An insight to band-bending mechanism of polypyrrole sensitized B-rGO/ZnFe2O4 p-n heterostructure with dynamic charge transfer for photocatalytic applications

Developing a highly desirable multicomponent photocatalytic system for environmental remediation and water splitting is needed for current societal development. A visible active B-rGO/ZnFe2O4 photocatalyst was synthesized through the hydrothermal process, further magnify its electronic properties, the binary hybrid is modified with polypyrrole. The designed ternary hybrid utilizes the combining benefits of photo-sensitizer and interfacial charge transfer mechanism that ultimately boost its photocatalytic efficiency. The estab-lishment of interfacial p-n heterojunction via band-bending mechanism between B-rGO (BG) nanosheets and ZnFe2O4 (ZnF) nanoparticles was validated from photo-density in the opposite direction and upturned V-shaped Mott-Schottky plots. It was observed that 2BG/ ZnF@20PPY exhibits the best activity i.e., 100% reduction of 50 ppm Cr (VI) in 45 min and H2-production of 598 mmolh-1. Effective charge separation in 2BG/ZnF@20PPY is well sup -ported by PL, TRPL, EIS, transient-photocurrent, and donor density calculations. The strong contact among the constituents in 2BG/ZnF@20PPY is well-correlated with XPS and Raman characterization. (c) 2021 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.