Precisely tuning Ge substitution for efficient solution-processed Cu<sub>2</sub>ZnSn(S, Se)<sub>4</sub> solar cells

Precisely tuning Ge substitution for efficient solution-processed Cu₂ZnSn(S, Se)₄ solar cells

Wang Xinshou, Kou Dongxing^†, Zhou Wenhui, Zhou Zhengji, Tian Qingwen, Meng Yuena, Wu Sixin^‡

(color online) (a) EQE curves and (b) the estimated bandgap of CZTGSSe solar cells with different Ge/(Sn+Ge) ratios.