Highly efficient photocatalytic degradation of refractory organic pollutants onto designed boron nitride: Morphology control and oxygen doping

Abstract

Hexagonal boron nitride (h-BN) exhibits enormous potential for photocatalysis, while its performance is restricted by insufficient light absorption and rapid electron-hole pairs recombination. To address this, BN photocatalysts with various morphologies and oxygen doping were rationally prepared in this study. The results showed that band gap control and charge transfer ability regulation were achieved by oxygen doping and morphology designing. The optimized BN photocatalysts (s-BN) with 3D hierarchical spherical-like structure presented an ultra-thin edge, high oxygen content (6.1 at%), and high specific surface area (446 m2g−1), resulting in enhanced light absorption, efficient charge transfer, and abundant surface reactions. The photocatalytic tetracycline degradation efficiency and rate constant of s-BN were 18.11 times and 51.02 times higher than that of commercial h-BN, respectively. The mechanism study identified the primary active species for s-BN as superoxide radicals and holes, which facilitated the mineralization of tetracycline during the degradation process. This study provides a novel strategy for the development of high-performance and stable BN photocatalysts for efficient photocatalytic degradation of refractory organic pollutants.