Photocatalytic Performance of a Ag/ZnO/CCG Multidimensional Heterostructure Prepared by a Solution-Based Method

The photocatalytic performance of a multidimensional heterojunction composed of decorated Ag nanoparticles on ZnO nanorods vertically grown on a chemically converted graphene (CCG) was investigated. The combined heterojunction helps to improve photocatalytic activity by increasing light absorption, preventing photoinduced electron–hole recombination, and providing a carrier pathway for the giant π-conjugated system of CCG. A significant finding was that the low work function value of Ag (−4.74 eV) at the (111) surface makes possible the transfer of electrons from CCG to Ag. Consequently, the degree of photodegradation by Ag/ZnO/CCG is much higher than the sum of photodegradations by Ag/ZnO and ZnO/CCG samples, which indicates that the combination of metal, CCG, and semiconductor provides enhanced photocatalytic activity through the double transference of electrons.