Construction and preparation of novel 2D metal-free few-layer BN modified graphene-like g-C₃N₄ with enhanced photocatalytic performance

Novel two-dimensional (2D) metal-free few-layer BN/graphene-like g-C₃N₄ (2D BN/g-C₃N₄) composites have been synthesized by a simple hydrothermal method. The construction of a 2D/2D structure between BN and g-C₃N₄ could shorten the migration distance of charge transfer, and provide a large contact surface. By introducing few-layer BN nanosheets into g-C₃N₄, the as-prepared 2D BN/g-C₃N₄ composites exhibited a much enhanced photocatalytic performance than that of pure g-C₃N₄. The 0.5% 2D BN/g-C₃N₄ composite possessed the most wonderful ability towards Rhodamine B (RhB) degradation irradiated by visible light, which could achieve a highest degradation efficiency of 98.2% within 120 min. Further studies revealed that modifying g-C₃N₄ with few-layer BN could not only facilitate the separation and transfer of photo-induced holes and electrons, but also exposed the fact that the (002) facet edges of BN terminated with -OH groups could act as catalytic sites, and thus enhance the photocatalytic activities. Moreover, the successful preparation of 2D BN/g-C₃N₄ composites may pave the way for fabricating other 2D composites with a layer-by-layer architecture.