Preparation and photocatalytic properties of BNMT-BNNS/TiO2 hierarchical heterostructures

Abstract

A novel one-dimensional boron nitride and titanium oxide hierarchical heterostructures (BNMT-BNNS/TiO2) composite photocatalyst endowed with high specific surface area was synthesized by molten salt assisted annealing and sol-gel method. With the increase of TiO2 concentration, the photocatalytic degradation efficiency of BNMT-BNNS/TiO2 hierarchical heterostructures increased first and then decreases, while the adsorption tended to decrease. When the molar ratio of TiO2 to BNMT-BNNS was 27:50, BNMT-BNNS/TiO2 displayed a higher specific surface area of 79.6770 m2g-1 than that of TiO2 (19.810 m2g-1). The methylene blue photodegradation rate of BNMT-BNNS/TiO2 is 99.62% after 115 min ultraviolet irradiation, show 1.62 times higher than that of the synthesized pure TiO2. The positive synergistic degradation mechanism between the strong adsorption of BNMT-BNNS support and the excellent photocatalysis of TiO2 was also discussed in detail. This work reports the synthesis of BNMT-BNNS/TiO2 photocatalysts with high surface area, excellent photocatalytic performance and reusability. BNMT-BNNS/TiO2 has potential applications in practical environmental purification.