First Principle Investigation on Electronic Properties of Cationic and Anionic CO-Alloyed Cu2ZnSnS4 Kesterite Material
The primary goal of kesterite alloying is to allow for fine tweaking of the material's characteristics for advanced device engineering. Additionally, it is seen as a viable solution to inherent kesterite absorber difficulties such as the Cu/Zn disorder or Sn multivalency. The most interestin...
| Main Authors: | , , , |
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| Format: | Article |
| Language: | English |
| Published: |
Department of Physics, Kaduna State University, Nigeria
2022-12-01
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| Series: | Physics Access |
| Subjects: | |
| Online Access: | https://physicsaccess.com/articles/published/PA-JPET-SPECIAL_36.pdf |
| Summary: | The primary goal of kesterite alloying is to allow for fine tweaking of the material's
characteristics for advanced device engineering. Additionally, it is seen as a viable solution to
inherent kesterite absorber difficulties such as the Cu/Zn disorder or Sn multivalency. The most
interesting alloying elements for kesterite are Ag replacing Cu, Cd replacing Zn, and Ge
replacing Sn for cationic substitution, as well as Se replacing S for anionic substitution. This
research work investigates the effect of alloying CZTS with Silver (Ag) (Cation) and Selenium
(Se) (Anion) theoretically using Density Functional Theory (DFT). The compounds were found
to exhibit indirect bandgap characteristics, with conduction band minima (CBM) and valence
band maxima (VBM) located between the N and gamma points of the Brillouin zone for pure
kesterite Cu2ZnSnS4 and between the N and A points for alloyed Ag2ZnSnSe4 respectively. The
bandgap of around 1.22 eV and 0.78 eV were recorded for the pure and alloyed kesterite
materials. From the obtained results, a shrink in bandgap was observed due to the presence of
heavy anion (Se) and cation (Ag) alloying at the same time. It was also found that the
contribution of different atomic orbitals to the formation of the valence and conduction bands
is approximately identical for pure and alloyed materials. |
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| ISSN: | 2714-500X 2756-3898 |