“…Besides, Surface functionalization by incorporating some co-catalysts could facilitate the charge separation. Due to the energy level and electronic structure can match up with Cu 2 O, ZnO is often used as co-catalysts [ 45 , 46 , 47 ]. Inspired by these concepts, we put forward an idea where the combination of ZnO co-catalyst and Cu 2 O/g-C 3 N 4 catalyst could be a feasible strategy to prepare high active heterojunction photocatalyst.…”