1
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Chang Y, Yates JR, Patrick CE. First-Principles Band Alignments at the Si:Anatase TiO 2 Interface. ACS OMEGA 2023; 8:20138-20147. [PMID: 37305305 PMCID: PMC10249118 DOI: 10.1021/acsomega.3c02865] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/26/2023] [Accepted: 05/08/2023] [Indexed: 06/13/2023]
Abstract
TiO2 has been identified as a promising electron transport layer in Si solar cells. Experiments have revealed that the Si:TiO2 interface undergoes structural changes depending on how it was fabricated. However, less is understood about the sensitivity of electronic properties, such as band alignments, to these changes. Here, we present first-principles calculations of band alignments between Si and anatase TiO2, investigating different surface orientations and terminations. By calculating vacuum-level alignments, we observe a large band offset reduction of 2.5 eV for the O-terminated Si slab compared to other terminations. Furthermore, a 0.5 eV increase is found for the anatase (101) surface compared to (001). We compare the band offsets obtained through vacuum alignment with four different heterostructure models. Even though the heterostructure models contain an excess of oxygen, their offsets agree well with vacuum-level alignments using stoichiometric or H-terminated slabs, and the reduction in band offsets seen for the O-terminated Si slab is not observed. Additionally, we have investigated different exchange-correlation treatments including PBE + U, postprocessing GW corrections, and the meta-GGA rSCAN functional. We find that rSCAN provides more accurate band offsets than PBE, but further corrections are still required to achieve <0.5 eV accuracy. Overall, our study quantifies the importance of surface termination and orientation for this interface.
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2
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Gemeri D, Tremblay J, Pastore M, Bahmann H. Electronic structure, optical properties, and electron dynamics in organic dye-sensitized TiO2 interfaces by local hybrid density functionals. Chem Phys 2022. [DOI: 10.1016/j.chemphys.2022.111521] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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3
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Segalina A, Lebègue S, Rocca D, Piccinin S, Pastore M. Structure and Energetics of Dye-Sensitized NiO Interfaces in Water from Ab Initio MD and Large-Scale GW Calculations. J Chem Theory Comput 2021; 17:5225-5238. [PMID: 34324810 DOI: 10.1021/acs.jctc.1c00354] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The energy-level alignment across solvated molecule/semiconductor interfaces is a crucial property for the correct functioning of dye-sensitized photoelectrodes, where, following the absorption of solar light, a cascade of interfacial hole/electron transfer processes has to efficiently take place. In light of the difficulty of performing X-ray photoelectron spectroscopy measurements at the molecule/solvent/metal-oxide interface, being able to accurately predict the level alignment by first-principles calculations on realistic structural models would represent an important step toward the optimization of the device. In this respect, dye/NiO surfaces, employed in p-type dye-sensitized solar cells, are undoubtedly challenging for ab initio methods and, also for this reason, much less investigated than the n-type dye/TiO2 counterpart. Here, we consider the C343-sensitized NiO surface in water and combine ab initio molecular dynamics (AIMD) simulations with GW (G0W0) calculations, performed along the MD trajectory to reliably describe the structure and energetics of the interface when explicit solvation and finite temperature effects are accounted for. We show that the differential perturbative correction on the NiO and molecule states obtained at the GW level is mandatory to recover the correct (physical) interfacial energetics, allowing hole transfer from the semiconductor valence band to the highest occupied molecular orbital (HOMO) of the dye. Moreover, the calculated average driving force quantitatively agrees with the experimental estimate.
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Affiliation(s)
- Alekos Segalina
- Université de Lorraine & CNRS, LPCT, UMR 7019, F-54000 Nancy, France
| | - Sébastien Lebègue
- Université de Lorraine & CNRS, LPCT, UMR 7019, F-54000 Nancy, France
| | - Dario Rocca
- Université de Lorraine & CNRS, LPCT, UMR 7019, F-54000 Nancy, France
| | - Simone Piccinin
- Consiglio Nazionale delle Ricerche, Istituto Officina dei Materiali, 34136 Trieste, Italy
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4
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Koval P, Ljungberg MP, Müller M, Sánchez-Portal D. Toward Efficient GW Calculations Using Numerical Atomic Orbitals: Benchmarking and Application to Molecular Dynamics Simulations. J Chem Theory Comput 2019; 15:4564-4580. [PMID: 31318555 DOI: 10.1021/acs.jctc.9b00436] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The use of atomic orbitals in Hedin's GW approximation provides, in principle, an inexpensive alternative to plane-wave basis sets, especially when modeling large molecules. However, benchmarking of the algorithms and basis sets is essential for a careful balance between cost and accuracy. In this paper, we present an implementation of the GW approximation using numerical atomic orbitals and a pseudopotential treatment of core electrons. The combination of a contour deformation technique with a one-shot extraction of quasiparticle energies provides an efficient scheme for many applications. The performance of the implementation with respect to the basis set convergence and the effect of the use of pseudopotentials has been tested for the 117 closed-shell molecules from the G2/97 test set and 24 larger acceptor molecules from another recently proposed test set. Moreover, to demonstrate the potential of our method, we compute the thermally averaged GW density of states of a large photochromic compound by sampling ab initio molecular dynamics trajectories at different temperatures. The computed thermal line widths indicate approximately twice as large electron-phonon couplings with GW than with standard DFT-GGA calculations. This is further confirmed using frozen-phonon calculations.
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Affiliation(s)
- Peter Koval
- Donostia International Physics Center , Paseo Manuel de Lardizabal 4 , 20018 Donostia-San Sebastián , Spain
| | - Mathias Per Ljungberg
- Donostia International Physics Center , Paseo Manuel de Lardizabal 4 , 20018 Donostia-San Sebastián , Spain
| | - Moritz Müller
- Donostia International Physics Center , Paseo Manuel de Lardizabal 4 , 20018 Donostia-San Sebastián , Spain
| | - Daniel Sánchez-Portal
- Donostia International Physics Center , Paseo Manuel de Lardizabal 4 , 20018 Donostia-San Sebastián , Spain.,Centro de Física de Materiales , Centro Mixto CSIC-UPV/EHU , Paseo Manuel de Lardizabal 5 , 20018 Donostia-San Sebastián , Spain
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5
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Golze D, Dvorak M, Rinke P. The GW Compendium: A Practical Guide to Theoretical Photoemission Spectroscopy. Front Chem 2019; 7:377. [PMID: 31355177 PMCID: PMC6633269 DOI: 10.3389/fchem.2019.00377] [Citation(s) in RCA: 153] [Impact Index Per Article: 30.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2018] [Accepted: 05/08/2019] [Indexed: 12/22/2022] Open
Abstract
The GW approximation in electronic structure theory has become a widespread tool for predicting electronic excitations in chemical compounds and materials. In the realm of theoretical spectroscopy, the GW method provides access to charged excitations as measured in direct or inverse photoemission spectroscopy. The number of GW calculations in the past two decades has exploded with increased computing power and modern codes. The success of GW can be attributed to many factors: favorable scaling with respect to system size, a formal interpretation for charged excitation energies, the importance of dynamical screening in real systems, and its practical combination with other theories. In this review, we provide an overview of these formal and practical considerations. We expand, in detail, on the choices presented to the scientist performing GW calculations for the first time. We also give an introduction to the many-body theory behind GW, a review of modern applications like molecules and surfaces, and a perspective on methods which go beyond conventional GW calculations. This review addresses chemists, physicists and material scientists with an interest in theoretical spectroscopy. It is intended for newcomers to GW calculations but can also serve as an alternative perspective for experts and an up-to-date source of computational techniques.
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Affiliation(s)
- Dorothea Golze
- Department of Applied Physics, Aalto University, School of Science, Espoo, Finland
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6
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Marom N. Accurate description of the electronic structure of organic semiconductors by GW methods. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2017; 29:103003. [PMID: 28145283 DOI: 10.1088/1361-648x/29/10/103003] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Electronic properties associated with charged excitations, such as the ionization potential (IP), the electron affinity (EA), and the energy level alignment at interfaces, are critical parameters for the performance of organic electronic devices. To computationally design organic semiconductors and functional interfaces with tailored properties for target applications it is necessary to accurately predict these properties from first principles. Many-body perturbation theory is often used for this purpose within the GW approximation, where G is the one particle Green's function and W is the dynamically screened Coulomb interaction. Here, the formalism of GW methods at different levels of self-consistency is briefly introduced and some recent applications to organic semiconductors and interfaces are reviewed.
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Affiliation(s)
- Noa Marom
- Department of Materials Science and Engineering, Department of Chemistry, and Department of Physics, Carnegie Mellon University, Pittsburgh, PA 15213, United States of America
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7
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Global and local aspects of the surface potential landscape for energy level alignment at organic-ZnO interfaces. Chem Phys 2017. [DOI: 10.1016/j.chemphys.2016.11.017] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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8
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Leng X, Jin F, Wei M, Ma Y. GW method and Bethe-Salpeter equation for calculating electronic excitations. WILEY INTERDISCIPLINARY REVIEWS-COMPUTATIONAL MOLECULAR SCIENCE 2016. [DOI: 10.1002/wcms.1265] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Xia Leng
- School of Chemistry and Chemical Engineering; Shandong University; Jinan China
| | - Fan Jin
- School of Chemistry and Chemical Engineering; Shandong University; Jinan China
| | - Min Wei
- School of Chemistry and Chemical Engineering; Shandong University; Jinan China
| | - Yuchen Ma
- School of Chemistry and Chemical Engineering; Shandong University; Jinan China
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9
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Migani A, Mowbray DJ, Zhao J, Petek H. Quasiparticle Interfacial Level Alignment of Highly Hybridized Frontier Levels: H2O on TiO2(110). J Chem Theory Comput 2014; 11:239-51. [DOI: 10.1021/ct500779s] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Affiliation(s)
- Annapaola Migani
- ICN2 - Institut
Català de Nanociència i Nanotecnologia, ICN2 Building,
Campus UAB, E-08193 Bellaterra, Barcelona, Barcelona, Spain
- CSIC - Consejo
Superior de Investigaciones Científicas, ICN2 Building, Campus
UAB, E-08193 Bellaterra,
Barcelona, Barcelona, Spain
| | - Duncan J. Mowbray
- Nano-Bio
Spectroscopy Group and ETSF Scientific Development Center, Departamento
de Física de Materiales, Universidad del País Vasco UPV/EHU and DIPC, E-20018 San Sebastián, Gipuzkoa, Spain
| | - Jin Zhao
- Department
of Physics and ICQD/HFNL, University of Science and Technology of China, Hefei, Anhui 230026, China
- Synergetic Innovation Center of Quantum Information & Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Hrvoje Petek
- Department
of Physics and Astronomy, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
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10
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Migani A, Mowbray DJ. Coverage dependence of the level alignment for methanol on TiO2(110). COMPUT THEOR CHEM 2014. [DOI: 10.1016/j.comptc.2014.03.007] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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11
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Migani A, Mowbray DJ, Zhao J, Petek H, Rubio A. Quasiparticle Level Alignment for Photocatalytic Interfaces. J Chem Theory Comput 2014; 10:2103-13. [DOI: 10.1021/ct500087v] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Affiliation(s)
- Annapaoala Migani
- ICN2—Institut Català de Nanociència i Nanotecnologia and CSIC—Consejo Superior de Investigaciones Cientificas, ICN2 Building, Campus UAB, E-08193 Bellaterra (Barcelona), Spain
- Nano-Bio
Spectroscopy Group and ETSF Scientific Development
Center, Departamento de Física de Materiales, Centro de Física
de Materiales CSIC-UPV/EHU-MPC and DIPC, Universidad del País Vasco UPV/EHU, E-20018 San Sebastián, Spain
| | - Duncan J. Mowbray
- Nano-Bio
Spectroscopy Group and ETSF Scientific Development
Center, Departamento de Física de Materiales, Centro de Física
de Materiales CSIC-UPV/EHU-MPC and DIPC, Universidad del País Vasco UPV/EHU, E-20018 San Sebastián, Spain
| | - Jin Zhao
- Department
of Physics and ICQD/HFNL, University of Science and Technology of China, Hefei, Anhui 230026, China
- Synergetic Innovation Center of Quantum Information & Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Hrvoje Petek
- Department
of Physics and Astronomy, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
| | - Angel Rubio
- Nano-Bio
Spectroscopy Group and ETSF Scientific Development
Center, Departamento de Física de Materiales, Centro de Física
de Materiales CSIC-UPV/EHU-MPC and DIPC, Universidad del País Vasco UPV/EHU, E-20018 San Sebastián, Spain
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12
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Maggio E, Troisi A. An expression for the bridge-mediated electron transfer rate in dye-sensitized solar cells. PHILOSOPHICAL TRANSACTIONS. SERIES A, MATHEMATICAL, PHYSICAL, AND ENGINEERING SCIENCES 2014; 372:20130011. [PMID: 24615149 DOI: 10.1098/rsta.2013.0011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
We have derived an expression for the rate of electron transfer between a semiconductor and a redox centre connected to the semiconductor via a molecular bridge. This model is particularly useful to study the charge recombination (CR) process in dye-sensitized solar cells, where the dye is often connected to the semiconductor by a conjugated bridge. This formalism, designed to be coupled with density functional theory electronic structure calculations, can be used to explore the effect of changing the bridge on the rate of interfacial electron transfer. As an example, we have evaluated the CR rate for a series of systems that differ in the bridge length.
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Affiliation(s)
- Emanuele Maggio
- Department of Chemistry, and Centre for Scientific Computing, University of Warwick, Coventry CV4 7AL, UK
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13
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Kley CS, Dette C, Rinke G, Patrick CE, Cechal J, Jung SJ, Baur M, Dürr M, Rauschenbach S, Giustino F, Stepanow S, Kern K. Atomic-scale observation of multiconformational binding and energy level alignment of ruthenium-based photosensitizers on TiO2 anatase. NANO LETTERS 2014; 14:563-9. [PMID: 24471471 DOI: 10.1021/nl403717d] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Dye-sensitized solar cells constitute a promising approach to sustainable and low-cost solar energy conversion. Their overall efficiency crucially depends on the effective coupling of the photosensitizers to the photoelectrode and the details of the dye's energy levels at the interface. Despite great efforts, the specific binding of prototypical ruthenium-based dyes to TiO2, their potential supramolecular interaction, and the interrelation between adsorption geometry and electron injection efficiency lack experimental evidence. Here we demonstrate multiconformational adsorption and energy level alignment of single N3 dyes on TiO2 anatase (101) revealed by scanning tunnelling microscopy and spectroscopy. The distinctly bound molecules show significant variations of their excited state levels associated with different driving forces for photoelectron injection. These findings emphasize the critical role of the interfacial coupling and suggest that further designs of dye-sensitized solar cells should target a higher selectivity in the dye-substrate binding conformations in order to ensure efficient electron injection from all photosensitizers.
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Affiliation(s)
- Christopher S Kley
- Max Planck Institute for Solid State Research, Heisenbergstrasse 1, 70569 Stuttgart, Germany
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14
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Ørnsø KB, Pedersen CS, Garcia-Lastra JM, Thygesen KS. Optimizing porphyrins for dye sensitized solar cells using large-scale ab initio calculations. Phys Chem Chem Phys 2014; 16:16246-54. [DOI: 10.1039/c4cp01289e] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We present a systematic study of the level alignment of 5145 porphyrin based dyes for dye sensitized solar cells.
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Affiliation(s)
- Kristian B. Ørnsø
- Center for Atomic-scale Materials Design
- Department of Physics
- Technical University of Denmark
- 2800 Kgs. Lyngby, Denmark
| | - Christian S. Pedersen
- Center for Atomic-scale Materials Design
- Department of Physics
- Technical University of Denmark
- 2800 Kgs. Lyngby, Denmark
| | - Juan M. Garcia-Lastra
- Center for Atomic-scale Materials Design
- Department of Physics
- Technical University of Denmark
- 2800 Kgs. Lyngby, Denmark
- Department of Energy Conversion
| | - Kristian S. Thygesen
- Center for Atomic-scale Materials Design
- Department of Physics
- Technical University of Denmark
- 2800 Kgs. Lyngby, Denmark
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15
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Pastore M, Selloni A, Fantacci S, De Angelis F. Electronic and Optical Properties of Dye-Sensitized TiO2 Interfaces. Top Curr Chem (Cham) 2014; 347:1-45. [DOI: 10.1007/128_2013_507] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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16
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Migani A, Mowbray DJ, Iacomino A, Zhao J, Petek H, Rubio A. Level Alignment of a Prototypical Photocatalytic System: Methanol on TiO2(110). J Am Chem Soc 2013; 135:11429-32. [DOI: 10.1021/ja4036994] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Annapaola Migani
- Nano-Bio Spectroscopy Group
and ETSF Scientific Development Center, Departamento de Física
de Materiales, Centro de Física de Materiales CSIC-UPV/EHU-MPC
and DIPC, Universidad del País Vasco UPV/EHU, E-20018 San Sebastián, Spain
- Consejo Superior de Investigaciones Cientificas (CSIC), ICN2 Building,
E-08193 Bellaterra (Barcelona), Spain
| | - Duncan J. Mowbray
- Nano-Bio Spectroscopy Group
and ETSF Scientific Development Center, Departamento de Física
de Materiales, Centro de Física de Materiales CSIC-UPV/EHU-MPC
and DIPC, Universidad del País Vasco UPV/EHU, E-20018 San Sebastián, Spain
| | - Amilcare Iacomino
- Nano-Bio Spectroscopy Group
and ETSF Scientific Development Center, Departamento de Física
de Materiales, Centro de Física de Materiales CSIC-UPV/EHU-MPC
and DIPC, Universidad del País Vasco UPV/EHU, E-20018 San Sebastián, Spain
| | - Jin Zhao
- Physics Department, Hefei National
Laboratory for Physical Sciences at Microscale, University of Science and Technology of China, Hefei, Anhui 230026,
China
| | - Hrvoje Petek
- Department of Physics
and Astronomy, University of Pittsburgh, Pittsburgh, Pennsylvania
15260, United States
| | - Angel Rubio
- Nano-Bio Spectroscopy Group
and ETSF Scientific Development Center, Departamento de Física
de Materiales, Centro de Física de Materiales CSIC-UPV/EHU-MPC
and DIPC, Universidad del País Vasco UPV/EHU, E-20018 San Sebastián, Spain
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17
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Umari P, Giacomazzi L, De Angelis F, Pastore M, Baroni S. Energy-level alignment in organic dye-sensitized TiO2 from GW calculations. J Chem Phys 2013; 139:014709. [DOI: 10.1063/1.4809994] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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18
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Yu M, Doak P, Tamblyn I, Neaton JB. Theory of Covalent Adsorbate Frontier Orbital Energies on Functionalized Light-Absorbing Semiconductor Surfaces. J Phys Chem Lett 2013; 4:1701-1706. [PMID: 26282981 DOI: 10.1021/jz400601t] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Functional hybrid interfaces between organic molecules and semiconductors are central to many emerging information and solar energy conversion technologies. Here we demonstrate a general, empirical parameter-free approach for computing and understanding frontier orbital energies - or redox levels - of a broad class of covalently bonded organic-semiconductor surfaces. We develop this framework in the context of specific density functional theory (DFT) and many-body perturbation theory calculations, within the GW approximation, of an exemplar interface, thiophene-functionalized silicon (111). Through detailed calculations taking into account structural and binding energetics of mixed-monolayers consisting of both covalently attached thiophene and hydrogen, chlorine, methyl, and other passivating groups, we quantify the impact of coverage, nonlocal polarization, and interface dipole effects on the alignment of the thiophene frontier orbital energies with the silicon band edges. For thiophene adsorbate frontier orbital energies, we observe significant corrections to standard DFT (∼1 eV), including large nonlocal electrostatic polarization effects (∼1.6 eV). Importantly, both results can be rationalized from knowledge of the electronic structure of the isolated thiophene molecule and silicon substrate systems. Silicon band edge energies are predicted to vary by more than 2.5 eV, while molecular orbital energies stay similar, with the different functional groups studied, suggesting the prospect of tuning energy alignment over a wide range for photoelectrochemistry and other applications.
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Affiliation(s)
| | - Peter Doak
- ∥Department of Chemistry, University of California, Berkeley, California, United States
| | - Isaac Tamblyn
- ⊥Department of Physics, University of Ontario Institute of Technology, Oshawa, Canada
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