Numerical analysis of the effect of MoS2 interface layers on copper-zinc-tin-sulfur thin film solar cells

MoS2 interface layers are often present in high-temperature sulfurized Cu2ZnSnS4 (CZTS) solar cells, but their effects remain poorly characterized. In this study, the effect of MoS2 on CZTS solar cells was analyzed in simulation. Meanwhile, the quantum confinement effects of MoS2, that is, the varied band gap of MoS2 with the thickness of MoS2 have been considered. When the thickness of MoS2 was varied, the performances of CZTS solar cells were improved by the p-type and n-type MoS2 with suitable thickness due to the reduction of band gap, decreasing height of barrier of p-CZTS/MoS2. The barrier was always observed at the MoS2/Mo interface. When the holes recombination velocity of MoS2/Mo interface was changed, the photovoltaic properties of CZTS solar cells were improved by the suitable recombination velocity of MoS2/Mo interface. The simulated results about the effect of MoS2 thickness were consistent with the reported experiment results.