Controlled synthesis of g-C3N4@BiPO4 core–shell nanorods via low temperature reassembled strategy

Abstract

The g-C3N4@BiPO4 nanorod core–shell structure photocatalysts were prepared by a new neutral hydrothermal reaction system combined with low temperature reassembled strategy. The CN precursors were successfully reassembled on the surface of BiPO4 nanorod to form ultrathin g-C3N4 layer (about 1 nm) under low temperature. Due to the formation of the core–shell structure, it can effectively promote the separation of photogenerated charge, thereby greatly improving the photocatalytic activity under UV light irradiation. The photodegradation activity of the phenol by the g-C3N4@BiPO4 nanorod core–shell structure photocatalyst annealing at the optimized conditions exhibits 1.6 times that of pure BiPO4 nanorod. The relationship between core–shell structure and photocatalytic activity under UV light irradiation was profoundly revealed through a comprehensive contrast experiment, and the mechanism of the enhancement activity of core–shell structure photocatalyst was also explored. It was found and detailedly demonstrated that the CN precursors prepared by neutral hydrothermal reaction can be polymerized into graphite-like phase C3N4 on the surface of Bi-based photocatalytic materials via low temperature thermal catalytic reassembled method. The novel method was proved to be a universal method for construction of core–shell structures. The establishment of g-C3N4@BiPO4 core–shell structure can provide blueprints for the construction of other organic–inorganic interface electric field catalytic system and can greatly improve the attractive prospect in practical applications owing to the perfect photocatalytic performance. Keywords: Core–shell structure, Interface photocatalysis, Ultrathin g-C3N4, BiPO4 nanorod