▎ 摘　　要

The nanocomposite film including polyoxometalate (POM) cluster K28Li5H7P8W48O184 center dot 92H(2)O (P8W48), reduced graphene oxide (rGO) and Au nanoparticles (Au NPs) was successfully fabricated by electrochemical reduction assisted technique. This synthesis was novel, convenient, and environmentally friendly. Moreover, the time of fabricating process was greatly shorten to about 1 h comparing to that of the traditional method of layer by layer (LbL) self-assembly. The reduced P8W48 was served as reducing agent, stabilizer and bridging molecules simultaneously in the composite film. The structure of the composite material was verified by comprehensive characterization using scanning electron microscopy, transmission electron microscopy, and X-ray photoelectron spectroscopy. The investigation of the electrocatalysis for H2O2 showed that the {PEI/rGO}-Au@P8W48 modified electrode has high catalytic activity, good sensitivity, good selectivity, low detection limit and fast response. In addition, the result indicated that the electrocatalytic activity of the electrode with Au NPs was better than that of the electrode without Au NPs. The enhanced catalytic property was attributed to the synergistic effect of the rGO, P8W48 and Au NPs. (C) 2019 Elsevier Ltd. All rights reserved.