摘要
Based on ab initio electronic structure calculations by self-interaction-corrected local-density-approximation (SIC-LDA) with the Korringa-Kohn-Rostoker coherent potential approximation (KKR-CPA), we propose a materials design for high efficiency photovoltaic solar cells (PVSCs). It is shown that (i) the concentration dependence of the mixing energy of shows upward convexity, thus this system favors phase separation. Due to the type II band alignment between and , efficient electron-hole separation is realized in decomposed phase of this system. (ii) has a direct band gap and no impurity state appears in the gap. Therefore, cost reduction is possible by using Zn and Sn instead of In. (iii) n-type and p-type have negative activation energy for doped impurities and are expected to be low-resistive transparent conducting sulfides, which should be useful for -based PVSCs.