1
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Di Liberto G, Tosoni S. Stable, while Still Active? A DFT Study of Cu, Ag, and Au Single Atoms at the C 3N 4/TiO 2 Interface. Chemphyschem 2024; 25:e202400378. [PMID: 38726548 DOI: 10.1002/cphc.202400378] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2024] [Revised: 05/08/2024] [Indexed: 06/21/2024]
Abstract
Hybrid DFT calculations are employed to compare the adsorption and stabilization of Cu, Ag, and Au atoms on graphitic C3N4 and on the heterojunction formed by g- C3N4 and TiO2. While Cu and Ag can be strongly chemisorbed in form of cations on g- C3N4, Au is only weakly physisorbed. On g- C3N4/TiO2, all coinage metal adatoms can be strongly chemisorbed, but, while Cu and Ag forms cations, Au form an Au- species. Ab Initio Molecular Dynamics simulations confirm that the metal adatoms on g-C3N4 are highly mobile at room temperature, while they remain confined in the interfacial spacing between C3N4 and TiO2 on the heterojunction, being both stably bound and reachable for the reactants in a catalytic cycle. Doping g- C3N4/TiO2 with metal single atoms permits thus to generate catalytic systems with tunable charge and chemical properties and improved stability with respect to bare C3N4. Moreover, the changes in the electronic structure of g- C3N4/TiO2 induced by the presence of the metal single atoms are beneficial also for photocatalytic applications.
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Affiliation(s)
- Giovanni Di Liberto
- Department of Materials Science, University of Milan-Bicocca, Via Roberto Cozzi 55, 20125, Milan, Italy
| | - Sergio Tosoni
- Department of Materials Science, University of Milan-Bicocca, Via Roberto Cozzi 55, 20125, Milan, Italy
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2
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Asadinamin M, Živković A, de Leeuw NH, Lewis SP. Role of Interfacial Morphology in Cu 2O/TiO 2 and Band Bending: Insights from Density Functional Theory. ACS APPLIED MATERIALS & INTERFACES 2024; 16:35781-35792. [PMID: 38922125 PMCID: PMC11247431 DOI: 10.1021/acsami.4c06081] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2024] [Revised: 06/07/2024] [Accepted: 06/10/2024] [Indexed: 06/27/2024]
Abstract
Photocatalysis, a promising solution to environmental challenges, relies on the generation and utilization of photogenerated charge carriers within photocatalysts. However, the recombination of these carriers often limits efficiency. Heterostructures, especially Cu2O/TiO2, have emerged as effective solutions to enhance charge separation. This study systematically explores the effect of interfacial morphologies on the band bending within Cu2O/TiO2 anatase heterostructures by employing density functional theory. Through this study, eight distinct interfaces are identified and analyzed, revealing a consistent staggered-type band alignment. Despite variations in band edge positions, systematic charge transfer from Cu2O to TiO2 is observed across all interfaces. The proposed band bending configurations would suggest enhanced charge separation and photocatalytic activity under ultraviolet illumination due to a Z-scheme configuration. This theoretical investigation provides valuable insights into the interplay between interfacial morphology, band bending, and charge transfer for advancing the understanding of fundamental electronic mechanisms in heterostructures.
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Affiliation(s)
- Mona Asadinamin
- Department
of Physics and Astronomy, University of
Georgia, Athens, Georgia 30602, United States
| | - Aleksandar Živković
- Department
of Earth Sciences, Utrecht University, Princetonlaan 8a, 3548CB Utrecht, The Netherlands
- Institute
of Inorganic Chemistry, Christian-Albrecht
University of Kiel, Otto-Hahn-Platz
10, 24118 Kiel, Germany
| | - Nora H. de Leeuw
- Department
of Earth Sciences, Utrecht University, Princetonlaan 8a, 3548CB Utrecht, The Netherlands
- School
of Chemistry, University of Leeds, LS2 9JT Leeds, U.K.
| | - Steven P. Lewis
- Department
of Physics and Astronomy, University of
Georgia, Athens, Georgia 30602, United States
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3
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Shimazaki T, Tachikawa M. Theoretical study of short-range exchange interaction based on semiconductor dielectric function model toward time-dependent dielectric density functional theory. J Chem Phys 2024; 161:014107. [PMID: 38949277 DOI: 10.1063/5.0207751] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2024] [Accepted: 06/12/2024] [Indexed: 07/02/2024] Open
Abstract
This study explores various models of semiconductor dielectric functions, with a specific emphasis on the large wavenumber spectrum and the derivation of the screened exchange interaction. Particularly, we discuss the short-range effect of the screened exchange potential. Our investigation reveals that the short-range effect originating from the high wavenumber spectrum is contingent upon the dielectric constant of the targeted system. To incorporate dielectric-dependent behaviors concerning the short-range aspect into the dielectric density functional theory (DFT) framework, we utilize the local Slater term and the Yukawa-type term, adjusting the ratio between these terms based on the dielectric constant. Additionally, we demonstrate the efficacy of the time-dependent dielectric DFT method in accurately characterizing the electronic structure of excited states in dyes and functional molecules. Several theoretical approaches have incorporated parameters dependent on the system to elucidate short-range exchange interactions. Our theoretical analysis and discussions will be useful for those studies.
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Affiliation(s)
- Tomomi Shimazaki
- Graduate School of Nanobioscience, Yokohama City University, 22-2 Seto, Kanazawa-Ku, Yokohama 236-0026, Japan
| | - Masanori Tachikawa
- Graduate School of Nanobioscience, Yokohama City University, 22-2 Seto, Kanazawa-Ku, Yokohama 236-0026, Japan
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4
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Hua L, Li Z. Ideal Vacuum-Based Efficient and High-Throughput Computational Screening of Type II Heterojunctions. ACS APPLIED MATERIALS & INTERFACES 2023. [PMID: 38019534 DOI: 10.1021/acsami.3c11082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2023]
Abstract
Heterojunctions featuring a type II band alignment play a crucial role in a wide range of devices, particularly in the realm of solar cells. However, the design of such heterojunctions with a specific type of band alignment poses a substantial challenge due to the immense number of potential combinations of bulk semiconductors and their relative orientations. In this study, we propose an efficient, high-throughput computational screening method tailored for heterojunctions. Our approach, using the ideal vacuum level as a reference energy, eliminates the need for explicit electronic structure calculations for junctions. Through this protocol, we identify 1041 type II heterojunctions out of 2692 structures constructed from 86 selected inorganic compounds with appropriate band gaps sourced from the Inorganic Crystal Structure Database. For potential application in solar cells, we assess these heterojunctions, and remarkably, 58 of them exhibit a power conversion efficiency (PCE) exceeding 15%, with 13 surpassing the 20% threshold. Test calculations with expensive interface models confirm the reliability of PCE predictions based on ideal vacuums. These predictions will be of benefit in assessing the material applicability for solar cell applications. Furthermore, the versatility of our proposed screening method extends beyond solar cells, making it a valuable theoretical design tool that can be applied to a wide range of heterojunction devices.
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Affiliation(s)
- Ling Hua
- Hefei National Research Center for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Zhenyu Li
- Key Laboratory of Precision and Intelligent Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, China
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5
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Varley JB, Ray KG, Lordi V. Dangling Bonds as Possible Contributors to Charge Noise in Silicon and Silicon-Germanium Quantum Dot Qubits. ACS APPLIED MATERIALS & INTERFACES 2023; 15:43111-43123. [PMID: 37651689 DOI: 10.1021/acsami.3c06725] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/02/2023]
Abstract
Spin qubits based on Si and Si1-xGex quantum dot architectures exhibit among the best coherence times of competing quantum computing technologies, yet they still suffer from charge noise that limit their qubit gate fidelities. Identifying the origins of these charge fluctuations is therefore a critical step toward improving Si quantum-dot-based qubits. Here, we use hybrid functional calculations to investigate possible atomistic sources of charge noise, focusing on charge trapping at Si and Ge dangling bonds (DBs). We evaluate the role of global and local environment in the defect levels associated with DBs in Si, Ge, and Si1-xGex alloys, and consider their trapping and excitation energies within the framework of configuration coordinate diagrams. We additionally consider the influence of strain and oxidation in charge-trapping energetics by analyzing Si and GeSi DBs in SiO2 and strained Si layers in typical Si1-xGex quantum dot heterostructures. Our results identify that Ge dangling bonds are more problematic charge-trapping centers both in typical Si1-xGex alloys and associated oxidation layers, and they may be exacerbated by compositional inhomogeneities. These results suggest the importance of alloy homogeneity and possible passivation schemes for DBs in Si-based quantum dot qubits and are of general relevance to mitigating possible trap levels in other Si, Ge, and Si1-xGex-based metal-oxide-semiconductor stacks and related devices.
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Affiliation(s)
- Joel B Varley
- Materials Science Division, Lawrence Livermore National Laboratory, Livermore, California 94550, United States
| | - Keith G Ray
- Materials Science Division, Lawrence Livermore National Laboratory, Livermore, California 94550, United States
| | - Vincenzo Lordi
- Materials Science Division, Lawrence Livermore National Laboratory, Livermore, California 94550, United States
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6
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Mallick B, Saha D, Datta A, Ganguly S. Noninvasive and Contactless Characterization of Electronic Properties at the Semiconductor/Dielectric Interface Using Optical Second-Harmonic Generation. ACS APPLIED MATERIALS & INTERFACES 2023; 15:38888-38900. [PMID: 37539844 DOI: 10.1021/acsami.3c04985] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/05/2023]
Abstract
Optical second-harmonic generation (SHG) is a reliable technique for probing material surface and interface characteristics. Here, we have demonstrated a non-destructive, contactless SHG-based semiconductor/dielectric interface characterization method to measure the conduction band offset and quantitatively evaluate charge densities at the interface in oxide and at the oxide surface. This technique extracts the interface-trapped charge type (donor/acceptor) and qualitatively analyzes the process-induced variation in interface states (Dit), oxide, and oxide surface state density. These qualitative and quantitative analyses provide us with a glimpse into the band bending. The metrology method is validated through a detailed characterization of the Si/HfO2 interface. An optical setup has been developed to monitor the time-dependent second-harmonic generation (TDSHG) from the semiconductor/oxide interface. The temporal characteristics of TDSHG are explained with its relationship to the filling of Dit and spatio-temporal trapping of photoexcited charge in oxide and at the oxide surface. A numerical solver, based on plausible carrier dynamics, is used to model the experimental data and to extract the electronic properties at the Si/HfO2 interface.
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Affiliation(s)
- Binit Mallick
- Department of Electrical Engineering, Indian Institute of Technology Bombay, Mumbai 400076, India
| | - Dipankar Saha
- Department of Electrical Engineering, Indian Institute of Technology Bombay, Mumbai 400076, India
| | - Anindya Datta
- Department of Electrical Engineering, Indian Institute of Technology Bombay, Mumbai 400076, India
- Department of Chemistry, Indian Institute of Technology Bombay, Mumbai 400076, India
| | - Swaroop Ganguly
- Department of Electrical Engineering, Indian Institute of Technology Bombay, Mumbai 400076, India
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7
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Wang D, Zhao T, Yu Y. In/Ga-Doped Si as Anodes for Si-Air Batteries with Restrained Self-Corrosion and Surface Passivation: A First-Principles Study. Molecules 2023; 28:molecules28093784. [PMID: 37175193 PMCID: PMC10180196 DOI: 10.3390/molecules28093784] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Revised: 04/23/2023] [Accepted: 04/26/2023] [Indexed: 05/15/2023] Open
Abstract
Silicon-air batteries (SABs) are attracting considerable attention owing to their high theoretical energy density and superior security. In this study, In and Ga were doped into Si electrodes to optimize the capability of Si-air batteries. Varieties of Si-In/SiO2 and Si-Ga/SiO2 atomic interfaces were built, and their properties were analyzed using density functional theory (DFT). The adsorption energies of the SiO2 passivation layer on In- and Ga-doped silicon electrodes were higher than those on pure Si electrodes. Mulliken population analysis revealed a change in the average number of charge transfers of oxygen atoms at the interface. Furthermore, the local device density of states (LDDOS) of the modified electrodes showed high strength in the interfacial region. Additionally, In and Ga as dopants introduced new energy levels in the Si/SiO2 interface according to the projected local density of states (PLDOS), thus reducing the band gap of the SiO2. Moreover, the I-V curves revealed that doping In and Ga into Si electrodes enhanced the current flow of interface devices. These findings provide a mechanistic explanation for improving the practical efficiency of silicon-air batteries through anode doping and provide insight into the design of Si-based anodes in air batteries.
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Affiliation(s)
- Dongxu Wang
- College of Physics Science and Technology, Kunming University, Kunming 650214, China
| | - Tingyu Zhao
- College of Physics Science and Technology, Kunming University, Kunming 650214, China
| | - Yingjian Yu
- College of Physics Science and Technology, Kunming University, Kunming 650214, China
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8
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Naito T, Kita Y, Shimazaki T, Tachikawa M. Decomposition analysis on the excitation behaviors of thiazolothiazole (TTz)-based dyes via the time-dependent dielectric density functional theory approach. RSC Adv 2022; 12:34685-34693. [PMID: 36545599 PMCID: PMC9717578 DOI: 10.1039/d2ra06454e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Accepted: 11/22/2022] [Indexed: 12/05/2022] Open
Abstract
Thiazolothiazole (TTz)-based materials have been attracting much attention because of their widespread applications. In this paper, we discuss the excited electronic behaviors of asymmetric TTz dyes in solvents based on the time-dependent dielectric density functional theory method. Based on dipole moment and charge distribution (population) analyses, we discuss large intramolecular electron transfers, which are triggered by photon excitations, toward the acceptor part of dyes. In addition, we explore the contributions of geometrical changes and solvent reorientations (reorganizations) to the solvatofluorochromic phenomena based on a decomposition technique. The decomposition analysis shows that the solvent reorientation effect mainly contributes to changes in the fluorescent spectra in response to solvents.
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Affiliation(s)
- Takumi Naito
- Graduate School of Nanobioscience, Yokohama City University22-2 Seto, Kanazawa-kuYokohama 236-0026Japan
| | - Yukiumi Kita
- Graduate School of Nanobioscience, Yokohama City University22-2 Seto, Kanazawa-kuYokohama 236-0026Japan
| | - Tomomi Shimazaki
- Graduate School of Nanobioscience, Yokohama City University22-2 Seto, Kanazawa-kuYokohama 236-0026Japan
| | - Masanori Tachikawa
- Graduate School of Nanobioscience, Yokohama City University22-2 Seto, Kanazawa-kuYokohama 236-0026Japan
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9
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Dardzinski D, Yu M, Moayedpour S, Marom N. Best practices for first-principles simulations of epitaxial inorganic interfaces. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2022; 34:233002. [PMID: 35193122 DOI: 10.1088/1361-648x/ac577b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Accepted: 02/22/2022] [Indexed: 06/14/2023]
Abstract
At an interface between two materials physical properties and functionalities may be achieved, which would not exist in either material alone. Epitaxial inorganic interfaces are at the heart of semiconductor, spintronic, and quantum devices. First principles simulations based on density functional theory (DFT) can help elucidate the electronic and magnetic properties of interfaces and relate them to the structure and composition at the atomistic scale. Furthermore, DFT simulations can predict the structure and properties of candidate interfaces and guide experimental efforts in promising directions. However, DFT simulations of interfaces can be technically elaborate and computationally expensive. To help researchers embarking on such simulations, this review covers best practices for first principles simulations of epitaxial inorganic interfaces, including DFT methods, interface model construction, interface structure prediction, and analysis and visualization tools.
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Affiliation(s)
- Derek Dardzinski
- Department of Materials Science and Engineering, Carnegie Mellon University, Pittsburgh, PA 15213, United States of America
| | - Maituo Yu
- Department of Materials Science and Engineering, Carnegie Mellon University, Pittsburgh, PA 15213, United States of America
| | - Saeed Moayedpour
- Department of Chemistry, Carnegie Mellon University, Pittsburgh, PA 15213, United States of America
| | - Noa Marom
- Department of Materials Science and Engineering, Carnegie Mellon University, Pittsburgh, PA 15213, United States of America
- Department of Chemistry, Carnegie Mellon University, Pittsburgh, PA 15213, United States of America
- Department of Physics, Carnegie Mellon University, Pittsburgh, PA 15213, United States of America
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10
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Vona C, Nabok D, Draxl C. Electronic Structure of (Organic‐)Inorganic Metal Halide Perovskites: The Dilemma of Choosing the Right Functional. ADVANCED THEORY AND SIMULATIONS 2021. [DOI: 10.1002/adts.202100496] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Affiliation(s)
- Cecilia Vona
- Institut für Physik and IRIS Adlershof Humboldt‐Universität zu Berlin 12489 Berlin Germany
- European Theoretical Spectroscopic Facility (ETSF)
| | - Dmitrii Nabok
- Institut für Physik and IRIS Adlershof Humboldt‐Universität zu Berlin 12489 Berlin Germany
- European Theoretical Spectroscopic Facility (ETSF)
| | - Claudia Draxl
- Institut für Physik and IRIS Adlershof Humboldt‐Universität zu Berlin 12489 Berlin Germany
- European Theoretical Spectroscopic Facility (ETSF)
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11
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Shimazaki T, Tachikawa M. A theoretical study on solvatofluorochromic asymmetric thiazolothiazole (TTz) dyes using dielectric-dependent density functional theory. Phys Chem Chem Phys 2021; 23:21078-21086. [PMID: 34523637 DOI: 10.1039/d1cp02047a] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
In this work, the excitation energies of asymmetric thiazolothizaole (TTz) dye molecules have been theoretically studied using dielectric-dependent density functional theory (DFT). In the dielectric-dependent DFT approach, the ratio (fraction) of the nonlocal Hartree exchange term incorporated into the DFT exchange-correlation functional is a system-dependent parameter, which is inversely proportional to the dielectric constant of the target material. The dielectric-dependent DFT method is closely related to the Coulomb hole and screened exchange (COHSEX) approximation in the GW method and therefore has been applied to crystalline systems with periodic boundary conditions, such as semiconductors and inorganic materials. By focusing on the solvatofluorochromic phenomena of asymmetric TTz dyes, we show that excitation energy calculations obtained from the dielectric-dependent DFT method can reproduce the corresponding experimental UV-vis absorption and emission spectra of dyes in solvents.
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Affiliation(s)
- Tomomi Shimazaki
- Department of Material System Science, Yokohama City University, 22-2 Seto, Kanazawa-ku, Yokohama, 236-0026, Japan.
| | - Masanori Tachikawa
- Department of Material System Science, Yokohama City University, 22-2 Seto, Kanazawa-ku, Yokohama, 236-0026, Japan.
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12
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Di Liberto G, Cipriano LA, Tosoni S, Pacchioni G. Rational Design of Semiconductor Heterojunctions for Photocatalysis. Chemistry 2021; 27:13306-13317. [PMID: 34264526 PMCID: PMC8518984 DOI: 10.1002/chem.202101764] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Indexed: 11/06/2022]
Abstract
Electronic structure calculations provide a useful complement to experimental characterization tools in the atomic-scale design of semiconductor heterojunctions for photocatalysis. The band alignment of the heterojunction is of fundamental importance to achieve an efficient charge carrier separation, so as to reduce electron/hole recombination and improve photoactivity. The accurate prediction of the offsets of valence and conduction bands in the constituent units is thus of key importance but poses several methodological and practical problems. In this Minireview we address some of these problems by considering selected examples of binary and ternary semiconductor heterojunctions and how these are determined at the level of density functional theory (DFT). The atomically precise description of the interface, the consequent charge polarization, the role of quantum confinement, the possibility to use facet engineering to determine a specific band alignment, are among the effects discussed, with particular attention to pros and cons of each one of these aspects. This analysis shows the increasingly important role of accurate electronic structure calculations to drive the design and the preparation of new interfaces with desired properties.
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Affiliation(s)
- Giovanni Di Liberto
- Dipartimento di Scienza dei MaterialiUniversità di Milano – BicoccaVia R. Cozzi 5520125MilanoItaly
| | - Luis A. Cipriano
- Dipartimento di Scienza dei MaterialiUniversità di Milano – BicoccaVia R. Cozzi 5520125MilanoItaly
| | - Sergio Tosoni
- Dipartimento di Scienza dei MaterialiUniversità di Milano – BicoccaVia R. Cozzi 5520125MilanoItaly
| | - Gianfranco Pacchioni
- Dipartimento di Scienza dei MaterialiUniversità di Milano – BicoccaVia R. Cozzi 5520125MilanoItaly
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13
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Di Liberto G, Pacchioni G. Band offset in semiconductor heterojunctions. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2021; 33:415002. [PMID: 34284370 DOI: 10.1088/1361-648x/ac1620] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Accepted: 07/20/2021] [Indexed: 06/13/2023]
Abstract
Semiconductor heterojunctions are widely applied in solid-state device applications, including semiconductor lasers, solar cells, and transistors. In photocatalysis they are of interest due to their capability to hinder charge carriers' recombination. A key role in the performance of heterojunctions is that of the alignment of the band edges of the two units composing the junction. In this work, we compare the performances of three widely applied approaches for the simulation of semiconductors heterostructures, based on density functional theory calculations with hybrid functionals. We benchmark the band offsets of ten semiconductors heterostructures for which experimental values are available: AlP/GaP, AlP/Si, AlAs/GaAs, AlAs/Ge, GaAs/Ge, GaP/Si, ZnSe/Ge, ZnSe/AlAs, ZnSe/GaAs, and TiO2/SrTiO3. The methods considered are (i) the alternating slabs junction (ASJ), (ii) the surface terminated junction (STJ), and (iii) the independent units (IU) approach. Moreover, two different ways to determine a common reference have been considered, (i) the plane averaged electrostatic potential, and (ii) the energy of the core levels. Advantages, drawbacks and overall performances of each method are discussed. The results suggest that the accuracy in the estimation of the band offsets is ∼0.2 eV when the ASJ method is applied. The STJ approach provides a similar accuracy, while the neglection of any interface effect, as in the IU method, provides only a qualitative estimate of the band offset and can result in significant deviations from the experiment.
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Affiliation(s)
- Giovanni Di Liberto
- Dipartimento di Scienza dei Materiali, Università di Milano-Bicocca, via R. Cozzi 55, 20125 Milano, Italy
| | - Gianfranco Pacchioni
- Dipartimento di Scienza dei Materiali, Università di Milano-Bicocca, via R. Cozzi 55, 20125 Milano, Italy
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14
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Kyrtsos A, Matsubara M, Bellotti E. Band offsets of Al xGa 1-xN alloys using first-principles calculations. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2020; 32:365504. [PMID: 32396144 DOI: 10.1088/1361-648x/ab922a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2020] [Accepted: 05/12/2020] [Indexed: 06/11/2023]
Abstract
First-principles calculations are employed for the study of the band offsets of AlxGa1-xN alloys, taking into account their composition and atomic configuration. Specifically, the band offsets are obtained using PBE, PBEsol, Heyd, Scuseria, and Ernzerhof (HSE), and modified Becke-Johnson calculations, comparing the results and discussing the advantages and disadvantages of each functional. The band alignments are performed using the branch point energies of the materials as their common reference level. HSE calculations predict a valence band offset of 0.9 eV between GaN and AlN. Regarding the alloys, a conduction band edge bowing parameter of 0.55 eV and a practically zero bowing for the valence band edge is predicted on average. The different atomic configurations affect mainly the valence band edges, where deviations from linearity by more than 0.1 eV are observed.
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Affiliation(s)
- Alexandros Kyrtsos
- Department of Electrical and Computer Engineering, Boston University, Boston, MA 02215, United States of America
| | - Masahiko Matsubara
- Department of Electrical and Computer Engineering, Boston University, Boston, MA 02215, United States of America
| | - Enrico Bellotti
- Department of Electrical and Computer Engineering, Boston University, Boston, MA 02215, United States of America
- Division of Materials Science and Engineering, Boston University, Boston, MA 02215, United States of America
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15
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Skelton JM, Gunn DSD, Metz S, Parker SC. Accuracy of Hybrid Functionals with Non-Self-Consistent Kohn-Sham Orbitals for Predicting the Properties of Semiconductors. J Chem Theory Comput 2020; 16:3543-3557. [PMID: 32369352 DOI: 10.1021/acs.jctc.9b01218] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Accurately modeling the electronic structure of materials is a persistent challenge to high-throughput screening. A promising means of balancing accuracy against computational cost is non-self-consistent calculations with hybrid density-functional theory, where the electronic band energies are evaluated using a hybrid functional from orbitals obtained with a less demanding (semi)local functional. We have quantified the performance of this technique for predicting the physical properties of 16 tetrahedral semiconductors with bandgaps from 0.2 to 5.5 eV. Provided the base functional predicts a nonmetallic electronic structure, bandgaps within 5% of the PBE0 and HSE06 gaps can be obtained with an order of magnitude reduction in computing time. The positions of the valence and conduction band extrema and the Fermi level are well reproduced, enabling calculation of the band dispersion, density of states, and dielectric properties using Fermi's Golden Rule. While the error in the non-self-consistent total energies is ∼50 meV atom-1, the energy-volume curves are reproduced accurately enough to obtain the equilibrium volume and bulk modulus with minimal error. We also test the dielectric-dependent scPBE0 functional and obtain bandgaps and dielectric constants to within 2.5% of the self-consistent results, which amounts to a significant improvement over self-consistent PBE0 for a similar computational cost. We identify cases where the non-self-consistent approach is expected to perform poorly and demonstrate that partial self-consistency provides a practical and efficient workaround. Finally, we perform proof-of-concept calculations on CoO and NiO to demonstrate the applicability of the technique to strongly correlated open-shell transition-metal oxides.
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Affiliation(s)
- Jonathan M Skelton
- Department of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom.,Department of Chemistry, University of Bath, Bath BA2 7AY, United Kingdom
| | - David S D Gunn
- STFC Daresbury Laboratory, Keckwick Ln., Daresbury, Warrington WA4 4AD, United Kingdom
| | - Sebastian Metz
- STFC Daresbury Laboratory, Keckwick Ln., Daresbury, Warrington WA4 4AD, United Kingdom.,Fraunhofer Institute for Solar Energy Systems ISE, Heidenhofstraße 2, 79110 Freiburg, Germany
| | - Stephen C Parker
- Department of Chemistry, University of Bath, Bath BA2 7AY, United Kingdom
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16
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Coutinho J, Markevich VP, Peaker AR. Characterisation of negative- Udefects in semiconductors. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2020; 32:323001. [PMID: 32182607 DOI: 10.1088/1361-648x/ab8091] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2020] [Accepted: 03/17/2020] [Indexed: 05/25/2023]
Abstract
This review aims at providing a retrospective, as well as a description of the state-of-the-art and future prospects regarding the theoretical and experimental characterisation of negative-Udefects in semiconductors. This is done by complementing the account with a description of the work that resulted in some of the most detailed, and yet more complex defect models in semiconductors. The essential physics underlying the negative-Ubehaviour is presented, including electronic correlation, electron-phonon coupling, disproportionation, defect transition levels and rates. Techniques for the analysis of the experimental data and modelling are also introduced, namely defect statistics, kinetics of carrier capture and emission, defect transformation, configuration coordinate diagrams and other tools. We finally include a showcase of several works that led to the identification of some of the most impacting negative-Udefects in group-IV and compound semiconductors.
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Affiliation(s)
- José Coutinho
- i3N, Department of Physics, University of Aveiro, Campus Santiago, 3810-193 Aveiro, Portugal
| | - Vladimir P Markevich
- Photon Science Institute, School of Electrical and Electronic Engineering, The University of Manchester, Manchester M13 9PL, United Kingdom
| | - Anthony R Peaker
- Photon Science Institute, School of Electrical and Electronic Engineering, The University of Manchester, Manchester M13 9PL, United Kingdom
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17
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Zhang M, Cui Z, Wang Y, Jiang H. Hybrid functionals with system‐dependent parameters: Conceptual foundations and methodological developments. WIRES COMPUTATIONAL MOLECULAR SCIENCE 2020. [DOI: 10.1002/wcms.1476] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Min‐Ye Zhang
- Beijing National Laboratory for Molecular Sciences College of Chemistry and Molecular Engineering, Peking University Beijing China
| | - Zhi‐Hao Cui
- Division of Chemistry and Chemical Engineering California Institute of Technology Pasadena California USA
| | - Yue‐Chao Wang
- Beijing National Laboratory for Molecular Sciences College of Chemistry and Molecular Engineering, Peking University Beijing China
| | - Hong Jiang
- Beijing National Laboratory for Molecular Sciences College of Chemistry and Molecular Engineering, Peking University Beijing China
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18
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Daelman N, Hegner FS, Rellán-Piñeiro M, Capdevila-Cortada M, García-Muelas R, López N. Quasi-degenerate states and their dynamics in oxygen deficient reducible metal oxides. J Chem Phys 2020; 152:050901. [PMID: 32035446 DOI: 10.1063/1.5138484] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
The physical and chemical properties of oxides are defined by the presence of oxygen vacancies. Experimentally, non-defective structures are almost impossible to achieve due to synthetic constraints. Therefore, it is crucial to account for vacancies when evaluating the characteristics of these materials. The electronic structure of oxygen-depleted oxides deeply differs from that of the native forms, in particular, of reducible metal oxides, where excess electrons can localize in various distinct positions. In this perspective, we present recent developments from our group describing the complexity of these defective materials that highlight the need for an accurate description of (i) intrinsic vacancies in polar terminations, (ii) multiple geometries and complex electronic structures with several states attainable at typical working conditions, and (iii) the associated dynamics for both vacancy diffusion and the coexistence of more than one electronic structure. All these aspects widen our current understanding of defects in oxides and need to be adequately introduced in emerging high-throughput screening methodologies.
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Affiliation(s)
- Nathan Daelman
- Institute of Chemical Research of Catalonia, ICIQ, The Barcelona Institute of Science and Technology, BIST, Av. Països Catalans 16, 43007 Tarragona, Spain
| | - Franziska Simone Hegner
- Institute of Chemical Research of Catalonia, ICIQ, The Barcelona Institute of Science and Technology, BIST, Av. Països Catalans 16, 43007 Tarragona, Spain
| | - Marcos Rellán-Piñeiro
- Institute of Chemical Research of Catalonia, ICIQ, The Barcelona Institute of Science and Technology, BIST, Av. Països Catalans 16, 43007 Tarragona, Spain
| | - Marçal Capdevila-Cortada
- Institute of Chemical Research of Catalonia, ICIQ, The Barcelona Institute of Science and Technology, BIST, Av. Països Catalans 16, 43007 Tarragona, Spain
| | - Rodrigo García-Muelas
- Institute of Chemical Research of Catalonia, ICIQ, The Barcelona Institute of Science and Technology, BIST, Av. Països Catalans 16, 43007 Tarragona, Spain
| | - Núria López
- Institute of Chemical Research of Catalonia, ICIQ, The Barcelona Institute of Science and Technology, BIST, Av. Països Catalans 16, 43007 Tarragona, Spain
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19
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Xu R, Lin N, Jia Z, Liu Y, Wang H, Yu Y, Zhao X. First principles study of Schottky barriers at Ga2O3(100)/metal interfaces. RSC Adv 2020; 10:14746-14752. [PMID: 35497154 PMCID: PMC9052123 DOI: 10.1039/c9ra09521g] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2019] [Accepted: 04/02/2020] [Indexed: 01/05/2023] Open
Abstract
A low Schottky barrier height (SBH) of metal–semiconductor contact is essential for achieving high performance electronic devices. Based on first principles calculations, we have comprehensively investigated the interfacial properties of β-Ga2O3 (100) with different metals including Mg, Ni, Cu, Pd and Pt. SBHs have been calculated via layered partial density of states (PDOS) and validated by visual wavefunctions. The results surprisingly show that Mg contact possesses the lowest SBH of 0.23 eV, while other SBHs range from 1.06 eV for Ni, 1.17 eV for Pd and 1.27 eV for Cu to 1.39 eV for Pt. This shows that SBHs of β-Ga2O3 are not fully dependent on metal work functions due to a Fermi level pinning effect. The tunneling barrier was also calculated via electrostatic potential with a 72.85% tunneling probability of the Mg/Ga2O3 interface. The present study will provide an insight into characteristics of Ga2O3/metal interfaces and give guidance for metal choice for Ga2O3 electronic devices. A low Schottky barrier height (SBH) of metal–semiconductor contact is essential for achieving high performance electronic devices.![]()
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Affiliation(s)
- Ran Xu
- State Key Lab of Crystal Materials
- Shandong University
- 250100 Jinan
- P. R. China
- State Key Laboratory of Superlattices and Microstructures
| | - Na Lin
- State Key Lab of Crystal Materials
- Shandong University
- 250100 Jinan
- P. R. China
- Department of Chemistry
| | - Zhitai Jia
- State Key Lab of Crystal Materials
- Shandong University
- 250100 Jinan
- P. R. China
| | - Yueyang Liu
- State Key Laboratory of Superlattices and Microstructures
- Institute of Semiconductors
- Chinese Academy of Sciences
- 100083 Beijing
- P. R. China
| | - Haoyuan Wang
- State Key Lab of Crystal Materials
- Shandong University
- 250100 Jinan
- P. R. China
| | - Yifei Yu
- State Key Lab of Crystal Materials
- Shandong University
- 250100 Jinan
- P. R. China
| | - Xian Zhao
- State Key Lab of Crystal Materials
- Shandong University
- 250100 Jinan
- P. R. China
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20
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Abstract
We determine the ionization potential (IP) and the electron affinity (EA) of liquid water together with the absolute redox level of the standard hydrogen electrode (SHE) by combining advanced electronic-structure calculations, ab initio molecular dynamics simulations, thermodynamic integration, and potential alignment at the water-vacuum interface. The calculated SHE level lies at 4.56 eV below the vacuum level, close to the experimental reference of 4.44 eV inferred by Trasatti. The band edges are determined through a hybrid functional designed to reproduce the band gap achieved with highly accurate GW calculations. Our analysis yields IP = 9.7 eV and EA = 0.8 eV, consistent with both photoemission spectra of liquid water and thermodynamical data for the hydrated electron.
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Affiliation(s)
- Francesco Ambrosio
- Chaire de Simulation à l'Echelle Atomique (CSEA) , Ecole Polytechnique Fédérale de Lausanne (EPFL) , CH-1015 Lausanne , Switzerland
| | - Zhendong Guo
- Chaire de Simulation à l'Echelle Atomique (CSEA) , Ecole Polytechnique Fédérale de Lausanne (EPFL) , CH-1015 Lausanne , Switzerland
| | - Alfredo Pasquarello
- Chaire de Simulation à l'Echelle Atomique (CSEA) , Ecole Polytechnique Fédérale de Lausanne (EPFL) , CH-1015 Lausanne , Switzerland
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21
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Navarrete-López AM, Rivera-Almazo M, Garza J, Vargas R. Importance of one-parameter hybrid exchange-correlation functionals in band gaps of transition metal and metalloid oxides. Theor Chem Acc 2018. [DOI: 10.1007/s00214-018-2222-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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22
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Gerosa M, Bottani CE, Di Valentin C, Onida G, Pacchioni G. Accuracy of dielectric-dependent hybrid functionals in the prediction of optoelectronic properties of metal oxide semiconductors: a comprehensive comparison with many-body GW and experiments. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2018; 30:044003. [PMID: 29087359 DOI: 10.1088/1361-648x/aa9725] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Understanding the electronic structure of metal oxide semiconductors is crucial to their numerous technological applications, such as photoelectrochemical water splitting and solar cells. The needed experimental and theoretical knowledge goes beyond that of pristine bulk crystals, and must include the effects of surfaces and interfaces, as well as those due to the presence of intrinsic defects (e.g. oxygen vacancies), or dopants for band engineering. In this review, we present an account of the recent efforts in predicting and understanding the optoelectronic properties of oxides using ab initio theoretical methods. In particular, we discuss the performance of recently developed dielectric-dependent hybrid functionals, providing a comparison against the results of many-body GW calculations, including G 0 W 0 as well as more refined approaches, such as quasiparticle self-consistent GW. We summarize results in the recent literature for the band gap, the band level alignment at surfaces, and optical transition energies in defective oxides, including wide gap oxide semiconductors and transition metal oxides. Correlated transition metal oxides are also discussed. For each method, we describe successes and drawbacks, emphasizing the challenges faced by the development of improved theoretical approaches. The theoretical section is preceded by a critical overview of the main experimental techniques needed to characterize the optoelectronic properties of semiconductors, including absorption and reflection spectroscopy, photoemission, and scanning tunneling spectroscopy (STS).
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Affiliation(s)
- M Gerosa
- Institute for Molecular Engineering, University of Chicago, Chicago, IL 60637, United States of America
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23
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Borlido P, Marques MAL, Botti S. Local Hybrid Density Functional for Interfaces. J Chem Theory Comput 2018; 14:939-947. [DOI: 10.1021/acs.jctc.7b00853] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Pedro Borlido
- Institut
für Festkörpertheorie und-optik, Friedrich-Schiller-Universität Jena and European Theoretical Spectroscopy Facility, Max-Wien-Platz 1, 07743 Jena, Germany
| | - Miguel A. L. Marques
- Institut
für Physik, Martin-Luther-Universität Halle-Wittenberg and European Theoretical Spectroscopy Facility, D-06099 Halle, Germany
| | - Silvana Botti
- Institut
für Festkörpertheorie und-optik, Friedrich-Schiller-Universität Jena and European Theoretical Spectroscopy Facility, Max-Wien-Platz 1, 07743 Jena, Germany
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24
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Zheng F, Pham HH, Wang LW. Effects of the c-Si/a-SiO 2 interfacial atomic structure on its band alignment: an ab initio study. Phys Chem Chem Phys 2017; 19:32617-32625. [PMID: 29192712 DOI: 10.1039/c7cp05879a] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The crystalline-Si/amorphous-SiO2 (c-Si/a-SiO2) interface is an important system used in many applications, ranging from transistors to solar cells. The transition region of the c-Si/a-SiO2 interface plays a critical role in determining the band alignment between the two regions. However, the question of how this interface band offset is affected by the transition region thickness and its local atomic arrangement is yet to be fully investigated. Here, by controlling the parameters of the classical Monte Carlo bond switching algorithm, we have generated the atomic structures of the interfaces with various thicknesses, as well as containing Si at different oxidation states. A hybrid functional method, as shown by our calculations to reproduce the GW and experimental results for bulk Si and SiO2, was used to calculate the electronic structure of the heterojunction. This allowed us to study the correlation between the interface band characterization and its atomic structures. We found that although the systems with different thicknesses showed quite different atomic structures near the transition region, the calculated band offset tended to be the same, unaffected by the details of the interfacial structure. Our band offset calculation agrees well with the experimental measurements. This robustness of the interfacial electronic structure to its interfacial atomic details could be another reason for the success of the c-Si/a-SiO2 interface in Si-based electronic applications. Nevertheless, when a reactive force field is used to generate the a-SiO2 and c-Si/a-SiO2 interfaces, the band offset significantly deviates from the experimental values by about 1 eV.
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Affiliation(s)
- Fan Zheng
- Joint Center for Artificial Photosynthesis and Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA.
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25
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Pham TA, Govoni M, Seidel R, Bradforth SE, Schwegler E, Galli G. Electronic structure of aqueous solutions: Bridging the gap between theory and experiments. SCIENCE ADVANCES 2017; 3:e1603210. [PMID: 28691091 PMCID: PMC5482551 DOI: 10.1126/sciadv.1603210] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2016] [Accepted: 04/28/2017] [Indexed: 05/31/2023]
Abstract
Predicting the electronic properties of aqueous liquids has been a long-standing challenge for quantum mechanical methods. However, it is a crucial step in understanding and predicting the key role played by aqueous solutions and electrolytes in a wide variety of emerging energy and environmental technologies, including battery and photoelectrochemical cell design. We propose an efficient and accurate approach to predict the electronic properties of aqueous solutions, on the basis of the combination of first-principles methods and experimental validation using state-of-the-art spectroscopic measurements. We present results of the photoelectron spectra of a broad range of solvated ions, showing that first-principles molecular dynamics simulations and electronic structure calculations using dielectric hybrid functionals provide a quantitative description of the electronic properties of the solvent and solutes, including excitation energies. The proposed computational framework is general and applicable to other liquids, thereby offering great promise in understanding and engineering solutions and liquid electrolytes for a variety of important energy technologies.
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Affiliation(s)
- Tuan Anh Pham
- Quantum Simulations Group, Lawrence Livermore National Laboratory, Livermore, CA 94550, USA
| | - Marco Govoni
- Institute for Molecular Engineering, University of Chicago, Chicago, IL 60637, USA
- Materials Science Division, Argonne National Laboratory, Lemont, IL 60439, USA
| | - Robert Seidel
- Department of Chemistry, University of Southern California, Los Angeles, CA 90089–0482, USA
| | - Stephen E. Bradforth
- Department of Chemistry, University of Southern California, Los Angeles, CA 90089–0482, USA
| | - Eric Schwegler
- Quantum Simulations Group, Lawrence Livermore National Laboratory, Livermore, CA 94550, USA
| | - Giulia Galli
- Institute for Molecular Engineering, University of Chicago, Chicago, IL 60637, USA
- Materials Science Division, Argonne National Laboratory, Lemont, IL 60439, USA
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26
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Izgorodina EI, Seeger ZL, Scarborough DLA, Tan SYS. Quantum Chemical Methods for the Prediction of Energetic, Physical, and Spectroscopic Properties of Ionic Liquids. Chem Rev 2017; 117:6696-6754. [PMID: 28139908 DOI: 10.1021/acs.chemrev.6b00528] [Citation(s) in RCA: 125] [Impact Index Per Article: 17.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The accurate prediction of physicochemical properties of condensed systems is a longstanding goal of theoretical (quantum) chemistry. Ionic liquids comprising entirely of ions provide a unique challenge in this respect due to the diverse chemical nature of available ions and the complex interplay of intermolecular interactions among them, thus resulting in the wide variability of physicochemical properties, such as thermodynamic, transport, and spectroscopic properties. It is well understood that intermolecular forces are directly linked to physicochemical properties of condensed systems, and therefore, an understanding of this relationship would greatly aid in the design and synthesis of functionalized materials with tailored properties for an application at hand. This review aims to give an overview of how electronic structure properties obtained from quantum chemical methods such as interaction/binding energy and its fundamental components, dipole moment, polarizability, and orbital energies, can help shed light on the energetic, physical, and spectroscopic properties of semi-Coulomb systems such as ionic liquids. Particular emphasis is given to the prediction of their thermodynamic, transport, spectroscopic, and solubilizing properties.
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Affiliation(s)
- Ekaterina I Izgorodina
- Monash Computational Chemistry Group, School of Chemistry, Monash University , 17 Rainforest Walk, Clayton, Victoria 3800, Australia
| | - Zoe L Seeger
- Monash Computational Chemistry Group, School of Chemistry, Monash University , 17 Rainforest Walk, Clayton, Victoria 3800, Australia
| | - David L A Scarborough
- Monash Computational Chemistry Group, School of Chemistry, Monash University , 17 Rainforest Walk, Clayton, Victoria 3800, Australia
| | - Samuel Y S Tan
- Monash Computational Chemistry Group, School of Chemistry, Monash University , 17 Rainforest Walk, Clayton, Victoria 3800, Australia
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27
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Yang J, Youssef M, Yildiz B. Predicting point defect equilibria across oxide hetero-interfaces: model system of ZrO2/Cr2O3. Phys Chem Chem Phys 2017; 19:3869-3883. [DOI: 10.1039/c6cp04997d] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
We present a multi-scale model to predict defect redistribution both in interface core and space charge layer across oxide/oxide hetero-interfaces.
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Affiliation(s)
- Jing Yang
- Laboratory for Electrochemical Interfaces
- Massachusetts Institute of Technology
- Cambridge
- USA
- Department of Materials Science and Engineering
| | - Mostafa Youssef
- Laboratory for Electrochemical Interfaces
- Massachusetts Institute of Technology
- Cambridge
- USA
- Department of Materials Science and Engineering
| | - Bilge Yildiz
- Laboratory for Electrochemical Interfaces
- Massachusetts Institute of Technology
- Cambridge
- USA
- Department of Materials Science and Engineering
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28
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Evarestov RA, Gryaznov D, Arrigoni M, Kotomin EA, Chesnokov A, Maier J. Use of site symmetry in supercell models of defective crystals: polarons in CeO2. Phys Chem Chem Phys 2017; 19:8340-8348. [DOI: 10.1039/c6cp08582b] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Polarons and oxygen site symmetry in hybrid DFT calculations.
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Affiliation(s)
- R. A. Evarestov
- Department of Chemistry
- St. Petersburg State University
- St. Petersburg
- Russia
| | - D. Gryaznov
- Department of Theoretical Physics and Computer Modelling
- Institute of Solid State Physics
- University of Latvia
- Riga
- Latvia
| | - M. Arrigoni
- Department of Physical Chemistry of Solids
- Max Planck Institute for Solid State Research
- Stuttgart
- Germany
| | - E. A. Kotomin
- Department of Theoretical Physics and Computer Modelling
- Institute of Solid State Physics
- University of Latvia
- Riga
- Latvia
| | - A. Chesnokov
- Department of Theoretical Physics and Computer Modelling
- Institute of Solid State Physics
- University of Latvia
- Riga
- Latvia
| | - J. Maier
- Department of Physical Chemistry of Solids
- Max Planck Institute for Solid State Research
- Stuttgart
- Germany
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29
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DFT modeling of plasma-assisted atomic layer deposition for Si(110) passivation: formation of boehmite-like chains as γ-Al2O3 precursors. Theor Chem Acc 2016. [DOI: 10.1007/s00214-016-1900-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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30
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Fang DQ, Zhang SL. Theoretical prediction of the band offsets at the ZnO/anatase TiO2 and GaN/ZnO heterojunctions using the self-consistent ab initio DFT/GGA-1/2 method. J Chem Phys 2016; 144:014704. [DOI: 10.1063/1.4939518] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- D. Q. Fang
- MOE Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed Matter, School of Science, Xi’an Jiaotong University, Xi’an 710049, China
| | - S. L. Zhang
- MOE Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed Matter, School of Science, Xi’an Jiaotong University, Xi’an 710049, China
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31
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Ko KC, Lamiel-García O, Lee JY, Illas F. Performance of a modified hybrid functional in the simultaneous description of stoichiometric and reduced TiO2polymorphs. Phys Chem Chem Phys 2016; 18:12357-67. [DOI: 10.1039/c6cp00912c] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A modified hybrid functional is proposed to properly describe the electronic structure and physical properties for stoichiometric and reduced TiO2polymorphs.
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Affiliation(s)
- Kyoung Chul Ko
- Departament de Química Física & Institut de Química Teòrica i Computacional (IQTCUB)
- Universitat de Barcelona
- 08028 Barcelona
- Spain
- Department of Chemistry
| | - Oriol Lamiel-García
- Departament de Química Física & Institut de Química Teòrica i Computacional (IQTCUB)
- Universitat de Barcelona
- 08028 Barcelona
- Spain
| | - Jin Yong Lee
- Department of Chemistry
- Sungkyunkwan University
- Suwon 16419
- Korea
| | - Francesc Illas
- Departament de Química Física & Institut de Química Teòrica i Computacional (IQTCUB)
- Universitat de Barcelona
- 08028 Barcelona
- Spain
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32
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Shimazaki T, Nakajima T. Application of the dielectric-dependent screened exchange potential approach to organic photocell materials. Phys Chem Chem Phys 2016; 18:27554-27563. [DOI: 10.1039/c6cp04863c] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
This paper discusses the fundamental features of the dielectric-dependent screened exchange potential approach for organic molecules and photocell materials.
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33
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Ambrosio F, Miceli G, Pasquarello A. Redox levels in aqueous solution: Effect of van der Waals interactions and hybrid functionals. J Chem Phys 2015; 143:244508. [DOI: 10.1063/1.4938189] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Affiliation(s)
- Francesco Ambrosio
- Chaire de Simulation à l’Echelle Atomique (CSEA), Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Giacomo Miceli
- Chaire de Simulation à l’Echelle Atomique (CSEA), Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Alfredo Pasquarello
- Chaire de Simulation à l’Echelle Atomique (CSEA), Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
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34
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Du MH. Density Functional Calculations of Native Defects in CH3NH3PbI3: Effects of Spin-Orbit Coupling and Self-Interaction Error. J Phys Chem Lett 2015; 6:1461-6. [PMID: 26263152 DOI: 10.1021/acs.jpclett.5b00199] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Native point defects play an important role in carrier transport properties of CH3NH3PbI3. However, the nature of many important defects remains controversial due partly to the conflicting results reported by recent density functional theory (DFT) calculations. In this Letter, we show that self-interaction error and the neglect of spin-orbit coupling (SOC) in many previous DFT calculations resulted in incorrect positions of valence and conduction band edges, although their difference, which is the band gap, is in good agreement with the experimental value. This problem has led to incorrect predictions of defect-level positions. Hybrid density functional calculations, which partially correct the self-interaction error and include the SOC, show that, among native point defects (including vacancies, interstitials, and antisites), only the iodine vacancy and its complexes induce deep electron and hole trapping levels inside of the band gap, acting as nonradiative recombination centers.
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35
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Chen W, Pasquarello A. First-principles determination of defect energy levels through hybrid density functionals and GW. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2015; 27:133202. [PMID: 25744104 DOI: 10.1088/0953-8984/27/13/133202] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
In this topical review, we discuss recent progress in electronic-structure methods for calculating defect energy levels in semiconductors and insulators. We concentrate mainly on two advanced electronic-structure schemes, namely hybrid density functional theory and many-body perturbation theory in the GW approximation. These two schemes go beyond standard density functional theory in the semilocal approximation providing a more realistic description of band gaps. In particular, we address important aspects underlying the GW scheme and highlight the correspondence between the defect levels as obtained in the various schemes. We further assess the quality of the band-edge positions determined with hybrid functionals and GW through the calculation of band-offsets at semiconductor heterojunctions and of ionization potentials at semiconductor surfaces.
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Affiliation(s)
- Wei Chen
- Chaire de Simulation à l'Echelle Atomique (CSEA), Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
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36
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Shimazaki T, Nakajima T. Theoretical study of a screened Hartree–Fock exchange potential using position-dependent atomic dielectric constants. J Chem Phys 2015; 142:074109. [DOI: 10.1063/1.4908061] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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37
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Ping Y, Sundararaman R, Goddard III WA. Solvation effects on the band edge positions of photocatalysts from first principles. Phys Chem Chem Phys 2015; 17:30499-509. [DOI: 10.1039/c5cp05740j] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Continuum solvation theories predict large shifts in band positions of photocatalysts from vacuum to solution, in agreement with experiment.
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Affiliation(s)
- Yuan Ping
- Joint Center for Artificial Photosynthesis
- USA
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38
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Yu J, Yan Q, Chen W, Jain A, Neaton JB, Persson KA. First-principles study of electronic structure and photocatalytic properties of MnNiO3 as an alkaline oxygen-evolution photocatalyst. Chem Commun (Camb) 2015; 51:2867-70. [DOI: 10.1039/c4cc08111k] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We present a first-principles study of MnNiO3, a promising oxygen-evolution photocatalyst.
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Affiliation(s)
- Jie Yu
- Joint Center for Artificial Photosynthesis
- Lawrence Berkeley National Laboratory
- Berkeley
- USA
- Environmental Energy Technologies Division, Lawrence Berkeley National Laboratory
| | - Qimin Yan
- Molecular Foundry
- Lawrence Berkeley National Laboratory
- Berkeley
- USA
- Department of Physics
| | - Wei Chen
- Environmental Energy Technologies Division, Lawrence Berkeley National Laboratory
- Berkeley
- USA
| | - Anubhav Jain
- Environmental Energy Technologies Division, Lawrence Berkeley National Laboratory
- Berkeley
- USA
| | - Jeffrey B. Neaton
- Molecular Foundry
- Lawrence Berkeley National Laboratory
- Berkeley
- USA
- Department of Physics
| | - Kristin A. Persson
- Environmental Energy Technologies Division, Lawrence Berkeley National Laboratory
- Berkeley
- USA
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39
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Shimazaki T, Nakajima T. Dielectric-dependent screened Hartree–Fock exchange potential and Slater-formula with Coulomb-hole interaction for energy band structure calculations. J Chem Phys 2014; 141:114109. [DOI: 10.1063/1.4895623] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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40
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Abstract
The ability to predict energy levels in metal oxides is paramount to developinguseful materials, such as in the development of water photolysis catalysts and efficient photovoltaic cells. The binding energy of electrons in materials encompasses a wealth of information concerning their physicochemistry. The energies control the optical and electrical properties, dictating for which kinds of chemistry and physics a particular material is useful. Scientists have developed theories and models for electron energies in a variety of chemical systems over the past century. However, the prediction of quantitative energy levels in new materials remains a major challenge. This issue is of particular importance in metal oxide research, where novel chemistries have opened the possibility of a wide range of tailored systems with applications in important fields including light-emitting diodes, energy efficient glasses, and solar cells. In this Account, we discuss the application of atomistic modeling techniques, covering the spectrum from classical to quantum descriptions, to explore the alignment of electron energies between materials. We present a number of paradigmatic examples, including a series of oxides (ZnO, In2O3, and Cu2O). Such calculations allow the determination of a "band alignment diagram" between different materials and can facilitate the prediction of the optimal chemical composition of an oxide for use in a given application. Throughout this Account, we consider direct computational solutions in the context of heuristic models, which are used to relate the fundamental theory to experimental observations. We review a number of techniques that have been commonly applied in the study of electron energies in solids. These models have arisen from different answers to the same basic question, coming from solid-state chemistry and physics perspectives. We highlight common factors, as well as providing a critical appraisal of the strengths and weaknesses of each, emphasizing the difficulties in translating concepts from molecular to solid-state systems. Finally, we stress the need for a universal description of the alignment of band energies for materials design from first-principles. By demonstrating the applicability and challenges of using theory to calculate the relevant quantities, as well as impressing the necessity of a clarification and unification of the descriptions, we hope to provide a stimulus for the continued development of this field.
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Affiliation(s)
- Aron Walsh
- Centre for Sustainable Chemical Technologies and Department of Chemistry, University of Bath, Bath BA2 7AY, U.K
| | - Keith T. Butler
- Centre for Sustainable Chemical Technologies and Department of Chemistry, University of Bath, Bath BA2 7AY, U.K
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41
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Zhang Y, Fu Z, Dong S, Yang Z. The mechanisms for the high resistance to sulfur poisoning of the Ni/yttria-stabilized zirconia system treated with Sn vapor. Phys Chem Chem Phys 2014; 16:1033-40. [DOI: 10.1039/c3cp53824a] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
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42
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Xu Y, Hofmann OT, Schlesinger R, Winkler S, Frisch J, Niederhausen J, Vollmer A, Blumstengel S, Henneberger F, Koch N, Rinke P, Scheffler M. Space-charge transfer in hybrid inorganic-organic systems. PHYSICAL REVIEW LETTERS 2013; 111:226802. [PMID: 24329464 DOI: 10.1103/physrevlett.111.226802] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2013] [Indexed: 05/24/2023]
Abstract
We discuss density functional theory calculations of hybrid inorganic-organic systems that explicitly include the global effects of doping (i.e., position of the Fermi level) and the formation of a space-charge layer. For the example of tetrafluoro-tetracyanoquinodimethane on the ZnO(0001[over ¯]) surface we show that the adsorption energy and electron transfer depend strongly on the ZnO doping. The associated work function changes are large, for which the formation of space-charge layers is the main driving force. The prominent doping effects are expected to be quite general for charge-transfer interfaces in hybrid inorganic-organic systems and important for device design.
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Affiliation(s)
- Yong Xu
- Fritz-Haber-Institut der Max-Planck-Gesellschaft, 14195 Berlin, Germany
| | - Oliver T Hofmann
- Fritz-Haber-Institut der Max-Planck-Gesellschaft, 14195 Berlin, Germany
| | | | - Stefanie Winkler
- Helmholtz-Zentrum Berlin für Materialien und Energie GmbH-BESSY II, 12489 Berlin, Germany
| | - Johannes Frisch
- Humboldt-Universität zu Berlin, Institut für Physik, 12489 Berlin, Germany
| | - Jens Niederhausen
- Humboldt-Universität zu Berlin, Institut für Physik, 12489 Berlin, Germany
| | - Antje Vollmer
- Helmholtz-Zentrum Berlin für Materialien und Energie GmbH-BESSY II, 12489 Berlin, Germany
| | - Sylke Blumstengel
- Humboldt-Universität zu Berlin, Institut für Physik, 12489 Berlin, Germany
| | - Fritz Henneberger
- Humboldt-Universität zu Berlin, Institut für Physik, 12489 Berlin, Germany
| | - Norbert Koch
- Humboldt-Universität zu Berlin, Institut für Physik, 12489 Berlin, Germany and Helmholtz-Zentrum Berlin für Materialien und Energie GmbH-BESSY II, 12489 Berlin, Germany
| | - Patrick Rinke
- Fritz-Haber-Institut der Max-Planck-Gesellschaft, 14195 Berlin, Germany
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Oda T, Zhang Y, Weber WJ. Study of intrinsic defects in 3C-SiC using first-principles calculation with a hybrid functional. J Chem Phys 2013; 139:124707. [PMID: 24089795 DOI: 10.1063/1.4821937] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Takuji Oda
- Department of Materials Science and Engineering, University of Tennessee, Knoxville, Tennessee 37996, USA
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44
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45
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Huang GY, Abdul-Jabbar NM, Wirth BD. First-principles study of the structure and band structure of Ga2Se3. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2013; 25:225503. [PMID: 23673396 DOI: 10.1088/0953-8984/25/22/225503] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Our first-principles calculations show that the ordering of stoichiometric cation vacancies in Ga2Se3 has a large influence on the bandgap, up to 0.55 eV. Therein, the zigzag-line vacancy-ordered Ga2Se3 has the maximum bandgap (∼2.56 eV direct bandgap), and the straight-line vacancy-ordered Ga2Se3 has the minimum bandgap (∼1.99 eV indirect bandgap) at 0 K, according to scGW calculations. The bandgap difference (0.55 eV) is almost the same for normal density functional theory (DFT) calculations, hybrid DFT calculations and GW calculations. The calculation results are consistent with the experimental bandgap range of 2.0-2.6 eV at room temperature. Also, hydrostatic pressure (<9 GPa) tends to increase the bandgap, consistent with the experiments in the literature.
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Affiliation(s)
- Gui-Yang Huang
- Department of Nuclear Engineering, University of Tennessee, Knoxville, TN, USA.
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46
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Lu YB, Dai Y, Guo M, Yu L, Huang B. Investigation of magnetic properties induced by group-V element in doped ZnO. Phys Chem Chem Phys 2013; 15:5208-14. [DOI: 10.1039/c3cp44047h] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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47
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Wang Z, Zhao M, Wang X, Xi Y, He X, Liu X, Yan S. Hybrid density functional study of band alignment in ZnO–GaN and ZnO–(Ga1−xZnx)(N1−xOx)–GaN heterostructures. Phys Chem Chem Phys 2012; 14:15693-8. [DOI: 10.1039/c2cp42115a] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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48
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Nagoya A, Asahi R, Kresse G. First-principles study of Cu2ZnSnS4 and the related band offsets for photovoltaic applications. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2011; 23:404203. [PMID: 21931185 DOI: 10.1088/0953-8984/23/40/404203] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
First-principles calculations of the band offsets between Cu(2)ZnSnS(4) (CZTS) and XS (X = Cd, Zn) are performed. While the interface dipole contribution for the band offsets is calculated using the Perdew-Burke-Ernzerhof functional, the Heyd-Scuseria-Ernzerhof hybrid functional is employed to introduce the quasiparticle corrections to the band offsets. The calculated conduction band offset between CZTS and CdS is 0.2 eV, validating CdS for the buffer layer of the CZTS solar cell. The small conduction band offset stems from the band gap narrowing of CdS under the interface strain caused by the lattice misfit with CZTS. A large valence band offset over 0.9 eV between CZTS and ZnS indicates that precipitated ZnS is regarded as an inactive insulator phase in CZTS absorbers.
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Affiliation(s)
- A Nagoya
- Toyota Central R&D Laboratories, Incorporated, Nagakute, Aichi 480-1192, Japan.
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49
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Oba F, Choi M, Togo A, Tanaka I. Point defects in ZnO: an approach from first principles. SCIENCE AND TECHNOLOGY OF ADVANCED MATERIALS 2011; 12:034302. [PMID: 27877390 PMCID: PMC5090462 DOI: 10.1088/1468-6996/12/3/034302] [Citation(s) in RCA: 73] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2011] [Revised: 05/27/2011] [Accepted: 03/16/2011] [Indexed: 05/03/2023]
Abstract
Recent first-principles studies of point defects in ZnO are reviewed with a focus on native defects. Key properties of defects, such as formation energies, donor and acceptor levels, optical transition energies, migration energies and atomic and electronic structure, have been evaluated using various approaches including the local density approximation (LDA) and generalized gradient approximation (GGA) to DFT, LDA+U/GGA+U, hybrid Hartree-Fock density functionals, sX and GW approximation. Results significantly depend on the approximation to exchange correlation, the simulation models for defects and the post-processes to correct shortcomings of the approximation and models. The choice of a proper approach is, therefore, crucial for reliable theoretical predictions. First-principles studies have provided an insight into the energetics and atomic and electronic structures of native point defects and impurities and defect-induced properties of ZnO. Native defects that are relevant to the n-type conductivity and the non-stoichiometry toward the O-deficient side in reduced ZnO have been debated. It is suggested that the O vacancy is responsible for the non-stoichiometry because of its low formation energy under O-poor chemical potential conditions. However, the O vacancy is a very deep donor and cannot be a major source of carrier electrons. The Zn interstitial and anti-site are shallow donors, but these defects are unlikely to form at a high concentration in n-type ZnO under thermal equilibrium. Therefore, the n-type conductivity is attributed to other sources such as residual impurities including H impurities with several atomic configurations, a metastable shallow donor state of the O vacancy, and defect complexes involving the Zn interstitial. Among the native acceptor-type defects, the Zn vacancy is dominant. It is a deep acceptor and cannot produce a high concentration of holes. The O interstitial and anti-site are high in formation energy and/or are electrically inactive and, hence, are unlikely to play essential roles in electrical properties. Overall defect energetics suggests a preference for the native donor-type defects over acceptor-type defects in ZnO. The O vacancy, Zn interstitial and Zn anti-site have very low formation energies when the Fermi level is low. Therefore, these defects are expected to be sources of a strong hole compensation in p-type ZnO. For the n-type doping, the compensation of carrier electrons by the native acceptor-type defects can be mostly suppressed when O-poor chemical potential conditions, i.e. low O partial pressure conditions, are chosen during crystal growth and/or doping.
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Affiliation(s)
- Fumiyasu Oba
- Department of Materials Science and Engineering, Kyoto University, Sakyo, Kyoto 606-8501, Japan
| | - Minseok Choi
- Department of Materials Science and Engineering, Kyoto University, Sakyo, Kyoto 606-8501, Japan
| | - Atsushi Togo
- Department of Materials Science and Engineering, Kyoto University, Sakyo, Kyoto 606-8501, Japan
| | - Isao Tanaka
- Department of Materials Science and Engineering, Kyoto University, Sakyo, Kyoto 606-8501, Japan
- Nanostructures Research Laboratory, Japan Fine Ceramics Center, Atsuta, Nagoya 456-8587, Japan
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50
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Bruska MK, Czekaj I, Delley B, Mantzaras J, Wokaun A. Electronic structure and oxygen vacancies in PdO and ZnO: validation of DFT models. Phys Chem Chem Phys 2011; 13:15947-54. [DOI: 10.1039/c1cp20923j] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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