▎ 摘　　要

Graphene/semiconductor hybrid photodetectors have attracted much attention recently for their excellent optoelectronic properties. However, high background current and 1/f noise limit their sensitivity. In this paper, the phenomenon of photo-induced quantum capacitance was found based on the transfer-free graphene/Cu2O/Cu structure. Under illumination, the Fermi level in graphene can be modulated by the photogenerated holes trapped in Cu2O nanoparticles, which causes the capacitance response phenomenon. The maximum capacitance response of 10(4) F/W with the minimum detectable light power of 5.3 fW was achieved at room temperature. (C) 2022 Author(s).