Crystal structure and electronic structure of quaternary semiconductors Cu$_2$ZnTiSe$_4$ and Cu$_2$ZnTiS$_4$ for solar cell absorber

Xiaofeng Wang; Junjie Li; Zhenjie Zhao; Sumei Huang; Wenhui Xie

doi:10.1063/1.4736554

paper

Crystal structure and electronic structure of quaternary semiconductors Cu $_{2}$ ZnTiSe $_{4}$ and Cu $_{2}$ ZnTiS $_{4}$ for solar cell absorber

arXiv:1203.0644 · doi:10.1063/1.4736554

Abstract

We design two new I2-II-IV-VI4 quaternary semiconductors Cu $_{2}$ ZnTiSe $_{4}$ and Cu $_{2}$ ZnTiS $_{4}$ , and systematically study the crystal and electronic structure by employing first-principles electronic structure calculations. Among the considered crystal structures, it is confirmed that the band gaps of Cu $_{2}$ ZnTiSe $_{4}$ and Cu $_{2}$ ZnTiS $_{4}$ originate from the full occupied Cu 3 $d$ valence band and unoccupied Ti 3 $d$ conducting band, and kesterite structure should be the ground state. Furthermore, our calculations indicate that Cu $_{2}$ ZnTiSe $_{4}$ and Cu $_{2}$ ZnTiS $_{4}$ have comparable band gaps with Cu $_{2}$ ZnTSe $_{4}$ and Cu $_{2}$ ZnTS $_{4}$ , but almost twice larger absorption coefficient $α (ω)$ . Thus, the materials are expected to be candidate materials for solar cell absorber.

4 pages, 4 figures

Crystal structure and electronic structure of quaternary semiconductors Cu2​ZnTiSe4​ and Cu2​ZnTiS4​ for solar cell absorber

Abstract

Crystal structure and electronic structure of quaternary semiconductors Cu $_{2}$ ZnTiSe $_{4}$ and Cu $_{2}$ ZnTiS $_{4}$ for solar cell absorber