Mesoporous carbon nitride based nanomaterials for solar fuel production

From economic and environmental aspects, the generation of hydrogen (H2) from renewable solar energy and water through photocatalytic water splitting is a promising route, but the development of an efficient catalyst remains a great challenge for its technological use on a large scale. Because of several features like being metal-free, nontoxic, low cost, and chemically stable, carbon nitride has attracted worldwide attention. Compared to bulk carbon nitride, mesoporous carbon nitride (MCN) possesses a higher surface area and plentiful accessible mesopores. For the first time, Co3O4/MCN nanocomposites were designed and synthesised for photocatalytic H2 evolution in this work. Co3O4,earth-abundant nanoparticles, were supported on MCN via an impregnation method. Complementary characterisation techniques were employed to understand the properties of the fabricated catalysts.The bare MCN prepared under optimum conditions showed high photocatalytic activity under visible light irradiation without using any co-catalyst. The Co3O4/MCN with a Co3O4 mass content of 5 wt% exhibited the optimum photocatalytic activity in H2 evolution, which was two times higher than that of the bare MCN. The improved photocatalytic performance may be attributed to the enhanced catalytic properties, visible-light harvesting and effective charge separation.