Construction of three-dimensional mesoporous carbon nitride with high surface area for efficient visible-light-driven hydrogen evolution

Abstract Carbon nitride, as an outstanding photocatalyst for hydrogen production, displays a limited photocatalytic performance on account of the insufficient light absorption and low surface area. Herein, three-dimensional mesoporous carbon nitride with large surface area was prepared by using freeze-dried cyanuric acid-melamine supramolecular aggregates and ionic liquid as precursor and template, respectively. The results find that as-prepared carbon nitride materials possess the 3D interconnected open-framework with porous channels owing to the decomposition of ionic liquid and precursor under high temperature calcination, which in favor of the contact between active sites and reactants as well as the improvement of charge carrier transport rate. Compared to the pure carbon nitride, the obtained CNF-0.005 was endowed with the ultrathin nanosheets, broaden light adsorption, high separation rate of photogenerated carriers and improved photocatalytic activity. Especially, the above-mentioned sample exhibits a superior visible light driven photocatalytic H2 production capability and excellent durability, as high as 129.5 μmol/h, which is about 27.6 times and 1.8 times than that of the bulk CN and pure CNF, respectively. This work opens up an ingenious strategy towards the fabrication of high-performance carbon nitride with controllable structure and improved surface area for efficient hydrogen production.