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Abed HH, Al-Khaykanee MK, Abduljalil HM, Abdulsattar MA. Investigation of thermoelectric properties of cadmium selenide Cd nSe n (n= 7, 11, 13) molecular junctions: a DFT study. J Mol Model 2023; 30:12. [PMID: 38102331 DOI: 10.1007/s00894-023-05805-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2023] [Accepted: 12/06/2023] [Indexed: 12/17/2023]
Abstract
CONTEXT The thermoelectric properties of cadmium selenide (CdnSen) molecular junctions (n = 7, 11, 13) were investigated before and after adding hydrogen atoms. The effects of hydrogen passivation on the transmission and thermopower curves were analyzed. CdSe-diamantane (Cd7Se7) and CdSe-tetramantane (Cd11Se11) junctions exhibited the best thermoelectric performance due to their low surface reconstruction energy, which is attributed to the number of dangling and unsaturated bonds. This study guides the design of new molecular junctions with desired thermoelectric properties. METHOD The electrical and thermal properties of cadmium selenide (CdnSen) molecular junctions (n = 7, 11, 13) were investigated using a ballistic quantum transport method based on the non-equilibrium Green's function (NEGF) approach. Thermoelectric properties were calculated for the molecular junctions with different structures before and after hydrogen passivation. Density functional theory (DFT) calculations were performed at the B3LYP level with the 3-21G basis set for the Cd atoms and the 6-31G** basis set for the Se atoms. The SIESTA and GOLLUM codes were used to study the effect of changing the shape and size of each structure on its electrical and thermal characteristics.
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Affiliation(s)
- Hussein Hakim Abed
- Department of Physics, College of Science, University of Babylon, Hilla, Iraq.
| | | | - Hayder M Abduljalil
- Department of Physics, College of Science, University of Babylon, Hilla, Iraq
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Fenoll D, Sodupe M, Solans-Monfort X. Influence of Capping Ligands, Solvent, and Thermal Effects on CdSe Quantum Dot Optical Properties by DFT Calculations. ACS OMEGA 2023; 8:11467-11478. [PMID: 37008094 PMCID: PMC10061629 DOI: 10.1021/acsomega.3c00324] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/16/2023] [Accepted: 03/07/2023] [Indexed: 06/19/2023]
Abstract
Cadmium selenide nanomaterials are very important materials in photonics, catalysis, and biomedical applications due to their optical properties that can be tuned through size, shape, and surface passivation. In this report, static and ab initio molecular dynamics density functional theory (DFT) simulations are used to characterize the effect of ligand adsorption on the electronic properties of the (110) surface of zinc blende and wurtzite CdSe and a (CdSe)33 nanoparticle. Adsorption energies depend on ligand surface coverage and result from a balance between chemical affinity and ligand-surface and ligand-ligand dispersive interactions. In addition, while little structural reorganization occurs upon slab formation, Cd···Cd distances become shorter and the Se-Cd-Se angles become smaller in the bare nanoparticle model. This originates mid-gap states that strongly influence the absorption optical spectra of nonpassivated (CdSe)33. Ligand passivation on both zinc blende and wurtzite surfaces does not induce a surface reorganization, and thus, the band gap remains nonaffected with respect to bare surfaces. In contrast, structural reconstruction is more apparent for the nanoparticle, which significantly increases its highest occupied molecular orbital (HOMO)-lowest unoccupied molecular orbital (LUMO) gap upon passivation. Solvent effects decrease the band gap difference between the passivated and nonpassivated nanoparticles, the maximum of the absorption spectra being blue-shifted around 20 nm by the effect of the ligands. Overall, calculations show that flexible surface cadmium sites are responsible for the appearance of mid-gap states that are partially localized on the most reconstructed regions of the nanoparticle that can be controlled through appropriate ligand adsorption.
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Luise D, Wilbraham L, Labat F, Ciofini I. Modeling UV-Vis spectra of low dimensional materials using electrostatic embedding: The case of CdSe. J Comput Chem 2021; 42:1212-1224. [PMID: 33978978 DOI: 10.1002/jcc.26534] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Revised: 02/23/2021] [Accepted: 03/01/2021] [Indexed: 11/08/2022]
Abstract
We present a generalization of a self-consistent electrostatic embedding approach (SC-Ewald) devised to investigate the photophysical properties of 3D periodic materials, to systems in one- or two-dimensional (2D) reduced periodicity. In this approach, calculations are carried out on a small finite molecular cluster extracted from a periodic model, while the crystalline environment is accounted for by an array of point charges which are fitted to reproduce the exact electrostatic potential (at ground or the excited state) of the infinite periodic system. Periodic density functional theory (DFT) calculations are combined with time dependent DFT calculations to simulate absorption and emission properties of the extended system under investigation. We apply this method to compute the UV-Vis. spectra of bulk and quantum-confined 0D quantum dots and 2D extended nanoplatelets of CdSe, due to their relevance as sensitizers in solar cells technologies. The influence of the size and shape of the finite cluster model chosen in the excited state calculations was also investigated and revealed that, although the long-range electrostatics of the environment are important for the calculation of the UV-Vis, a subtle balance between short- and long-range effects exists. These encouraging results demonstrate that this self-consistent electrostatic embedding approach, when applied in different dimensions, can successfully model the photophysical properties of diverse material classes, making it an attractive low-cost alternative to far more computationally demanding electronic structure methods for excited state calculations.
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Affiliation(s)
- Davide Luise
- Chimie ParisTech, PSL University, CNRS, Institute of Chemistry for Life and Health Sciences, Chemical Theory and Modelling Group, Paris, France
| | | | - Frédéric Labat
- Chimie ParisTech, PSL University, CNRS, Institute of Chemistry for Life and Health Sciences, Chemical Theory and Modelling Group, Paris, France
| | - Ilaria Ciofini
- Chimie ParisTech, PSL University, CNRS, Institute of Chemistry for Life and Health Sciences, Chemical Theory and Modelling Group, Paris, France
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Du N, Cui Y, Zhang L, Yang M. Effect of Mn doping on the electron injection in CdSe/TiO 2 quantum dot sensitized solar cells. Phys Chem Chem Phys 2021; 23:647-656. [PMID: 33332495 DOI: 10.1039/d0cp03866k] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Promotion in power conversion efficiency is an appealing task for quantum dot-sensitized solar cells that have emerged as promising materials for the utilization of clean and sustainable energy. Doping of Mn atoms into quantum dots (QD) has been proven to be one of the effective approaches, although the origin of such a promotion remains controversial. While several procedures are involved in the power conversion process, electron injection from the QD to the semiconductor oxide substrate is focused on in this work using first-principles calculations. Based on the Marcus theory, the electron injection rates are evaluated for the quantum dot-sensitized solar cell models in which the pure and Mn-doped core-shell CdSe clusters are deposited on a semiconductor titanium dioxide substrate. Enhanced rates are obtained for the Mn-doped structure, which is in qualitative agreement with the experiments. A large number of dominant injection channels and strong QD-substrate coupling are responsible for the Mn-induced rate enhancement, which could be achieved by manipulating the band structure mapping between the QD and the semiconductor oxide. By addressing the role of an Mn dopant in the electron injection process, strategies for the promotion of electron injection rates are proposed for the design of quantum dot-sensitized solar cells.
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Affiliation(s)
- Ning Du
- Institute of Atomic and Molecular Physics, Sichuan University, Chengdu 610065, China.
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Li W, Zhao X, Liu C, Coudert FX. Ab Initio Molecular Dynamics of CdSe Quantum-Dot-Doped Glasses. J Am Chem Soc 2020; 142:3905-3912. [PMID: 32011133 DOI: 10.1021/jacs.9b12073] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
We have probed the local atomic structure of the interface between a CdSe quantum dot (QD) and a sodium silicate glass matrix. Using ab initio molecular dynamics simulations, we determined the structural properties and bond lengths, in excellent agreement with previous experimental observations. On the basis of an analysis of radial distribution functions, coordination environment, and ring structures, we demonstrate that an important structural reconstruction occurs at the interface between the CdSe QD and the glass matrix. The incorporation of the CdSe QD disrupts the Na-O bonds, while stronger SiO4 tetrahedra are reformed. The existence of the glass matrix breaks the stable 4-membered (4MR) and 6-membered (6MR) Cd-Se rings, and we observe a disassociated Cd atom migrated in the glass matrix. Besides, the formation of Se-Na and Cd-O linkages is observed at the CdSe QD/glass interface. These results significantly extend our understanding of the interfacial structure of CdSe QD-doped glasses and provide physical and chemical insight into the possible defect structure origin of CdSe QD, of interest to the fabrication of the highly luminescent CdSe QD-doped glasses.
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Affiliation(s)
- Wenke Li
- State Key Laboratory of Silicate Materials for Architectures , Wuhan University of Technology , Hubei 430070 , China.,Chimie ParisTech, PSL University, CNRS, Institut de Recherche de Chimie Paris , 75005 Paris , France
| | - Xiujian Zhao
- State Key Laboratory of Silicate Materials for Architectures , Wuhan University of Technology , Hubei 430070 , China
| | - Chao Liu
- State Key Laboratory of Silicate Materials for Architectures , Wuhan University of Technology , Hubei 430070 , China
| | - François-Xavier Coudert
- Chimie ParisTech, PSL University, CNRS, Institut de Recherche de Chimie Paris , 75005 Paris , France
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Jäger M, Schneider J, Schäfer R. Size- and Charge-Dependent Optoelectronic Properties of CdSe Clusters: Evolution of the Optical Gap from Molecular to Bulk Behavior. J Phys Chem A 2020; 124:185-196. [DOI: 10.1021/acs.jpca.9b10401] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Marc Jäger
- Eduard-Zintl-Institut für Anorganische und Physikalische Chemie, Alarich-Weiss-Straße 8, 64287 Darmstadt, Germany
| | - Jurek Schneider
- Eduard-Zintl-Institut für Anorganische und Physikalische Chemie, Alarich-Weiss-Straße 8, 64287 Darmstadt, Germany
| | - Rolf Schäfer
- Eduard-Zintl-Institut für Anorganische und Physikalische Chemie, Alarich-Weiss-Straße 8, 64287 Darmstadt, Germany
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Yu S, Huang D, Withanage K. Computational insights into structural and optical properties of P-containing and N-containing ligands capped CdSe clusters. MOLECULAR SIMULATION 2019. [DOI: 10.1080/08927022.2019.1642473] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Affiliation(s)
- Shengping Yu
- College of Chemistry and Environment Protection Engineering, Southwest Minzu University, Chengdu, People’s Republic of China
- Institute of Atomic and Molecular Physics, Sichuan University, Chengdu, People’s Republic of China
| | - Delin Huang
- College of Chemistry and Environment Protection Engineering, Southwest Minzu University, Chengdu, People’s Republic of China
| | - Kushantha Withanage
- Physics Department and Science of Advanced Materials Ph. D Program, Central Michigan University, Mount Pleasant, MI, USA
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Singh I, El-Emam AA, Pathak SK, Srivastava R, Shukla VK, Prasad O, Sinha L. Experimental and theoretical DFT (B3LYP, X3LYP, CAM-B3LYP and M06-2X) study on electronic structure, spectral features, hydrogen bonding and solvent effects of 4-methylthiadiazole-5-carboxylic acid. MOLECULAR SIMULATION 2019. [DOI: 10.1080/08927022.2019.1629434] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Affiliation(s)
- Isha Singh
- Department of Physics, University of Lucknow, Lucknow, India
| | - Ali A. El-Emam
- Department of Medicinal Chemistry, Faculty of Pharmacy, University of Mansoura, Mansoura, Egypt
| | | | | | - Vikas K. Shukla
- Department of Physics, University of Lucknow, Lucknow, India
| | - Onkar Prasad
- Department of Physics, University of Lucknow, Lucknow, India
| | - Leena Sinha
- Department of Physics, University of Lucknow, Lucknow, India
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Nevers DR, Williamson CB, Hanrath T, Robinson RD. Surface chemistry of cadmium sulfide magic-sized clusters: a window into ligand-nanoparticle interactions. Chem Commun (Camb) 2018; 53:2866-2869. [PMID: 28218315 DOI: 10.1039/c6cc09549f] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Optoelectronic properties of nanoparticles are intimately coupled to the complex physiochemical interplay between the inorganic core and the organic ligand shell. Magic-sized clusters, which are predominately surface atoms, provide a promising avenue to clarify these critical surface interactions. Whereas these interactions impact the surface of both nanoparticles and magic-sized clusters, we show here that only clusters manifest a shift in the excitonic peak by up to 0.4 eV upon solvent or ligand treatment. These results highlight the utility of the clusters as a probe of ligand-surface interactions.
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Affiliation(s)
- Douglas R Nevers
- Robert F. Smith School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, New York 14853, USA.
| | - Curtis B Williamson
- Robert F. Smith School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, New York 14853, USA.
| | - Tobias Hanrath
- Robert F. Smith School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, New York 14853, USA.
| | - Richard D Robinson
- Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853, USA.
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Srivastava R, Al-Omary FA, El-Emam AA, Pathak SK, Karabacak M, Narayan V, Chand S, Prasad O, Sinha L. A combined experimental and theoretical DFT (B3LYP, CAM-B3LYP and M06-2X) study on electronic structure, hydrogen bonding, solvent effects and spectral features of methyl 1H-indol-5-carboxylate. J Mol Struct 2017. [DOI: 10.1016/j.molstruc.2017.02.084] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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