Fig. 1.

Structures of the as-prepared plasmonic electrode and photoelectrochemical system. a SEM and AFM images. b The height profile of the as-prepared Au nanoelectrode array along the gray line in AFM image of a. c The UV-Vis distinction spectrum detected by the specular reflection mode in air and in 0.2 M sodium sulfate solution. d Schematic of the three-electrode electrochemical system used in the experiments, including working electrode (WE), counter electrode (CE) and reference electrode (RE). e Schematic of photoelectrochemical characterization under the chopped light. The scale bars in a are 1 μm. The area of the gold nanoelectrode array is 0.8 cm². The numbers in e represent different times