction of a well-ordered surface on SWCNTs. Here, we show a clear-cut example of a SWCNT photocatalyst producing H2 from water. Self-organization of a fullerodendron on the SWCNT core affords water-dispersible coaxial nanowires possessing SWCNT/C60 heterojunctions, of which a dendron shell can act as support of a co-catalyst for H2 evolution. Because the band offset between the LUMO levels of (8, 3)SWCNT and C60 satisfactorily exceeds the exciton binding energy to allow efficient exciton dissociation, the (8, 3)SWCNT/fullerodendron coaxial photocatalyst shows H2-evolving activity (QY = 0.015) upon 680-nm illumination, which is E22 absorption of (8, 3) SWCNT.
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Affiliation(s)
- Noritake Murakami
- Graduate School of Environmental and Life Science; Okayama University; 3-1-1 Tsushima-Naka, Kita-ku, Okayama 700-8530, Japan
| | - Yuto Tango
- Graduate School of Environmental and Life Science; Okayama University; 3-1-1 Tsushima-Naka, Kita-ku, Okayama 700-8530, Japan
| | - Hideaki Miyake
- Graduate School of Sciences and Technology for Innovation; Yamaguchi University, 2-16-1 Tokiwadai, Ube, Yamaguchi 755-8611, Japan
| | - Tomoyuki Tajima
- Graduate School of Environmental and Life Science; Okayama University; 3-1-1 Tsushima-Naka, Kita-ku, Okayama 700-8530, Japan
| | - Yuta Nishina
- Research Core for Interdisciplinary Sciences; Okayama University, 3-1-1 Tsushima-Naka, Kita-ku, Okayama 700-8530, Japan
| | - Wataru Kurashige
- Department of Applied Chemistry; Faculty of Science Division I; Tokyo University of Science, 1-3 Kagurazaka, Shinjuku-ku, Tokyo 162-8601, Japan
| | - Yuichi Negishi
- Department of Applied Chemistry; Faculty of Science Division I; Tokyo University of Science, 1-3 Kagurazaka, Shinjuku-ku, Tokyo 162-8601, Japan
| | - Yutaka Takaguchi
- Graduate School of Environmental and Life Science; Okayama University; 3-1-1 Tsushima-Naka, Kita-ku, Okayama 700-8530, Japan
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39
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Inoue J, Tsutsui Y, Choi W, Kubota K, Sakurai T, Seki S. Rapid Evaluation of Electron Mobilities at Semiconductor-Insulator Interfaces in an Ambient Atmosphere by a Contactless Microwave-Based Technique. ACS OMEGA 2017; 2:164-170. [PMID: 31457218 PMCID: PMC6640973 DOI: 10.1021/acsomega.6b00428] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2016] [Accepted: 01/05/2017] [Indexed: 05/31/2023]
Abstract
Intrinsic mobility of electrons at the interfaces between crystalline organic semiconductors and insulating dielectric polymer films was rapidly evaluated in an ambient atmosphere by TRMC@Interfaces, a noncontact and nondestructive method based on dielectric loss spectroscopy of microwaves. By just preparing simple metal-insulator-semiconductor devices, local-scale motions of charge carriers injected into the interface by pulses of gate bias voltage were monitored through reflected microwave changes, resulting in the evaluation of local-scale charge carrier mobilities together with the value of trap density at the interface. The evaluated high electron mobilities of 12 cm2 V-1 s-1 for N,N'-bis(cyclohexyl)naphthalene-1,4,5,8-bis(dicarboximide) (DCy-NDI) and 15 cm2 V-1 s-1 for N,N'-dioctylperylene-1,4,5,8-bis(dicarboximide) (DC 8 -PDI) are the benchmarks for organic semiconducting materials that are comparable with the highest ones reported from the field-effect transistor devices. The present TRMC@Interfaces was found to serve as a rapid screening technique to examine the intrinsic performance of organic semiconducting materials as well as a useful tool enabling the precise discussion on the relationship among their local-scale charge carrier mobility, thin-film morphology, and packing structure.
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Affiliation(s)
- Junichi Inoue
- Department
of Molecular Engineering, Graduate School of Engineering, Kyoto University, Nishikyo-ku, Kyoto 615-8510, Japan
| | - Yusuke Tsutsui
- Department
of Molecular Engineering, Graduate School of Engineering, Kyoto University, Nishikyo-ku, Kyoto 615-8510, Japan
| | - Wookjin Choi
- Department
of Molecular Engineering, Graduate School of Engineering, Kyoto University, Nishikyo-ku, Kyoto 615-8510, Japan
| | - Kai Kubota
- Department
of Molecular Engineering, Graduate School of Engineering, Kyoto University, Nishikyo-ku, Kyoto 615-8510, Japan
- Todaiji
High School, 1375 Misasagi-cho, Nara 631-0803, Japan
| | - Tsuneaki Sakurai
- Department
of Molecular Engineering, Graduate School of Engineering, Kyoto University, Nishikyo-ku, Kyoto 615-8510, Japan
| | - Shu Seki
- Department
of Molecular Engineering, Graduate School of Engineering, Kyoto University, Nishikyo-ku, Kyoto 615-8510, Japan
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40
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Barbero DR, Stranks SD. Functional Single-Walled Carbon Nanotubes and Nanoengineered Networks for Organic- and Perovskite-Solar-Cell Applications. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2016; 28:9668-9685. [PMID: 27633954 DOI: 10.1002/adma.201600659] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2016] [Revised: 05/28/2016] [Indexed: 06/06/2023]
Abstract
Carbon nanotubes have a variety of remarkable electronic and mechanical properties that, in principle, lend them to promising optoelectronic applications. However, the field has been plagued by heterogeneity in the distributions of synthesized tubes and uncontrolled bundling, both of which have prevented nanotubes from reaching their full potential. Here, a variety of recently demonstrated solution-processing avenues is presented, which may combat these challenges through manipulation of nanoscale structures. Recent advances in polymer-wrapping of single-walled carbon nanotubes (SWNTs) are shown, along with how the resulting nanostructures can selectively disperse tubes while also exploiting the favorable properties of the polymer, such as light-harvesting ability. New methods to controllably form nanoengineered SWNT networks with controlled nanotube placement are discussed. These nanoengineered networks decrease bundling, lower the percolation threshold, and enable a strong enhancement in charge conductivity compared to random networks, making them potentially attractive for optoelectronic applications. Finally, SWNT applications, to date, in organic and perovskite photovoltaics are reviewed, and insights as to how the aforementioned recent advancements can lead to improved device performance provided.
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Affiliation(s)
- David R Barbero
- Nano-Engineered Materials and Organic Electronics Laboratory, Umeå Universitet, Umeå, 90187, Sweden
| | - Samuel D Stranks
- Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
- Cavendish Laboratory, JJ Thomson Avenue, Cambridge, CB3 0HE, UK
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Stolz BW, Tune DD, Flavel BS. The effect of dry shear aligning of nanotube thin films on the photovoltaic performance of carbon nanotube-silicon solar cells. BEILSTEIN JOURNAL OF NANOTECHNOLOGY 2016; 7:1486-1491. [PMID: 27826524 PMCID: PMC5082438 DOI: 10.3762/bjnano.7.141] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/15/2016] [Accepted: 10/07/2016] [Indexed: 06/06/2023]
Abstract
Recent results in the field of carbon nanotube-silicon solar cells have suggested that the best performance is obtained when the nanotube film provides good coverage of the silicon surface and when the nanotubes in the film are aligned parallel to the surface. The recently developed process of dry shear aligning - in which shear force is applied to the surface of carbon nanotube thin films in the dry state, has been shown to yield nanotube films that are very flat and in which the surface nanotubes are very well aligned in the direction of shear. It is thus reasonable to expect that nanotube films subjected to dry shear aligning should outperform otherwise identical films formed by other processes. In this work, the fabrication and characterisation of carbon nanotube-silicon solar cells using such films is reported, and the photovoltaic performance of devices produced with and without dry shear aligning is compared.
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Affiliation(s)
- Benedikt W Stolz
- Institute of Nanotechnology, Karlsruhe Institute of Technology, 76021 Karlsruhe, Germany
- Department of Physics, Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany
| | - Daniel D Tune
- Institute of Nanotechnology, Karlsruhe Institute of Technology, 76021 Karlsruhe, Germany
- Centre for Nanoscale Science and Technology, The Flinders University of South Australia, Adelaide 5042, Australia
| | - Benjamin S Flavel
- Institute of Nanotechnology, Karlsruhe Institute of Technology, 76021 Karlsruhe, Germany
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