Facile one-pot synthesis of defective (001)-TiO2−x/h-BN photocatalyst for environmental applications

Abstract

Various factors control the photocatalyst efficiency including the lifetime of photogenerated charge carriers, photocatalyst surface energy, and light harvesting efficacy. In this study, the defective (001)-TiO2-x/h-BN composite was synthesized by a facile one-pot method to merge the fantastic features of the reactive metastable (001) facet and self-defects in TiO2 anatase crystals with the 2D h-BN. Pure anatase phase of TiO2 was obtained by the suggested preparation method, which contains ∼33 % of the exposed (001) facet. The predominancy of oxygen vacancy in TiO2 crystals was proved experimentally and theoretically by the DFT calculations. The defects in TiO2 along with the incorporated h-BN caused better light harvesting and longer charge lifetime. The prepared defective (001)-TiO2-x/h-BN was applied efficiently for NO removal with very limited release of the toxic NO2 by-product as an environmental application. The detected oxygen vacancy in TiO2 along with h-BN were found to play a synergistic enhancement for NO removal. However, more defects reduced the overall activity because of rapid oxidation of oxygen vacancies on surface of the photocatalyst. To sum up, the defective (001)-TiO2-x/h-BN composite can be considered as a promising material for environmental applications.