▎ 摘　　要

In contrast to the many studies employing heavy-metal-containing semiconductors in state-of-the-art photo-electrochemistry, this work presents the first use of graphene oxide (GO) for advanced cathodic PEC analysis. The bioinspired redox reaction between GO and dopamine (DA) led to the formation of reduced GO (RGO) and the simultaneous deposition of the electron acceptor poly(dopamine) on RGO. This greatly stimulated the cathodic photocurrent of the GO-modified indium tin oxide (ITO) (ITO/GO) electrode, making it possible to detect DA rapidly and sensitively through a split photoelectrochemistry strategy (i.e. the reaction between the analyte and the photoelectrode and the recording of the photocurrent signal are conducted in separate devices). This study indicates the great promise of GO by demonstrating an elegant sensing strategy involving an in situ redox reaction followed by PEC analysis. It is hoped that this may open up the exploration of carbon nanomaterials for innovative cathodic photoelectrochemistry in the future.