Density Functional Theory and Experimental Determination of Band Gaps and Lattice Parameters in Kesterite Cu2ZnSn(SxSe1–x)4



Tong, Chuan-Jia, Edwards, Holly J, Hobson, Theodore DC, Durose, Ken, Dhanak, Vinod R, Major, Jonathan D and McKenna, Keith P
(2020) Density Functional Theory and Experimental Determination of Band Gaps and Lattice Parameters in Kesterite Cu2ZnSn(SxSe1–x)4. The Journal of Physical Chemistry Letters, 11 (24). pp. 10463-10468.

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Abstract

The structures and band gaps of copper-zinc-tin selenosulfides (CZTSSe) are investigated for a range of anion compositions through experimental analysis and complementary first-principles simulations. The band gap was found to be extremely sensitive to the Sn-anion bond length, with an almost linear correlation with the average Sn-anion bond length in the mixed anion phase Cu<sub>2</sub>ZnSn(S<sub><i>x</i></sub>Se<sub>1-<i>x</i></sub>)<sub>4</sub>. Therefore, an accurate prediction of band gaps using first-principles methods requires the accurate reproduction of the experimental bond lengths. This is challenging for many widely used approaches that are suitable for large supercells. The HSE06 functional was found to predict the structure and band gap in good agreement with the experiment but is computationally expensive for large supercells. It was shown that a geometry optimization with the MS2 meta-GGA functional followed by a single point calculation of electronic properties using HSE06 is a reasonable compromise for modeling larger supercells that are often unavoidable in the study of point and extended defects.

Item Type: Article
Uncontrolled Keywords: 34 Chemical Sciences, 51 Physical Sciences, 5104 Condensed Matter Physics
Depositing User: Symplectic Admin
Date Deposited: 11 Dec 2020 11:12
Last Modified: 20 Jun 2024 23:49
DOI: 10.1021/acs.jpclett.0c03205
Related URLs:
URI: https://livrepository.liverpool.ac.uk/id/eprint/3109986