“…Among various graphene-based hetero-architectures, the graphene/inorganic semiconductor contacts have attracted much attention because of their ample potential for high-performance Schottky photodiodes (PDs) [4]. For example, the enhanced photoresponse characteristics with high sensitivity and fast response were demonstrated on various graphene-based Schottky PDs that were composed of typical inorganic semiconductor materials (e.g., Si [5,6], Ge [7], GaAs [8,9], CdSe [10], ZnO [11,12,13,14,15,16,17,18,19,20,21], etc.). Among them, ZnO is one of the most prospective materials for high-performance ultraviolet (UV) PDs because of its wide band gap and excitonic properties [22,23].…”