Study of the band alignment at the CZTS/ZrS₂ interface based on first-principles calculation

Abstract To explore whether ZrS 2 monolayer has the potential to become a buffer layer material for Cu 2 ZnSnS 4 (CZTS) solar cells, the band arrangement of CZTS/ZrS 2 heterojunction was predicted using density functional theory(DFT) first principles. In this paper, the hybrid functional HSE06 is used in all processes. The calculated results reveal a Type III band alignment at the CZTS/ZrS 2 heterojunction interface, with the maximum valence band (VBM) of CZTS positioned 1.67 eV higher than the minimum conduction value (CBM) of ZrS 2 . The results indicate that the CZTS/ZrS 2 interface may not be well-suited for utilization in solar cells, pointing towards potential areas for further investigation.