Boosting efficiency and stability of a Cu2ZnSnS4 photocathode by alloying Ge and increasing sulfur pressure simultaneously

By alloying Ge and increasing sulfur pressure simultaneously, a 27-fold improvement on half-cell solar to hydrogen efficiency (HC-STH) is achieved in a Ge alloyed Cu2ZnSnS4 (Ge/(Ge+Sn) = 0.25) photocathode for solar water splitting.246