Construction of charge transfer channels inside h-BN/ g-C3N4 composites to enhance photocatalytic activity

Water resources are an indispensable part of life, but the current water pollution problem is facing serious challenges. In this article, two-dimensional g-C3N4 and h-BN used as raw materials, a series of h-BN/g-C3N4 (BCN) composite catalysts with varying mass by designed and synthesized using combination of simple solvent volatilization and high-temperature thermal polymerization method. The degradation rate of the BCN-2 catalyst was impressively 13.7 times higher than that of the bulk g-C3N4 when RhB was used as the target pollutants, demonstrating significantly enhanced photocatalytic performance compared to both bulk g-C3N4 and h-BN. The burst experiments on free radicals revealed that h+ and ∙O2− played a predominant role in the photocatalytic system. Moreover, the introduction of h-BN into g-C3N4 nanosheets modulated their microstructure, facilitating effectively hole migration channels and enhancing synergistically the separation efficiency of photogenerated electron-hole pairs. Consequently, the composites of h-BN/g-C3N4 with remarkably enhanced photocatalytic activity were obtained.