One-pot preparation of porous Cr2O3/g-C3N4 composites towards enhanced photocatalytic H-2 evolution under visible-light irradiation

摘要

Porous Cr2O3/g-C3N4 composites were prepared by a facile one-pot pyrolysis method and showed enhanced visible-light-driven photocatalytic H-2-evolution activities, with the highest rate 4.0 times of that for pure g-C3N4. During the one-pot process, accompanied by the pyrolysis of melamine to form g-C3N4, CrCl3 center dot 6H(2)O acted as Cr precursor to form Cr2O3, and meanwhile functioned as pore-forming agent to increase the surface area and pore volume of g-C3N4. The cocatalytic effect of Cr2O3 and the favorable textural properties of gC(3)N(4) promoted the separation of photogenerated charge carriers, facilitated the diffusion, accumulation and adsorption of reactants, enriched the reactive sites for redox reaction, and thus resulted in the enhanced photocatalytic activities. This work presented an effective route to simultaneously optimize the compositions and microano-structures of photocatalysts for H-2 evolution. (C) 2016 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.