1
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Li Q, Wu K, Zhu H, Yang Y, He S, Lian T. Charge Transfer from Quantum-Confined 0D, 1D, and 2D Nanocrystals. Chem Rev 2024; 124:5695-5763. [PMID: 38629390 PMCID: PMC11082908 DOI: 10.1021/acs.chemrev.3c00742] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2023] [Revised: 03/29/2024] [Accepted: 04/02/2024] [Indexed: 05/09/2024]
Abstract
The properties of colloidal quantum-confined semiconductor nanocrystals (NCs), including zero-dimensional (0D) quantum dots, 1D nanorods, 2D nanoplatelets, and their heterostructures, can be tuned through their size, dimensionality, and material composition. In their photovoltaic and photocatalytic applications, a key step is to generate spatially separated and long-lived electrons and holes by interfacial charge transfer. These charge transfer properties have been extensively studied recently, which is the subject of this Review. The Review starts with a summary of the electronic structure and optical properties of 0D-2D nanocrystals, followed by the advances in wave function engineering, a novel way to control the spatial distribution of electrons and holes, through their size, dimension, and composition. It discusses the dependence of NC charge transfer on various parameters and the development of the Auger-assisted charge transfer model. Recent advances in understanding multiple exciton generation, decay, and dissociation are also discussed, with an emphasis on multiple carrier transfer. Finally, the applications of nanocrystal-based systems for photocatalysis are reviewed, focusing on the photodriven charge separation and recombination processes that dictate the function and performance of these materials. The Review ends with a summary and outlook of key remaining challenges and promising future directions in the field.
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Affiliation(s)
- Qiuyang Li
- Department
of Physics, University of Michigan, 450 Church St, Ann Arbor, Michigan 48109, United States
| | - Kaifeng Wu
- State
Key Laboratory of Molecular Reaction Dynamics and Collaborative Innovation
Center of Chemistry for Energy Materials (iChEM), Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning 116023, China
- University
of Chinese Academy of Sciences, Beijing 100049, China
| | - Haiming Zhu
- Department
of Chemistry, Zhejiang University, Hangzhou, Zhejiang 310027, China
| | - Ye Yang
- The
State Key Laboratory of Physical Chemistry of Solid Surfaces, iChEM
(Collaborative Innovation Center of Chemistry for Energy Materials),
College of Chemistry & Chemical Engineering, Xiamen University, Xiamen, Fujian 361005, China
| | - Sheng He
- Department
of Chemistry, Emory University, Atlanta, Georgia 30322, United States
| | - Tianquan Lian
- Department
of Chemistry, Emory University, Atlanta, Georgia 30322, United States
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2
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Li YB, Si R, Wen B, Wei XL, Seriani N, Yin WJ, Gebauer R. The Role of Water Molecules on Polaron Behavior at Rutile (110) Surface: A Constrained Density Functional Theory Study. J Phys Chem Lett 2024; 15:1019-1027. [PMID: 38253014 DOI: 10.1021/acs.jpclett.3c02855] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2024]
Abstract
Understanding the behavior of a polaron in contact with water is of significant importance for many photocatalytic applications. We investigated the influence of water on the localization and transport properties of polarons at the rutile (110) surface by constrained density functional theory. An excess electron at a dry surface favors the formation of a small polaron at the subsurface Ti site, with a preferred transport direction along the [001] axis. As the surface is covered by water, the preferred spatial localization of the polarons is moved from the subsurface to the surface. When the water coverage exceeds half a monolayer, the preferred direction of polaron hopping is changed to the [110] direction toward the surface. This characteristic behavior is related to the Ti3d-orbital occupations and crystal field splitting induced by different distorted structures under water coverage. Our work describes the reduced sites that might eventually play a role in photocatalysis for rutile (110) surfaces in a water environment.
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Affiliation(s)
- Yun-Bo Li
- School of Physics and Electronic Science, Hunan University of Science and Technology, Xiangtan 411201, China
- Key Laboratory of Intelligent Sensors and Advanced Sensing Materials of Hunan Province, Hunan University of Science and Technology, Xiangtan 411201, China
| | - Rutong Si
- The Abdus Salam International Centre for Theoretical Physics (ICTP), Strada Costiera 11, I-34151 Trieste, Italy
| | - Bo Wen
- School of Physics and Electronics, Henan University, Kaifeng 475001, China
| | - Xiao-Lin Wei
- Department of Physics and Laboratory for Quantum Engineering and Micro-Nano Energy Technology, Xiangtan University, Xiangtan 411105, Hunan, China
| | - Nicola Seriani
- The Abdus Salam International Centre for Theoretical Physics (ICTP), Strada Costiera 11, I-34151 Trieste, Italy
| | - Wen-Jin Yin
- School of Physics and Electronic Science, Hunan University of Science and Technology, Xiangtan 411201, China
- The Abdus Salam International Centre for Theoretical Physics (ICTP), Strada Costiera 11, I-34151 Trieste, Italy
- Key Laboratory of Intelligent Sensors and Advanced Sensing Materials of Hunan Province, Hunan University of Science and Technology, Xiangtan 411201, China
| | - Ralph Gebauer
- The Abdus Salam International Centre for Theoretical Physics (ICTP), Strada Costiera 11, I-34151 Trieste, Italy
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3
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Zheng F, Wang LW. Multiple k-Point Nonadiabatic Molecular Dynamics for Ultrafast Excitations in Periodic Systems: The Example of Photoexcited Silicon. PHYSICAL REVIEW LETTERS 2023; 131:156302. [PMID: 37897744 DOI: 10.1103/physrevlett.131.156302] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/21/2022] [Revised: 03/22/2023] [Accepted: 08/18/2023] [Indexed: 10/30/2023]
Abstract
With the rapid development of ultrafast experimental techniques for the research of carrier dynamics in solid-state systems, a microscopic understanding of the related phenomena, particularly a first-principle calculation, is highly desirable. Nonadiabatic molecular dynamics (NAMD) offers a real-time direct simulation of the carrier transfer or carrier thermalization. However, when applied to a periodic supercell, there is no cross-k-point transitions during the NAMD simulation. This often leads to a significant underestimation of the transition rate with the single-k-point band structure in a supercell. In this work, based on the surface hopping scheme used for NAMD, we propose a practical method to enable the cross-k transitions for a periodic system. We demonstrate our formalism by showing that the hot electron thermalization process by the multi-k-point NAMD in a small silicon supercell is equivalent to such simulation in a large supercell with a single Γ point. The simulated hot carrier thermalization process of the bulk silicon is compared with the recent ultrafast experiments, which shows excellent agreements. We have also demonstrated our method for the hot carrier coolings in the amorphous silicons and the GaAlAs_{2} solid solutions with the various cation distributions.
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Affiliation(s)
- Fan Zheng
- School of Physical Science and Technology, ShanghaiTech University, Shanghai 201210, China
| | - Lin-Wang Wang
- State Key Laboratory of Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Science, Beijing 100083, China
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4
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Ab initio Nonadiabatic Dynamics of Semiconductor Nanomaterials via Surface Hopping Method. CHINESE J CHEM PHYS 2022. [DOI: 10.1063/1674-0068/cjcp2111247] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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5
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Wang X, Long R. Photoinduced Anomalous Electron Transfer Dynamics at a Lateral MoS 2-Graphene Covalent Junction. J Phys Chem Lett 2021; 12:7553-7559. [PMID: 34351765 DOI: 10.1021/acs.jpclett.1c02169] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Photoinduced charge separation significantly affects the optoelectronic performance of the lateral MoS2-graphene junctions. Generally, an adiabatic mechanism governs electron transfer (ET) at a chemically binding interface. Counterintuitively, we demonstrate, using nonadiabatic (NA) molecular dynamics, that an NA mechanism dominates the ET from MoS2 to graphene in the lateral MoS2-graphene covalent junction. The anomalous ET mechanism arising from the built-in electric field formed at the interface that decreases the donor-acceptor interaction by driving electrons and holes moving to opposite directions. Driven by both graphene and MoS2 vibrations, the photoexcited electrons on MoS2 rapidly transfer into graphene by the NA mechanism within 200 fs, which is faster than electron-phonon energy relaxation and ensures that "hot" electrons can be successfully extracted before they cool and lose energy to heat. The study establishes a mechanistic understanding of the complex charge-phonon dynamics in the lateral MoS2-graphene junctions that are key to optoelectronic and photovoltaic applications.
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Affiliation(s)
- Xiaoli Wang
- College of Chemistry, Key Laboratory of Theoretical & Computational Photochemistry of Ministry of Education, Beijing Normal University, Beijing, 100875, P. R. China
| | - Run Long
- College of Chemistry, Key Laboratory of Theoretical & Computational Photochemistry of Ministry of Education, Beijing Normal University, Beijing, 100875, P. R. China
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6
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Du N, Cui Y, Zhang L, Yang M. Effect of Mn doping on the electron injection in CdSe/TiO 2 quantum dot sensitized solar cells. Phys Chem Chem Phys 2021; 23:647-656. [PMID: 33332495 DOI: 10.1039/d0cp03866k] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Promotion in power conversion efficiency is an appealing task for quantum dot-sensitized solar cells that have emerged as promising materials for the utilization of clean and sustainable energy. Doping of Mn atoms into quantum dots (QD) has been proven to be one of the effective approaches, although the origin of such a promotion remains controversial. While several procedures are involved in the power conversion process, electron injection from the QD to the semiconductor oxide substrate is focused on in this work using first-principles calculations. Based on the Marcus theory, the electron injection rates are evaluated for the quantum dot-sensitized solar cell models in which the pure and Mn-doped core-shell CdSe clusters are deposited on a semiconductor titanium dioxide substrate. Enhanced rates are obtained for the Mn-doped structure, which is in qualitative agreement with the experiments. A large number of dominant injection channels and strong QD-substrate coupling are responsible for the Mn-induced rate enhancement, which could be achieved by manipulating the band structure mapping between the QD and the semiconductor oxide. By addressing the role of an Mn dopant in the electron injection process, strategies for the promotion of electron injection rates are proposed for the design of quantum dot-sensitized solar cells.
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Affiliation(s)
- Ning Du
- Institute of Atomic and Molecular Physics, Sichuan University, Chengdu 610065, China.
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7
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Mai S, González L. Molecular Photochemistry: Recent Developments in Theory. Angew Chem Int Ed Engl 2020; 59:16832-16846. [PMID: 32052547 PMCID: PMC7540682 DOI: 10.1002/anie.201916381] [Citation(s) in RCA: 77] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Revised: 02/12/2020] [Indexed: 12/16/2022]
Abstract
Photochemistry is a fascinating branch of chemistry that is concerned with molecules and light. However, the importance of simulating light-induced processes is reflected also in fields as diverse as biology, material science, and medicine. This Minireview highlights recent progress achieved in theoretical chemistry to calculate electronically excited states of molecules and simulate their photoinduced dynamics, with the aim of reaching experimental accuracy. We focus on emergent methods and give selected examples that illustrate the progress in recent years towards predicting complex electronic structures with strong correlation, calculations on large molecules, describing multichromophoric systems, and simulating non-adiabatic molecular dynamics over long time scales, for molecules in the gas phase or in complex biological environments.
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Affiliation(s)
- Sebastian Mai
- Photonics InstituteVienna University of TechnologyGusshausstrasse 27–291040ViennaAustria
| | - Leticia González
- Institute of Theoretical ChemistryFaculty of ChemistryUniversity of ViennaWähringer Strasse 171090ViennaAustria
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8
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Mai S, González L. Molekulare Photochemie: Moderne Entwicklungen in der theoretischen Chemie. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.201916381] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Sebastian Mai
- Institut für Photonik Technische Universität Wien Gußhausstraße 27–29 1040 Wien Österreich
| | - Leticia González
- Institut für theoretische Chemie Fakultät für Chemie Universität Wien Währinger Straße 17 1090 Wien Österreich
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9
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Zheng F, Wang LW. Ultrafast Hot Carrier Injection in Au/GaN: The Role of Band Bending and the Interface Band Structure. J Phys Chem Lett 2019; 10:6174-6183. [PMID: 31538792 DOI: 10.1021/acs.jpclett.9b02402] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Plasmon photochemistry can potentially play a significant role in photocatalysis. To realize this potential, it is critical to enhance the plasmon excited hot carrier transfer and collection. However, the lack of atomistic understanding of the carrier transfer across the interface, especially when the carrier is still "hot", makes it challenging to design a more efficient system. In this work, we apply the nonadiabatic molecular dynamics simulation to study hot carrier dynamics in the system of a Au nanocluster on top of a GaN surface. By setting up the initial excited hole in Au, the carrier transfer from Au to GaN is found to be on a subpicosecond time scale. The hot hole first cools to the band edge of Au d-states while it transfers to GaN. After the hole has cooled down to the band edge of GaN, we find that some of the charges can return back to Au. By applying different external potentials to mimic the Schottky barrier band bending, the returning charge can be reduced, demonstrating the importance of the internal electric field. Finally, with the understanding of the carrier transfer's pathway, we suggest that a ZnO layer between GaN and Au can effectively block the "cold" carrier from returning back to Au but still allow the hot carrier to transfer from Au to GaN.
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Affiliation(s)
- Fan Zheng
- Joint Center for Artificial Photosynthesis and Materials Sciences Division , Lawrence Berkeley National Laboratory , Berkeley , California 94720 , United States
| | - Lin-Wang Wang
- Joint Center for Artificial Photosynthesis and Materials Sciences Division , Lawrence Berkeley National Laboratory , Berkeley , California 94720 , United States
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10
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Levine BG, Esch MP, Fales BS, Hardwick DT, Peng WT, Shu Y. Conical Intersections at the Nanoscale: Molecular Ideas for Materials. Annu Rev Phys Chem 2019; 70:21-43. [DOI: 10.1146/annurev-physchem-042018-052425] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The ability to predict and describe nonradiative processes in molecules via the identification and characterization of conical intersections is one of the greatest recent successes of theoretical chemistry. Only recently, however, has this concept been extended to materials science, where nonradiative recombination limits the efficiencies of materials for various optoelectronic applications. In this review, we present recent advances in the theoretical study of conical intersections in semiconductor nanomaterials. After briefly introducing conical intersections, we argue that specific defects in materials can induce conical intersections between the ground and first excited electronic states, thus introducing pathways for nonradiative recombination. We present recent developments in theoretical methods, computational tools, and chemical intuition for the prediction of such defect-induced conical intersections. Through examples in various nanomaterials, we illustrate the significance of conical intersections for nanoscience. We also discuss challenges facing research in this area and opportunities for progress.
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Affiliation(s)
- Benjamin G. Levine
- Department of Chemistry, Michigan State University, East Lansing, Michigan 48824, USA
| | - Michael P. Esch
- Department of Chemistry, Michigan State University, East Lansing, Michigan 48824, USA
| | - B. Scott Fales
- Department of Chemistry and the PULSE Institute, Stanford University, Stanford, California 94305, USA
- SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
| | - Dylan T. Hardwick
- Department of Chemistry, Michigan State University, East Lansing, Michigan 48824, USA
| | - Wei-Tao Peng
- Department of Chemistry, Michigan State University, East Lansing, Michigan 48824, USA
| | - Yinan Shu
- Department of Chemistry, University of Minnesota, Minneapolis, Minnesota 55455, USA
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11
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Nam Y, Li L, Lee JY, Prezhdo OV. Strong Influence of Oxygen Vacancy Location on Charge Carrier Losses in Reduced TiO 2 Nanoparticles. J Phys Chem Lett 2019; 10:2676-2683. [PMID: 31066278 DOI: 10.1021/acs.jpclett.9b00987] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Oxygen vacancies in TiO2 nanoparticles are important for charge carrier dynamics, with recent studies reporting contradictory results on TiO2 nanoparticle photocatalytic activity. We demonstrate that ground state multiplicity, defect levels, and formation energies depend strongly on vacancy location. Quantum dynamics simulations show that charges are trapped within several picoseconds and recombine over a broad range of time scales from tens of picoseconds to nanoseconds. Specifically, nanoparticles with missing partially coordinated surface oxygens showed fast recombination, while nanoparticles with missing highly coordinated subsurface oxygens or singly coordinated oxygens at tips showed slow recombination, even slower than in the pristine system. The results are rationalized by energy gaps and electron-hole localization, the latter determining nonadiabatic coupling and quantum coherence time. The diverse charge recombination scenarios revealed by the nonadiabatic dynamics simulations rationalize the contradictory experimental results for photocatalytic activity and provide guidelines for rational design of nanoscale metal oxides for solar energy harvesting and utilization.
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Affiliation(s)
- Yeonsig Nam
- Department of Chemistry , Sungkyunkwan University , Suwon 16419 , Korea
- Department of Chemistry , University of Southern California , Los Angeles , California 90089 , United States
| | - Linqiu Li
- Department of Chemistry , University of Southern California , Los Angeles , California 90089 , United States
| | - Jin Yong Lee
- Department of Chemistry , Sungkyunkwan University , Suwon 16419 , Korea
| | - Oleg V Prezhdo
- Department of Chemistry , University of Southern California , Los Angeles , California 90089 , United States
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12
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Zhang J, Guan M, Lischner J, Meng S, Prezhdo OV. Coexistence of Different Charge-Transfer Mechanisms in the Hot-Carrier Dynamics of Hybrid Plasmonic Nanomaterials. NANO LETTERS 2019; 19:3187-3193. [PMID: 30995064 DOI: 10.1021/acs.nanolett.9b00647] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
Hot-carrier dynamics at the interfaces of semiconductors and nanoclusters is of significant importance for photovoltaic and photocatalytic applications. Plasmon-driven charge separation processes are considered to be only dependent on the type of donor-acceptor interactions, that is, the conventional hot-electron-transfer mechanism for van der Waals interactions and the plasmon-induced interfacial charge-transfer transition mechanism for chemical bonds. Here, we demonstrate that the two mechanisms can coexist in a nanoparticle-semiconductor hybrid nanomaterial, both leading to faster transfer than carrier relaxation. The origin of the two mechanisms is attributed to the spatial polarization of the excited hot carriers, where the longitudinal state couples to semiconductors more strongly than the transverse state. Our findings provide a new insight into the photoinduced carrier dynamics, which is relevant for many applications in solar energy conversion, including efficient water splitting, photocatalysis, and photovoltaics.
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Affiliation(s)
- Jin Zhang
- Departments of Materials and Physics and the Thomas Young Centre for Theory and Simulation of Materials , Imperial College London , London SW7 2AZ , United Kingdom
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics , Chinese Academy of Sciences , Beijing 100190 , P.R. China
- School of Physical Sciences , University of Chinese Academy of Sciences , Beijing 100049 , P.R. China
| | - Mengxue Guan
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics , Chinese Academy of Sciences , Beijing 100190 , P.R. China
- School of Physical Sciences , University of Chinese Academy of Sciences , Beijing 100049 , P.R. China
| | - Johannes Lischner
- Departments of Materials and Physics and the Thomas Young Centre for Theory and Simulation of Materials , Imperial College London , London SW7 2AZ , United Kingdom
| | - Sheng Meng
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics , Chinese Academy of Sciences , Beijing 100190 , P.R. China
- School of Physical Sciences , University of Chinese Academy of Sciences , Beijing 100049 , P.R. China
| | - Oleg V Prezhdo
- Department of Chemistry , University of Southern California , Los Angeles , California 90089 , United States
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13
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Li Y, Mi L, Wang H, Li Y, Liang J. Design, Electron Transfer Process, and Opto-Electronic Property of Solar Cell Using Triphenylamine-Based D-π-A Architectures. MATERIALS (BASEL, SWITZERLAND) 2019; 12:E193. [PMID: 30626107 PMCID: PMC6337444 DOI: 10.3390/ma12010193] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Revised: 12/23/2018] [Accepted: 12/28/2018] [Indexed: 12/04/2022]
Abstract
A series of D-π-A type dyes were designed based on the experimentally synthesized A1 by introducing different functional groups on the donor and π-spacer, and the optical and electrical properties were calculated by using density functional theory (DFT) and time-dependent DFT (TD-DFT). P1⁻P6 present highest light harvesting efficiency (LHE), driving force of electron injection ( Δ G i n j e c t ), reorganization energy ( Δ G r e g ) and e V O C . These critical parameters have a close relationship with the short-circuit current density ( J S C ) and open-circuit photovoltage ( V O C ), and lead to P1⁻P6 will exhibit higher efficiency. D4 also exhibit superior properties in the driving force of electron injection ( Δ G i n j e c t ), reorganization energy ( Δ G r e g ), which will lead to a higher short-circuit current density ( J S C ). We hope that these results will be helpful for experiments to synthesize new and highly efficient dyes.
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Affiliation(s)
- Yuanchao Li
- College of Science, Northeast Forestry University, Harbin 150040, China.
| | - Lu Mi
- College of Science, Northeast Forestry University, Harbin 150040, China.
| | - Haibin Wang
- College of Science, Northeast Forestry University, Harbin 150040, China.
| | - Yuanzuo Li
- College of Science, Northeast Forestry University, Harbin 150040, China.
| | - Jianping Liang
- Key Lab of Materials Modification, Ministry of Education, Dalian University of Technology, Dalian 116024, China.
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14
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Kaledin AL, Hill CL, Lian T, Musaev DG. A bulk adjusted linear combination of atomic orbitals (BA-LCAO) approach for nanoparticles. J Comput Chem 2018; 40:212-221. [PMID: 30284306 DOI: 10.1002/jcc.25373] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2018] [Revised: 05/15/2018] [Accepted: 05/18/2018] [Indexed: 11/11/2022]
Abstract
We describe a bulk adjusted linear combination of atomic orbitals (BA-LCAO) approach for nanoparticles. In this method, we apply a many-body scaling function (in similar manner as in the environment-modified total energy based tight-binding method) to the DFT-derived diatomic AO interaction potentials (like in the conventional orbital-based density-functional tight binding approach) strictly according to atomic valences acquired naturally in a bulk structure. This modification, (a) facilitates all atom orbital-based electronic structure calculations of charge carrier dynamics in nanoscale structures with a molecular acceptor, and (b) allows to closely match high-level density functional calculation data (previously adjusted to the available experimental findings) for bulk structures. To advance practical application of the BA-LCAO approach we parameterize the Hamiltonian of wurtzite CdSe by fitting its band structure to a high-level DFT reference, corrected for experimentally measured band edges. Here, unlike in conventional DFTB approach, we: (1) use hydrogen-like AOs for the basis as exact atomic eigenfunctions, while orbital energies of which are taken from experimentally measured ionization potentials, and (2) parameterize the many-body scaling functions rather than the atomic wavefunctions. Development of this approach and parameters is guided by our goals to devise a method capable of simultaneously treating the problems of (i) interfacial electron/hole transfer between finite, variable size nanoparticles and electron scavenging molecules, and (ii) high-energy electronic transitions (Auger transitions) that mediate multi-exciton decay in quantum dots. Electronic structure results are described for CdSe quantum dots of various sizes. © 2018 Wiley Periodicals, Inc.
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Affiliation(s)
- Alexey L Kaledin
- Cherry L. Emerson Center for Scientific Computation and Department of Chemistry, Emory University, Atlanta, 30322, Georgia
| | - Craig L Hill
- Cherry L. Emerson Center for Scientific Computation and Department of Chemistry, Emory University, Atlanta, 30322, Georgia
| | - Tianquan Lian
- Cherry L. Emerson Center for Scientific Computation and Department of Chemistry, Emory University, Atlanta, 30322, Georgia
| | - Djamaladdin G Musaev
- Cherry L. Emerson Center for Scientific Computation and Department of Chemistry, Emory University, Atlanta, 30322, Georgia
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15
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Abstract
We show that the importance sampling technique can effectively augment the range of problems where the nuclear ensemble approach can be applied. A sampling probability distribution function initially determines the collection of initial conditions for which calculations are performed, as usual. Then, results for a distinct target distribution are computed by introducing compensating importance sampling weights for each sampled point. This mapping between the two probability distributions can be performed whenever they are both explicitly constructed. Perhaps most notably, this procedure allows for the computation of temperature dependent observables. As a test case, we investigated the UV absorption spectra of phenol, which has been shown to have a marked temperature dependence. Application of the proposed technique to a range that covers 500 K provides results that converge to those obtained with conventional sampling. We further show that an overall improved rate of convergence is obtained when sampling is performed at intermediate temperatures. The comparison between calculated and the available measured cross sections is very satisfactory, as the main features of the spectra are correctly reproduced. As a second test case, one of Tully's classical models was revisited, and we show that the computation of dynamical observables also profits from the importance sampling technique. In summary, the strategy developed here can be employed to assess the role of temperature for any property calculated within the nuclear ensemble method, with the same computational cost as doing so for a single temperature.
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Affiliation(s)
- Fábris Kossoski
- Instituto de Fı́sica "Gleb Wataghin" , Universidade Estadual de Campinas , 13083-859 Campinas , São Paulo , Brazil.,Aix Marseille Univ , CNRS, ICR , Marseille , France
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16
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Zhang Z, Liu L, Fang WH, Long R, Tokina MV, Prezhdo OV. Plasmon-Mediated Electron Injection from Au Nanorods into MoS2: Traditional versus Photoexcitation Mechanism. Chem 2018. [DOI: 10.1016/j.chempr.2018.02.025] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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17
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Zhang Z, Fang WH, Tokina MV, Long R, Prezhdo OV. Rapid Decoherence Suppresses Charge Recombination in Multi-Layer 2D Halide Perovskites: Time-Domain Ab Initio Analysis. NANO LETTERS 2018. [PMID: 29533630 DOI: 10.1021/acs.nanolett.8b00035] [Citation(s) in RCA: 80] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Two-dimensional (2D) Ruddlesden-Popper halide perovskites are appealing candidates for optoelectronics and photovoltaics. Nonradiative electron-hole recombination constitutes a major pathway for charge and energy losses in these materials. Surprisingly, experimental recombination is slower in multilayers than a monolayer, even though multilayer systems have smaller energy gaps and higher frequency phonons that should accelerate the recombination. Focusing on (BA)2(MA) n-1Pb nI3 n+1 with n = 1 and 3, BA = CH3(CH2)3NH3, and MA = CH3NH3, we show that it is the enhancement of elastic electron-phonon scattering that suppresses charge recombination for n = 3, by causing rapid loss of electronic coherence. The scattering is enhanced in the multilayer 2D perovskites because, in contrast to the monolayer, they contain MA cations embedded into the inorganic Pb-I lattice. Although MAs do not contribute directly to electron and hole wave functions, they perturb the Pb-I lattice and create strong electric fields that interact with the charges. The rapid loss of coherence explains long excited state lifetimes that extend into nanoseconds. Both electron-hole recombination and coherence times show excellent agreement with the corresponding lifetime and line width measurements. The simulations rationalize the observed dependence of excited state lifetime in 2D layered halide perovskites on layer thickness and advance our understanding of the atomistic mechanisms underlying charge-phonon dynamics in nanoscale materials.
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Affiliation(s)
- Zhaosheng Zhang
- College of Chemistry, Key Laboratory of Theoretical & Computational Photochemistry of Ministry of Education , Beijing Normal University , Beijing , 100875 , P. R. China
| | - Wei-Hai Fang
- College of Chemistry, Key Laboratory of Theoretical & Computational Photochemistry of Ministry of Education , Beijing Normal University , Beijing , 100875 , P. R. China
| | - Marina V Tokina
- Department of Chemistry , University of Southern California , Los Angeles , California 90089 , United States
| | - Run Long
- College of Chemistry, Key Laboratory of Theoretical & Computational Photochemistry of Ministry of Education , Beijing Normal University , Beijing , 100875 , P. R. China
| | - Oleg V Prezhdo
- Department of Chemistry , University of Southern California , Los Angeles , California 90089 , United States
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18
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Liu L, Fang WH, Long R, Prezhdo OV. Lewis Base Passivation of Hybrid Halide Perovskites Slows Electron-Hole Recombination: Time-Domain Ab Initio Analysis. J Phys Chem Lett 2018; 9:1164-1171. [PMID: 29461842 DOI: 10.1021/acs.jpclett.8b00177] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Nonradiative electron-hole recombination plays a key role in determining photon conversion efficiencies in solar cells. Experiments demonstrate significant reduction in the recombination rate upon passivation of methylammonium lead iodide perovskite with Lewis base molecules. Using nonadiabatic molecular dynamics combined with time-domain density functional theory, we find that the nonradiative charge recombination is decelerated by an order of magnitude upon adsorption of the molecules. Thiophene acts by the traditional passivation mechanism, forcing electron density away from the surface. In contrast, pyridine localizes the electron at the surface while leaving it energetically near the conduction band edge. This is because pyridine creates a stronger coordinative bond with a lead atom of the perovskite and has a lower energy unoccupied orbital compared with thiophene due to the more electronegative nitrogen atom relative to thiophene's sulfur. Both molecules reduce two-fold the nonadiabatic coupling and electronic coherence time. A broad range of vibrational modes couple to the electronic subsystem, arising from inorganic and organic components. The simulations reveal the atomistic mechanisms underlying the enhancement of the excited-state lifetime achieved by the perovskite passivation, rationalize the experimental results, and advance our understanding of charge-phonon dynamics in perovskite solar cells.
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Affiliation(s)
- Lihong Liu
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry, Beijing Normal University , Beijing 100875, China
| | - Wei-Hai Fang
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry, Beijing Normal University , Beijing 100875, China
| | - Run Long
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry, Beijing Normal University , Beijing 100875, China
| | - Oleg V Prezhdo
- Department of Chemistry, University of Southern California , Los Angeles, California 90089, United States
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19
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Li L, Kanai Y. Dependence of hot electron transfer on surface coverage and adsorbate species at semiconductor–molecule interfaces. Phys Chem Chem Phys 2018; 20:12986-12991. [DOI: 10.1039/c7cp07247c] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Developing a molecular-level understanding of how a hot electron transfer process can be enhanced at semiconductor–molecule interfaces is central to advancing various future technologies.
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Affiliation(s)
- Lesheng Li
- Department of Chemistry
- University of North Carolina at Chapel Hill
- Chapel Hill
- North Carolina 27599
- USA
| | - Yosuke Kanai
- Department of Chemistry
- University of North Carolina at Chapel Hill
- Chapel Hill
- North Carolina 27599
- USA
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20
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Wei Y, Li L, Fang W, Long R, Prezhdo OV. Weak Donor-Acceptor Interaction and Interface Polarization Define Photoexcitation Dynamics in the MoS 2/TiO 2 Composite: Time-Domain Ab Initio Simulation. NANO LETTERS 2017; 17:4038-4046. [PMID: 28586230 DOI: 10.1021/acs.nanolett.7b00167] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
To realize the full potential of transition metal dichalcogenides interfaced with bulk semiconductors for solar energy applications, fast photoinduced charge separation, and slow electron-hole recombination are needed. Using a combination of time-domain density functional theory with nonadiabatic molecular dynamics, we demonstrate that the key features of the electron transfer (ET), energy relaxation and electron-hole recombination in a MoS2-TiO2 system are governed by the weak van der Waals interfacial interaction and interface polarization. Electric fields formed at the interface allow charge separation to happen already during the photoexcitation process. Those electrons that still reside inside MoS2, transfer into TiO2 slowly and by the nonadiabatic mechanism, due to weak donor-acceptor coupling. The ET time depends on excitation energy, because the TiO2 state density grows with energy, increasing the nonadiabatic transfer rate, and because MoS2 sulfur atoms start to contribute to the photoexcited state at higher energies, increasing the coupling. The ET is slower than electron-phonon energy relaxation because the donor-acceptor coupling is weak, rationalizing the experimentally observed injection of primarily hot electrons. The weak van der Waals MoS2-TiO2 interaction ensures a long-lived charge separated state and a short electron-hole coherence time. The injection is promoted primarily by phonons within the 200-800 cm-1 range. Higher frequency modes are particularly important for the electron-hole recombinations, because they are able to accept large amounts of electronic energy. The predicted time scales for the forward and backward ET, and energy relaxation can be measured by time-resolved spectroscopies. The reported simulations generate a detailed time-domain atomistic description of the complex interplay of the charge and energy transfer processes at the MoS2/TiO2 interface that are of fundamental importance to photovoltaic and photocatalytic applications. The results suggest that even though the photogenerated charge-separated state is long-lived, the slower charge separation, compared to the electron-phonon energy relaxation, can present problems in practical applications.
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Affiliation(s)
- Yaqing Wei
- College of Chemistry, Key Laboratory of Theoretical and Computational Photochemistry of Ministry of Education, Beijing Normal University , Beijing, 100875, People's Republic of China
| | - Linqiu Li
- Department of Chemistry, University of Southern California , Los Angeles, California 90089, United States
| | - Weihai Fang
- College of Chemistry, Key Laboratory of Theoretical and Computational Photochemistry of Ministry of Education, Beijing Normal University , Beijing, 100875, People's Republic of China
| | - Run Long
- College of Chemistry, Key Laboratory of Theoretical and Computational Photochemistry of Ministry of Education, Beijing Normal University , Beijing, 100875, People's Republic of China
| | - Oleg V Prezhdo
- Department of Chemistry, University of Southern California , Los Angeles, California 90089, United States
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21
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Liu Y, Shao D, Bai X, Yang Z, Lin C, Shao C. Function of CN group in organic sensitizers: The first principle study. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2017; 179:227-232. [PMID: 28254705 DOI: 10.1016/j.saa.2017.01.054] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2016] [Revised: 01/17/2017] [Accepted: 01/24/2017] [Indexed: 06/06/2023]
Abstract
The cyano group (CN) of the acceptor in organic sensitizers plays an important role for highly efficient dye-sensitized solar cells. In this paper, three 5, 6-difluoro-2,1,3-benzothiadiazole (DFBTD) organic molecules with different number of CN units, named ME15, ME16 and ME17, were investigated by the density functional theory (DFT) and time-dependent DFT (TDDFT). We analyzed the CNs effects on the electronic structures, optical properties, adsorption modes and electron transfer and injection. The result shows that ME17 has the largest maximum absorption wavelength (λmax) among these new designed dyes due to the strong electron withdrawing ability of two CNs. In addition, CN greatly influence the adsorption modes of dye/TiO2 and electron injection mechanism. ME16 with one CN also has good optical absorption properties and its acceptor has the strongest coupling strength with the TiO2 semiconductor which is favorable for electron transfer and injection. Thus, we believe that the number of CN groups in acceptor should be moderate and one CN in D-A-π-A structure dyes may be the more appropriate focusing on the light harvesting ability, electron transfer and electron injection.
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Affiliation(s)
- Yun Liu
- State Key Laboratory of Heavy Oil Processing, Beijing Key Laboratory of Optical Detection Technology for Oil and Gas, and College of Science, China University of Petroleum, Beijing 102249, PR China
| | - Di Shao
- State Key Laboratory of Heavy Oil Processing, Beijing Key Laboratory of Optical Detection Technology for Oil and Gas, and College of Science, China University of Petroleum, Beijing 102249, PR China
| | - Xiaohui Bai
- State Key Laboratory of Heavy Oil Processing, Beijing Key Laboratory of Optical Detection Technology for Oil and Gas, and College of Science, China University of Petroleum, Beijing 102249, PR China
| | - Zhenqing Yang
- State Key Laboratory of Heavy Oil Processing, Beijing Key Laboratory of Optical Detection Technology for Oil and Gas, and College of Science, China University of Petroleum, Beijing 102249, PR China; Cavendish Laboratory, University of Cambridge, J. J. Thomson Avenue, Cambridge CB30HE, United Kingdom.
| | - Chundan Lin
- State Key Laboratory of Heavy Oil Processing, Beijing Key Laboratory of Optical Detection Technology for Oil and Gas, and College of Science, China University of Petroleum, Beijing 102249, PR China.
| | - Changjin Shao
- State Key Laboratory of Heavy Oil Processing, Beijing Key Laboratory of Optical Detection Technology for Oil and Gas, and College of Science, China University of Petroleum, Beijing 102249, PR China.
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22
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Li L, Wong JC, Kanai Y. Examining the Effect of Exchange-Correlation Approximations in First-Principles Dynamics Simulation of Interfacial Charge Transfer. J Chem Theory Comput 2017; 13:2634-2641. [DOI: 10.1021/acs.jctc.7b00183] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Lesheng Li
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
| | - Jian Cheng Wong
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
| | - Yosuke Kanai
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
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23
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Long R, Prezhdo OV, Fang W. Nonadiabatic charge dynamics in novel solar cell materials. WILEY INTERDISCIPLINARY REVIEWS-COMPUTATIONAL MOLECULAR SCIENCE 2017. [DOI: 10.1002/wcms.1305] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Run Long
- College of Chemistry, Key Laboratory of Theoretical & Computational Photochemistry of Ministry of Education Beijing Normal University Beijing P.R. China
| | - Oleg V. Prezhdo
- Department of Chemistry University of Southern California Los Angeles CA USA
| | - Weihai Fang
- College of Chemistry, Key Laboratory of Theoretical & Computational Photochemistry of Ministry of Education Beijing Normal University Beijing P.R. China
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24
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Long R, Casanova D, Fang WH, Prezhdo OV. Donor–Acceptor Interaction Determines the Mechanism of Photoinduced Electron Injection from Graphene Quantum Dots into TiO2: π-Stacking Supersedes Covalent Bonding. J Am Chem Soc 2017; 139:2619-2629. [DOI: 10.1021/jacs.6b09598] [Citation(s) in RCA: 109] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Run Long
- College of Chemistry, Key Laboratory of Theoretical & Computational Photochemistry of Ministry of Education, Beijing Normal University, Beijing, 100875, P. R. China
| | - David Casanova
- Kimika Fakultatea,
Euskal Herriko Unibertsitatea and Donostia International Physics Center, 20018 Donostia, Euskadi, Spain
- IKERBASQUE, Basque
Foundation for Science, 48013 Bilbao, Euskadi, Spain
| | - Wei-Hai Fang
- College of Chemistry, Key Laboratory of Theoretical & Computational Photochemistry of Ministry of Education, Beijing Normal University, Beijing, 100875, P. R. China
| | - Oleg V. Prezhdo
- Department
of Chemistry, University of Southern California, Los Angeles, California 90089, United States
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25
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Dynamics of charge at water-to-semiconductor interface: Case study of wet [0 0 1] anatase TiO2 nanowire. Chem Phys 2016. [DOI: 10.1016/j.chemphys.2016.08.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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26
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Hermann G, Tremblay JC. Ultrafast photoelectron migration in dye-sensitized solar cells: Influence of the binding mode and many-body interactions. J Chem Phys 2016; 145:174704. [PMID: 27825243 DOI: 10.1063/1.4966260] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
In the present contribution, the ultrafast photoinduced electron migration dynamics at the interface between an alizarin dye and an anatase TiO2 thin film is investigated from first principles. Comparison between a time-dependent many-electron configuration interaction ansatz and a single active electron approach sheds light on the importance of many-body effects, stemming from uniquely defined initial conditions prior to photoexcitation. Particular emphasis is put on understanding the influence of the binding mode on the migration process. The dynamics is analyzed on the basis of a recently introduced toolset in the form of electron yields, electronic fluxes, and flux densities, to reveal microscopic details of the electron migration mechanism. From the many-body perspective, insight into the nature of electron-electron and hole-hole interactions during the charge transfer process is obtained. The present results reveal that the single active electron approach yields quantitatively and phenomenologically similar results as the many-electron ansatz. Furthermore, the charge migration processes in the dye-TiO2 model clusters with different binding modes exhibit similar mechanistic pathways but on largely different time scales.
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Affiliation(s)
- G Hermann
- Institut für Chemie und Biochemie, Freie Universität Berlin, Takustraße 3, 14195 Berlin, Germany
| | - J C Tremblay
- Institut für Chemie und Biochemie, Freie Universität Berlin, Takustraße 3, 14195 Berlin, Germany
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27
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Cai C, Zhai J, Bi G, Wu H. Electron energy transfer effect in Au NS/CH 3NH 3PbI 3-xCl x heterostructures via localized surface plasmon resonance coupling. OPTICS LETTERS 2016; 41:4297-4300. [PMID: 27628381 DOI: 10.1364/ol.41.004297] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Localized surface plasmon resonance coupling effects (LSPR) have attracted much attention due to their interesting properties. This Letter demonstrates significant photoluminescence (PL) enhancement in the Au NS/CH3NH3PbI3-xClx heterostructures via the LSPR coupling. The observed PL emission enhancement is mainly attributed to the hot electron energy transfer effect related to the LSPR coupling. For the energy transfer effect, photo-generated electrons will be directly extracted into Au SPs, rather than relaxed into exciton states. This energy transfer process is much faster than the diffusion and relaxation time of free electrons, and may provide new ideas on the design of high-efficiency solar cells and ultrafast response photodetectors.
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28
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Yuan C, Li L, Huang J, Ning Z, Sun L, Ågren H. Improving the Photocurrent in Quantum-Dot-Sensitized Solar Cells by Employing Alloy Pb xCd 1-xS Quantum Dots as Photosensitizers. NANOMATERIALS 2016; 6:nano6060097. [PMID: 28335226 PMCID: PMC5302620 DOI: 10.3390/nano6060097] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/06/2016] [Revised: 05/16/2016] [Accepted: 05/20/2016] [Indexed: 11/16/2022]
Abstract
Ternary alloy PbxCd1−xS quantum dots (QDs) were explored as photosensitizers for quantum-dot-sensitized solar cells (QDSCs). Alloy PbxCd1−xS QDs (Pb0.54Cd0.46S, Pb0.31Cd0.69S, and Pb0.24Cd0.76S) were found to substantially improve the photocurrent of the solar cells compared to the single CdS or PbS QDs. Moreover, it was found that the photocurrent increases and the photovoltage decreases when the ratio of Pb in PbxCd1−xS is increased. Without surface protecting layer deposition, the highest short-circuit current density reaches 20 mA/cm2 under simulated AM 1.5 illumination (100 mW/cm2). After an additional CdS coating layer was deposited onto the PbxCd1−xS electrode, the photovoltaic performance further improved, with a photocurrent of 22.6 mA/cm2 and an efficiency of 3.2%.
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Affiliation(s)
- Chunze Yuan
- Department of Theoretical Chemistry and Biology, School of Biotechnology, Royal Institute of Technology, 10691 Stockholm, Sweden.
| | - Lin Li
- Center of Molecular Devices, Department of Chemistry, School of Chemical Science and Engineering, Royal Institute of Technology, 10044 Stockholm, Sweden.
| | - Jing Huang
- Department of Theoretical Chemistry and Biology, School of Biotechnology, Royal Institute of Technology, 10691 Stockholm, Sweden.
| | - Zhijun Ning
- Department of Theoretical Chemistry and Biology, School of Biotechnology, Royal Institute of Technology, 10691 Stockholm, Sweden.
| | - Licheng Sun
- Center of Molecular Devices, Department of Chemistry, School of Chemical Science and Engineering, Royal Institute of Technology, 10044 Stockholm, Sweden.
| | - Hans Ågren
- Department of Theoretical Chemistry and Biology, School of Biotechnology, Royal Institute of Technology, 10691 Stockholm, Sweden.
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29
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Long R, Guo M, Liu L, Fang W. Nonradiative Relaxation of Photoexcited Black Phosphorus Is Reduced by Stacking with MoS2: A Time Domain ab Initio Study. J Phys Chem Lett 2016; 7:1830-1835. [PMID: 27132486 DOI: 10.1021/acs.jpclett.6b00757] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Black phosphorus (BP) is an appealing material for applications in electronics and optoelectronics because of its tunable direct band gap and high charge carrier mobility. For real optoelectronic device utilization, nonradiative electron-hole recombination should be slow because it constitutes a major pathway for charge and energy losses. Using time-domain density functional theory combined with nonadiabatic (NA) molecular dynamics, we show that nonradiative electron-hole recombination occurs within several tens of picoseconds in bilayer BP, agreeing well with experimental data. When a single layer of BP is stacked with monolayer MoS2, the recombination is reduced because of the increased band gap and reduced electron-phonon NA coupling compared to bilayer BP. The slow electron-phonon energy losses in BP-MoS2 van der Waals heterojunction relative to bilayer BP indicate that rationally stacking BP with other two-dimensional materials is an attractive route for designing novel and efficient photovoltaic materials.
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Affiliation(s)
- Run Long
- College of Chemistry, Key Laboratory of Theoretical & Computational Photochemistry of Ministry of Education, Beijing Normal University , Beijing, 100875, P. R. China
| | - Meng Guo
- Shandong Computer Science Center (National Supercomputer Center in Jinan) , Jinan, Shandong Province P. R. China , 250101
| | - Lihong Liu
- College of Chemistry, Key Laboratory of Theoretical & Computational Photochemistry of Ministry of Education, Beijing Normal University , Beijing, 100875, P. R. China
| | - Weihai Fang
- College of Chemistry, Key Laboratory of Theoretical & Computational Photochemistry of Ministry of Education, Beijing Normal University , Beijing, 100875, P. R. China
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30
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Li L, Kanai Y. Excited Electron Dynamics at Semiconductor-Molecule Type-II Heterojunction Interface: First-Principles Dynamics Simulation. J Phys Chem Lett 2016; 7:1495-1500. [PMID: 27041336 DOI: 10.1021/acs.jpclett.6b00436] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Excited electron dynamics at semiconductor-molecule interfaces is ubiquitous in various energy conversion technologies. However, a quantitative understanding of how molecular details influence the quantum dynamics of excited electrons remains a great scientific challenge because of the complex interplay of different processes with various time scales. Here, we employ first-principles electron dynamics simulations to investigate how molecular features govern the dynamics in a representative interface between the hydrogen-terminated Si(111) surface and a cyanidin molecule. Hot electron transfer to the chemisorbed molecule was observed but was short-lived on the molecule. Interfacial electron transfer to the chemisorbed molecule was found to be largely decoupled from hot electron relaxation within the semiconductor surface. While the hot electron relaxation was found to take place on a time scale of several hundred femtoseconds, the subsequent interfacial electron transfer was slower by an order of magnitude. At the same time, this secondary process of picosecond electron transfer is comparable in time scale to typical electron trapping into defect states in the energy gap.
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Affiliation(s)
- Lesheng Li
- Department of Chemistry, University of North Carolina at Chapel Hill , Chapel Hill, North Carolina 27599-3290, United States
| | - Yosuke Kanai
- Department of Chemistry, University of North Carolina at Chapel Hill , Chapel Hill, North Carolina 27599-3290, United States
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31
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Long R, Liu J, Prezhdo OV. Unravelling the Effects of Grain Boundary and Chemical Doping on Electron–Hole Recombination in CH3NH3PbI3 Perovskite by Time-Domain Atomistic Simulation. J Am Chem Soc 2016; 138:3884-90. [DOI: 10.1021/jacs.6b00645] [Citation(s) in RCA: 272] [Impact Index Per Article: 34.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Run Long
- College of Chemistry, Key Laboratory of Theoretical & Computational Photochemistry of Ministry of Education, Beijing Normal University, Beijing 100875, P. R. China
- School of Physics, Complex & Adaptive Systems Lab, University College Dublin, Dublin 4, Ireland
| | - Jin Liu
- Department
of Chemical Engineering, University of Rochester, Rochester, New York 14627, United States
| | - Oleg V. Prezhdo
- Department
of Chemistry, University of Southern California, Los Angeles, California 90089, United States
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32
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Abstract
Understanding photoinduced charge transfer from nanomaterials is essential to the many applications of these materials. This review summarizes recent progress in understanding charge transfer from quantum dots (QDs), an ideal model system for investigating fundamental charge transfer properties of low-dimensional quantum-confined nanomaterials. We first discuss charge transfer from QDs to weakly coupled acceptors within the framework of Marcus nonadiabatic electron transfer (ET) theory, focusing on the dependence of ET rates on reorganization energy, electronic coupling, and driving force. Because of the strong electron-hole interaction, we show that ET from QDs should be described by the Auger-assisted ET model, which is significantly different from ET between molecules or from bulk semiconductor electrodes. For strongly quantum-confined QDs on semiconductor surfaces, the coupling can fall within the strong coupling limit, in which case the donor-acceptor interaction and ET properties can be described by the Newns-Anderson model of chemisorption. We also briefly discuss recent progress in controlling charge transfer properties in quantum-confined nanoheterostructures through wavefunction engineering and multiple exciton dissociation. Finally, we identify a few key areas for further research.
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Affiliation(s)
- Haiming Zhu
- Department of Chemistry, Emory University, Atlanta, Georgia 30322;
| | - Ye Yang
- Department of Chemistry, Emory University, Atlanta, Georgia 30322;
| | - Kaifeng Wu
- Department of Chemistry, Emory University, Atlanta, Georgia 30322;
| | - Tianquan Lian
- Department of Chemistry, Emory University, Atlanta, Georgia 30322;
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33
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Long R, Prezhdo OV. Quantum Coherence Facilitates Efficient Charge Separation at a MoS2/MoSe2 van der Waals Junction. NANO LETTERS 2016; 16:1996-2003. [PMID: 26882202 DOI: 10.1021/acs.nanolett.5b05264] [Citation(s) in RCA: 128] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Two-dimensional transition metal dichalcogenides (MX2, M = Mo, W; X = S, Se) hold great potential in optoelectronics and photovoltaics. To achieve efficient light-to-electricity conversion, electron-hole pairs must dissociate into free charges. Coulomb interaction in MX2 often exceeds the charge transfer driving force, leading one to expect inefficient charge separation at a MX2 heterojunction. Experiments defy the expectation. Using time-domain density functional theory and nonadiabatic (NA) molecular dynamics, we show that quantum coherence and donor-acceptor delocalization facilitate rapid charge transfer at a MoS2/MoSe2 interface. The delocalization is larger for electron than hole, resulting in longer coherence and faster transfer. Stronger NA coupling and higher acceptor state density accelerate electron transfer further. Both electron and hole transfers are subpicosecond, which is in agreement with experiments. The transfers are promoted primarily by the out-of-plane Mo-X modes of the acceptors. Lighter S atoms, compared to Se, create larger NA coupling for electrons than holes. The relatively slow relaxation of the "hot" hole suggests long-distance bandlike transport, observed in organic photovoltaics. The electron-hole recombination is notably longer across the MoS2/MoSe2 interface than in isolated MoS2 and MoSe2, favoring long-lived charge separation. The atomistic, time-domain studies provide valuable insights into excitation dynamics in two-dimensional transition metal dichalcogenides.
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Affiliation(s)
- Run Long
- College of Chemistry, Key Laboratory of Theoretical and Computational Photochemistry of Ministry of Education, Beijing Normal University , Beijing, 100875, People's Republic of China
- School of Physics and Complex and Adaptive Systems Lab, University College Dublin , Dublin 4, Ireland
| | - Oleg V Prezhdo
- Department of Chemistry, University of Southern California , Los Angeles, California 90089, United States
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34
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Guiglion P, Berardo E, Butchosa C, Wobbe MCC, Zwijnenburg MA. Modelling materials for solar fuel synthesis by artificial photosynthesis; predicting the optical, electronic and redox properties of photocatalysts. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2016; 28:074001. [PMID: 26808228 DOI: 10.1088/0953-8984/28/7/074001] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
In this mini-review, we discuss what insight computational modelling can provide into the working of photocatalysts for solar fuel synthesis and how calculations can be used to screen for new promising materials for photocatalytic water splitting and carbon dioxide reduction. We will extensively discuss the different relevant (material) properties and the computational approaches (DFT, TD-DFT, GW/BSE) available to model them. We illustrate this with examples from the literature, focussing on polymeric and nanoparticle photocatalysts. We finish with a perspective on the outstanding conceptual and computational challenges.
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Affiliation(s)
- Pierre Guiglion
- Department of Chemistry, University College London, 20 Gordon street, London WC1H 0AJ, UK
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35
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Long R, Fang W, Akimov AV. Nonradiative Electron--Hole Recombination Rate Is Greatly Reduced by Defects in Monolayer Black Phosphorus: Ab Initio Time Domain Study. J Phys Chem Lett 2016; 7:653-659. [PMID: 26821943 DOI: 10.1021/acs.jpclett.6b00001] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
We report ab initio time-domain simulations of nonradiative electron-hole recombination and electronic dephasing in ideal and defect-containing monolayer black phosphorus (MBP). Our calculations predict that the presence of phosphorus divacancy in MBP (MBP-DV) substantially reduces the nonradiative recombination rate, with time scales on the order of 1.57 ns. The luminescence line width in ideal MBP of 150 meV is 2.5 times larger than MBP-DV at room temperature, and is in excellent agreement with experiment. We find that the electron-hole recombination in ideal MBP is driven by the 450 cm(-1) vibrational mode, whereas the recombination in the MBP-DV system is driven by a broad range of vibrational modes. The reduced electron-phonon coupling and increased bandgap in MBP-DV rationalize slower recombination in this material, suggesting that electron-phonon energy losses in MBP can be minimized by creating suitable defects in semiconductor device material.
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Affiliation(s)
- Run Long
- College of Chemistry, Key Laboratory of Theoretical & Computational Photochemistry of Ministry of Education, Beijing Normal University , Beijing, 100875, P. R. China
| | - Weihai Fang
- College of Chemistry, Key Laboratory of Theoretical & Computational Photochemistry of Ministry of Education, Beijing Normal University , Beijing, 100875, P. R. China
| | - Alexey V Akimov
- Department of Chemistry, Natural Sciences Complex, State University of New York at Buffalo , Buffalo, New York 14260-3000, United States
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Reeves KG, Schleife A, Correa AA, Kanai Y. Role of Surface Termination on Hot Electron Relaxation in Silicon Quantum Dots: A First-Principles Dynamics Simulation Study. NANO LETTERS 2015; 15:6429-6433. [PMID: 26331672 DOI: 10.1021/acs.nanolett.5b01707] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The role of surface termination on phonon-mediated relaxation of an excited electron in quantum dots was investigated using first-principles simulations. The surface terminations of a silicon quantum dot with hydrogen and fluorine atoms lead to distinctively different relaxation behaviors, and the fluorine termination shows a nontrivial relaxation process. The quantum confined electronic states are significantly affected by the surface of the quantum dot, and we find that a particular electronic state dictates the relaxation behavior through its infrequent coupling to neighboring electronic states. Dynamical fluctuation of this electronic state results in a slow shuttling behavior within the manifold of unoccupied electronic states, controlling the overall dynamics of the excited electron with its characteristic frequency of this shuttling behavior. The present work revealed a unique role of surface termination, dictating the hot electron relaxation process in quantum-confined systems in the way that has not been considered previously.
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Affiliation(s)
- Kyle G Reeves
- Department of Chemistry, University of North Carolina at Chapel Hill , Chapel Hill, North Carolina 27514, United States
| | - André Schleife
- Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign , Champaign, Illinois 61820, United States
| | - Alfredo A Correa
- Condensed Matter and Materials Division, Lawrence Livermore National Laboratory , Livermore, California 94550, United States
| | - Yosuke Kanai
- Department of Chemistry, University of North Carolina at Chapel Hill , Chapel Hill, North Carolina 27514, United States
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37
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Liu J, Kilina SV, Tretiak S, Prezhdo OV. Ligands Slow Down Pure-Dephasing in Semiconductor Quantum Dots. ACS NANO 2015; 9:9106-9116. [PMID: 26284384 DOI: 10.1021/acsnano.5b03255] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
It is well-known experimentally and theoretically that surface ligands provide additional pathways for energy relaxation in colloidal semiconductor quantum dots (QDs). They increase the rate of inelastic charge-phonon scattering and provide trap sites for the charges. We show that, surprisingly, ligands have the opposite effect on elastic electron-phonon scattering. Our simulations demonstrate that elastic scattering slows down in CdSe QDs passivated with ligands compared to that in bare QDs. As a result, the pure-dephasing time is increased, and the homogeneous luminescence line width is decreased in the presence of ligands. The lifetime of quantum superpositions of single and multiple excitons increases as well, providing favorable conditions for multiple excitons generation (MEG). Ligands reduce the pure-dephasing rates by decreasing phonon-induced fluctuations of the electronic energy levels. Surface atoms are most mobile in QDs, and therefore, they contribute greatly to the electronic energy fluctuations. The mobility is reduced by interaction with ligands. A simple analytical model suggests that the differences between the bare and passivated QDs persist for up to 5 nm diameters. Both low-frequency acoustic and high-frequency optical phonons participate in the dephasing processes in bare QDs, while low-frequency acoustic modes dominate in passivated QDs. The theoretical predictions regarding the pure-dephasing time, luminescence line width, and MEG can be verified experimentally by studying QDs with different surface passivation.
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Affiliation(s)
- Jin Liu
- Department of Chemical Engineering, University of Rochester , Rochester, New York 14627, United States
| | - Svetlana V Kilina
- Department of Chemistry, North Dakota State University , Fargo, North Dakota 58108, United States
| | - Sergei Tretiak
- Los Alamos National Laboratory , Los Alamos, New Mexico 87545, United States
| | - Oleg V Prezhdo
- Department of Chemistry, University of Southern California , Los Angeles, California 90089, United States
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38
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Trivedi DJ, Prezhdo OV. Decoherence Allows Model Reduction in Nonadiabatic Dynamics Simulations. J Phys Chem A 2015. [PMID: 26221974 DOI: 10.1021/acs.jpca.5b05869] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A nonadiabatic (NA) molecular dynamics (MD) simulation requires calculation of NA coupling matrix elements, the number of which scales as a square of the number of basis states. The basis size can be huge in studies of nanoscale materials, and calculation of the NA couplings can present a significant bottleneck. A quantum-classical approximation, NAMD overestimates coherence in the quantum, electronic subsystem, requiring decoherence correction. Generally, decoherence times decrease with increasing energy separation between pairs of states forming coherent superpositions. Since rapid decoherence stops quantum dynamics, one expects that decoherence-corrected NAMD can eliminate the need for calculation of NA couplings between energetically distant states, notably reducing the computational cost. Considering several types of dynamics in a semiconductor quantum dot, we demonstrate that indeed, decoherence allows one to reduce the number of needed NA coupling matrix elements. If the energy levels are spaced closer than 0.1 eV, one obtains good results while including only three nearest-neighbor couplings, and in some cases even with just the first nearest-neighbor coupling scheme. If the energy levels are spaced by about 0.4 eV, the nearest-neighbor model fails, while three or more nearest-neighbor schemes also provide good results. In comparison, the results of NAMD simulation without decoherence vary continuously with changes in the number of NA couplings. Thus, decoherence effects induced by coupling to a quantum-mechanical environment not only provide the physical mechanism for NAMD trajectory branding and improve the accuracy of NAMD simulations, but also afford significant computational savings.
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Affiliation(s)
- Dhara J Trivedi
- †Department of Physics and Astronomy, University of Rochester, Rochester, New York 14627, United States
| | - Oleg V Prezhdo
- ‡Department of Chemistry, University of Southern California, Los Angeles, California 90089, United States
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39
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Long R, Prezhdo OV. Time-Domain Ab Initio Analysis of Excitation Dynamics in a Quantum Dot/Polymer Hybrid: Atomistic Description Rationalizes Experiment. NANO LETTERS 2015; 15:4274-4281. [PMID: 26061416 DOI: 10.1021/nl5046268] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Hybrid organic/inorganic polymer/quantum dot (QD) solar cells are an attractive alternative to the traditional cells. The original, simple models postulate that one-dimensional polymers have continuous energy levels, while zero-dimensional QDs exhibit atom-like electronic structure. A realistic, atomistic viewpoint provides an alternative description. Electronic states in polymers are molecule-like: finite in size and discrete in energy. QDs are composed of many atoms and have high, bulk-like densities of states. We employ ab initio time-domain simulation to model the experimentally observed ultrafast photoinduced dynamics in a QD/polymer hybrid and show that an atomistic description is essential for understanding the time-resolved experimental data. Both electron and hole transfers across the interface exhibit subpicosecond time scales. The interfacial processes are fast due to strong electronic donor-acceptor, as evidenced by the densities of the photoexcited states which are delocalized between the donor and the acceptor. The nonadiabatic charge-phonon coupling is also strong, especially in the polymer, resulting in rapid energy losses. The electron transfer from the polymer is notably faster than the hole transfer from the QD, due to a significantly higher density of acceptor states. The stronger molecule-like electronic and charge-phonon coupling in the polymer rationalizes why the electron-hole recombination inside the polymer is several orders of magnitude faster than in the QD. As a result, experiments exhibit multiple transfer times for the long-lived hole inside the QD, ranging from subpicoseconds to nanoseconds. In contrast, transfer of the short-lived electron inside the polymer does not occur beyond the first picosecond. The energy lost by the hole on its transit into the polymer is accommodated by polymer's high-frequency vibrations. The energy lost by the electron injected into the QD is accommodated primarily by much lower-frequency collective and QD modes. The electron dynamics is exponential, whereas evolution of the injected hole through the low density manifold of states of the polymer is highly nonexponential. The time scale of the electron-hole recombination at the interface is intermediate between those in pristine polymer and QD and is closer to that in the polymer. The detailed atomistic insights into the photoinduced charge and energy dynamics at the polymer/QD interface provide valuable guidelines for optimization of solar light harvesting and photovoltaic efficiency in modern nanoscale materials.
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Affiliation(s)
| | - Oleg V Prezhdo
- §Department of Chemistry, University of Southern California, Los Angeles, California 90089, United States
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40
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Gao S. Nonlinear response of metal nanoparticles: Double plasmon excitation and electron transfer. J Chem Phys 2015; 142:234701. [DOI: 10.1063/1.4922490] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Affiliation(s)
- Shiwu Gao
- Beijing Computational Science Research Center, Zhongguancun Software Park II, 100094, Beijing, China
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41
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Wang L, Long R, Prezhdo OV. Time-Domain Ab Initio Modeling of Photoinduced Dynamics at Nanoscale Interfaces. Annu Rev Phys Chem 2015; 66:549-79. [DOI: 10.1146/annurev-physchem-040214-121359] [Citation(s) in RCA: 107] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Linjun Wang
- Department of Chemistry, University of Southern California, Los Angeles, California 90089-0482;
- Department of Chemistry, University of Rochester, Rochester, New York 14627
| | - Run Long
- School of Physics and Complex & Adaptive Systems Laboratory, University College Dublin, Belfield, Dublin 4, Ireland
| | - Oleg V. Prezhdo
- Department of Chemistry, University of Southern California, Los Angeles, California 90089-0482;
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42
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Feng HL, Wu WQ, Rao HS, Wan Q, Li LB, Kuang DB, Su CY. Three-dimensional TiO2/ZnO hybrid array as a heterostructured anode for efficient quantum-dot-sensitized solar cells. ACS APPLIED MATERIALS & INTERFACES 2015; 7:5199-5205. [PMID: 25679232 DOI: 10.1021/am507983y] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The development of a novel nanoarray photoanode with a heterostructure on a transparent conducting oxide substrate provides a promising scheme to fabricate efficient energy conversion devices. Herein, we successfully synthesize the vertically aligned hierarchical TiO2 nanowire/ZnO nanorod or TiO2 nanowire/ZnO nanosheet hybrid arrays, which are proven to be excellent anode candidates for superior light utilization. Consequently, the quantum-dot-sensitized solar cells based on such hybrid arrays exhibit an impressive power conversion efficiency (PCE) under AM 1.5G one sun illumination with improved short-circuit current density (JSC) and fill factor compared to pristine TiO2 nanowire arrays. Combined with the chemical-bath-deposited Cu2S counter electrode, the eventual PCE can be further optimized to as high as 4.57% for CdS/CdSe co-sensitized quantum dot solar cells.
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Affiliation(s)
- Hao-Lin Feng
- MOE Key Laboratory of Bioinorganic and Synthetic Chemistry, Lehn Institute of Functional Materials, School of Chemistry and Chemical Engineering, Sun Yat-Sen University , Guangzhou 510275, P. R. China
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43
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Kaledin AL, Lian T, Hill CL, Musaev DG. A Hybrid Quantum Mechanical Approach: Intimate Details of Electron Transfer between Type-I CdSe/ZnS Quantum Dots and an Anthraquinone Molecule. J Phys Chem B 2015; 119:7651-8. [PMID: 25604315 DOI: 10.1021/jp511935z] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
We report a hybrid computational approach to calculate electron transfer between a type-I CdSe/ZnS core/shell quantum dot (QD) with a varying shell thickness and the functionalized anthraquinone (AQ) molecule. This novel approach combines the traditional electron/hole confinement theory in the effective mass approximation for the QD and molecular orbital theory for the AQ molecule. In the present study, the QD's electron and hole envelope wave functions are solutions of the effective-mass Schrödinger equation, and the AQ wave function is obtained at the density functional level. Electron-transfer rate calculations are based on Marcus's theory with the coupling strength computed according to an one-electron orbital perturbation model. We show that in a heptane solution, the LUMO of AQ and the 1Se electron orbital of QD are involved in the charge separation (CS) process. The charge recombination (CR) process, on the other hand, occurs from the singly occupied molecular orbital of the AQ radical (which corresponds to the LUMO in AQ) to a trapped hole state of the QD within the band gap. The calculations support previously reported interpretations of the role of the ZnS shell as a hindrance in the CS and CR process.
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Affiliation(s)
- Alexey L Kaledin
- §Cherry L. Emerson Center for Scientific Computation and †Department of Chemistry, Emory University, 1515 Dickey Drive, Atlanta, Georgia 30322, United States
| | - Tianquan Lian
- §Cherry L. Emerson Center for Scientific Computation and †Department of Chemistry, Emory University, 1515 Dickey Drive, Atlanta, Georgia 30322, United States
| | - Craig L Hill
- §Cherry L. Emerson Center for Scientific Computation and †Department of Chemistry, Emory University, 1515 Dickey Drive, Atlanta, Georgia 30322, United States
| | - Djamaladdin G Musaev
- §Cherry L. Emerson Center for Scientific Computation and †Department of Chemistry, Emory University, 1515 Dickey Drive, Atlanta, Georgia 30322, United States
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44
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Jain K, Kaniyankandy S, Kishor S, Josefsson I, Ghosh HN, Singh KS, Mookerjee S, Odelius M, Ramaniah LM. Density functional investigation and some optical experiments on dye-sensitized quantum dots. Phys Chem Chem Phys 2015; 17:28683-96. [DOI: 10.1039/c5cp03816b] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Dye-sensitized quantum dots (QDs) are promising candidates for dye-sensitized solar cells (DSSCs).
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Affiliation(s)
- Kalpna Jain
- Department of Physics
- D. J. College
- Baraut
- India
| | | | | | - Ida Josefsson
- Department of Physics
- Stockholm University
- AlbaNova University Center
- Sweden
| | | | | | | | - Michael Odelius
- Department of Physics
- Stockholm University
- AlbaNova University Center
- Sweden
| | - Lavanya M. Ramaniah
- High Pressure and Synchrotron Radiation Physics Divison
- Physics Group
- Bhabha Atomic Research Centre
- Mumbai 400085
- India
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45
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Azpiroz JM, Ugalde JM, Etgar L, Infante I, De Angelis F. The effect of TiO2 surface on the electron injection efficiency in PbS quantum dot solar cells: a first-principles study. Phys Chem Chem Phys 2015; 17:6076-86. [DOI: 10.1039/c4cp04976d] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
We present a density functional theory (DFT) study aimed at understanding the injection and recombination processes that occur at the interface between PbS Quantum Dots and different TiO2 surfaces.
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Affiliation(s)
- Jon M. Azpiroz
- Kimika Fakultatea
- Euskal Herriko Unibertsitatea (UPV/EHU)
- and Donostia International Physics Center (DIPC)
- 20080 Donostia
- Spain
| | - Jesus M. Ugalde
- Kimika Fakultatea
- Euskal Herriko Unibertsitatea (UPV/EHU)
- and Donostia International Physics Center (DIPC)
- 20080 Donostia
- Spain
| | - Lioz Etgar
- Institute of Chemistry
- The Hebrew University of Jerusalem
- Casali Center for Applied Chemistry
- Jerusalem
- Israel
| | - Ivan Infante
- Kimika Fakultatea
- Euskal Herriko Unibertsitatea (UPV/EHU)
- and Donostia International Physics Center (DIPC)
- 20080 Donostia
- Spain
| | - Filippo De Angelis
- Computational Laboratory for Hybrid/Organic Photovoltaics (CLHYO)
- Istituto CNR di Scienze e Tecnologie Molecolari (ISTM-CNR)
- Perugia
- Italy
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46
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Long R, English NJ, Prezhdo OV. Minimizing Electron-Hole Recombination on TiO2 Sensitized with PbSe Quantum Dots: Time-Domain Ab Initio Analysis. J Phys Chem Lett 2014; 5:2941-6. [PMID: 26278240 DOI: 10.1021/jz5013627] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
TiO2 sensitized with quantum dots (QDs) gives efficient photovoltaic and photocatalytic systems due to high stability and large absorption cross sections of QDs and rapid photoinduced charge separation at the interface. The yields of the light-induced processes are limited by electron-hole recombination that also occurs at the interface. We combine ab initio nonadiabatic molecular dynamics with analytic theory to investigate the experimentally studied charge recombination at the PbSe QD-TiO2 interface. The time-domain atomistic simulation directly mimics the laser experiment and generates important details of the recombination mechanism. The process occurs due to coupling of the electronic subsystem to polar optical modes of the TiO2 surface. The inelastic electron-phonon scattering happens on a picosecond time scale, while the elastic scattering takes 40 fs. Counter to expectations, the donor-acceptor bonding strengthens at an elevated temperature. An analytic theory extends the simulation results to larger QDs and longer QD-TiO2 bridges. It shows that the electron-hole recombination rate decreases significantly for longer bridges and larger dots and that the main effect arises due to reduced donor-acceptor coupling rather than changes in the donor-acceptor energy gap. The study indicates that by varying QD size or ligands one can reduce charge losses while still maintaining efficient charge separation, providing design principles for optimizing solar cell design and increasing photon-to-electron conversion efficiencies.
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Affiliation(s)
- Run Long
- ‡Department of Chemistry, University of Southern California, 3620 McClintock Avenue, Los Angeles, California 90089, United States
| | | | - Oleg V Prezhdo
- ‡Department of Chemistry, University of Southern California, 3620 McClintock Avenue, Los Angeles, California 90089, United States
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47
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Huang S, Kilin DS. Charge Transfer, Luminescence, and Phonon Bottleneck in TiO2 Nanowires Computed by Eigenvectors of Liouville Superoperator. J Chem Theory Comput 2014; 10:3996-4005. [DOI: 10.1021/ct5004093] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Affiliation(s)
- Shuping Huang
- Department of Chemistry, University of South Dakota, Vermillion, South Dakota 57069, United States
| | - Dmitri S. Kilin
- Department of Chemistry, University of South Dakota, Vermillion, South Dakota 57069, United States
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48
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Huang S, Inerbaev TM, Kilin DS. Excited State Dynamics of Ru10 Cluster Interfacing Anatase TiO2(101) Surface and Liquid Water. J Phys Chem Lett 2014; 5:2823-2829. [PMID: 26278085 DOI: 10.1021/jz501221k] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Charge transfer dynamics at the interface of supported metal nanocluster and liquid water by GGA+U calculations combined with density matrix formalism is considered. The Ru10 cluster introduces new states into the band gap of TiO2 surface, narrows the band gap of TiO2, and enhances the absorption strength. The H2O adsorption significantly enhances the intensity of photon absorption, which is due to the formation of Ti-O(water) and Ru-O(water) bonds at the interfaces. The Ru10 cluster promotes the dissociation of water, facilitates charge transfer, and increases the relaxation rates of holes and electrons. We expect that our results are helpful in understanding basic processes contributing to photoelectrochemical water splitting.
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Affiliation(s)
- Shuping Huang
- †Department of Chemistry, University of South Dakota, Vermillion, South Dakota 57069, United States
| | - Talgat M Inerbaev
- ‡L. N. Gumilyov Eurasian National University, Mirzoyan str., 2, Astana 010008, Kazakhstan
| | - Dmitri S Kilin
- †Department of Chemistry, University of South Dakota, Vermillion, South Dakota 57069, United States
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49
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Liu Z, Guo K, Han J, Li Y, Cui T, Wang B, Ya J, Zhou C. Dendritic TiO2 /ln2 S3 /AgInS2 trilaminar core-shell branched nanoarrays and the enhanced activity for photoelectrochemical water splitting. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2014; 10:3153-3161. [PMID: 24700510 DOI: 10.1002/smll.201400622] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2014] [Revised: 03/19/2014] [Indexed: 06/03/2023]
Abstract
Hierarchical TiO2 /ln2 S3 /AgInS2 trilaminar core-shell branched nanorod arrays (T-CS BNRs) have been fabricated directly on conducting glass substrates (FTO) via a facile, versatile and low-cost hydrothermal and successive ionic layer adsorption and reaction (SILAR) for photoelectrochemical (PEC) water splitting. On the basis of optimal thickness of AgInS2 shell, such TiO2 /ln2 S3 /AgInS2 T-CS BNRs exhibit a higher photocatalytic activity, the photocurrent density and efficiency for hydrogen generation are up to 22.13 mA·cm(-2) and 14.83%, which is, to the best of our knowledge, the highest value ever reported for similar nanostructures. The trilaminar architecture is able to suppress carrier recombination and increase electron collection efficiency via (i) increasing the photon absorption through the lager specific surface area of TiO2 BNRs and a sensitizer layer (AgInS2 ), (ii) a buffer layer (ln2 S3 ), (iii) a better energy level alignment.
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Affiliation(s)
- Zhifeng Liu
- School of Materials Science and Engineering, Tianjin Chengjian University, Tianjin, 300384, P. R. China
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50
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An overview of nonadiabatic dynamics simulations methods, with focus on the direct approach versus the fitting of potential energy surfaces. Theor Chem Acc 2014. [DOI: 10.1007/s00214-014-1526-1] [Citation(s) in RCA: 102] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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