AUTHOR=Bao Yayan , Chen Zezhong , Wang Yuzhen , Liu Lizhen , Wang Haiyan , Li Zuopeng , Feng Feng 

TITLE=Co-assembly of graphene/polyoxometalate films for highly electrocatalytic and sensing hydroperoxide

JOURNAL=Frontiers in Chemistry

VOLUME=11

YEAR=2023

URL=https://www.frontiersin.org/journals/chemistry/articles/10.3389/fchem.2023.1199135

DOI=10.3389/fchem.2023.1199135

ISSN=2296-2646

ABSTRACT=<p>Graphene oxide (GO) films mixed with polyethylenimine (PEI) were prepared by a layer-by-layer assembly (LBL) method, in which the GO component is then converted to reduced GO (rGO) <italic>in situ</italic> through an electron transfer interaction with a polyoxometalate (POM) that is assembled on the outer surface. With this, devices were manufactured by spreading composite films of (PEI/rGO)<sub>n</sub>-POM with different numbers of PEI/rGO layers on ITO substrates. Cyclic voltammetry (CV) reveals that the catalytic activity for H<sub>2</sub>O<sub>2</sub> of (PEI/rGO)<sub>n</sub>-POM films was significantly higher than that of similar films of (PEI/GO)<sub>n</sub>/PEI/POM manufactured LBL with the same number of layers, although the catalyst POM content of (PEI/rGO)<sub>n</sub>-POM was only half that of (PEI/GO)<sub>n</sub>/PEI/POM. The catalytic activity of (PEI/rGO)<sub>n</sub>-POM films first increases and then decreases as the number of PEI/rGO layers increases. The result shows that (PEI/rGO)<sub>3</sub>-POM films with three PEI/rGO layers exhibit the highest efficiency. Amperometric measurements of the (PEI/rGO)<sub>3</sub>-POM films showed improved current response, high sensitivity, wide linear range, low detection limit, and fast response for H<sub>2</sub>O<sub>2</sub> detection. The enhanced catalytic property of (PEI/rGO)<sub>n</sub>-POM films is attributed to the electron transfer interaction and electrostatic interaction between POM and rGO.</p>