International Journal of Hydrogen Energy, Vol.45, No.41, 21442-21449, 2020
CuWO4 decorated by polypyrrole (PPy) protector/sensitizer for novel photocatalytic and stable water splitting for hydrogen generation
Herein, we used polypyrrole (PPy), a conducting polymer, to decorate on CuWO4 to boost its photocatalytic activity. Then, the synthesized PPy decorated on CuWO4 (PPy/CuWO4) materials were applied to photocatalytically split water to produce hydrogen. The study investigated that the used PPy effectively served as a spring-board (sensitizer) to improve charge (e(-) and h(+)) separation of the CuWO4 photocatalyst. The used PPy also effectively increased Fermi level of these separated e(-) of the CuWO4. Thus, the PPy/CuWO4 generated large available and strong charges, which effectively split water to generate hydrogen. The optimal PPy decorating content for the highest water splitting efficiency is shown to be 4 wt%. Above the optimal decorating content, these excess PPy covered more CuWO4 surface preventing incident irradiation reaching to the material leading to decrease in photocatalytic efficiency. The H-2 generation from photocatalytic water splitting by the 4PPy/CuWO4 were 365 (mu mol. g(-1)cat. h(-1)). It is further observed that the used PPy, which completely covered the CuWO4 particles, effectively assisted charge transfer for their rapid travel to the polymer surface. Thus, the used PPy successfully prevented contact between charges and CuWO4 to protect the material from self-photocorrosion through water splitting process. (C) 2020 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.