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 CuWO 4 to boost its photocatalytic activity. Then, the synthesized PPy decorated on CuWO 4 (PPy/CuWO 4) 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 CuWO 4 photocatalyst. The used PPy also effectively increased Fermi level of these separated e− of the CuWO 4. Thus, the PPy/CuWO 4 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 CuWO 4 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/CuWO 4 were 365 (μmol. g−1cat. h−1). It is further observed that the used PPy, which completely covered the CuWO 4 particles, effectively assisted charge transfer for their rapid travel to the polymer surface. Thus, the used PPy successfully prevented contact between charges and CuWO 4 to protect the material from self-photocorrosion through water splitting process. Image 1 • Successfully decorated PPy on CuWO 4 to enhance its photocatalytic performance. • PPy effectively served as a sensitizer to improve charge separation of the CuWO 4. • PPy also effectively increased Fermi level of these separated e- of the CuWO 4. • PPy/CuWO 4 exhibited novel photocatalytic water splitting for hydrogen production. • Optimal PPy decorating content for the highest water splitting efficiency was 4 wt%. [ABSTRACT FROM AUTHOR]