Growth of macroporous TiO2 on B-doped g-C3N4 nanosheets: a Z-scheme photocatalyst for H2O2 production and phenol oxidation under visible light

Abstract

The design and development of a highly robust catalyst for energy production and environmental abetment are gaining much attention in the field of visible-light-driven catalysis. This work demonstrates the fabrication of a series of hierarchical macroporous mixed-phase TiO₂ on the surface of B-doped g-C₃N₄ (BCN). The physicochemical properties such as crystallinity, morphology, chemical environment, and optical and electronic properties of the as-synthesized materials were analysed by using different analytical techniques. PXRD and HRTEM data revealed the growth of mixed-phase TiO₂ (anatase and rutile) on the BCN surface, mimicking P25 in the case of the best photocatalyst (TBCN-8). The catalytic activity of the as-synthesized materials was tested towards H₂O₂ production (110 μmol h⁻¹) and phenol oxidation (87% of 20 ppm phenol solution) under visible light. Higher photocurrent, lower impedance arc, and lower PL intensity suggest a lower electron–hole recombination rate in the case of TBCN-8, elucidating the best catalytic performance by the material. This work validates the facile fabrication of macroporous TiO₂/BCN nanocomposites and their visible-light-driven catalytic activity based on both the p–n heterojunction and Z-scheme mechanism.