A facile and scalable route for synthesizing ultrathin carbon nitride nanosheets with efficient solar hydrogen evolution

Abstract

Two-dimensional (2D) graphene-like carbon nitride nanosheets (CN-S) with unique photoelectronic properties have received much attention in advanced photocatalysis applications. The challenge for the synthesis of this promising 2D metal-free nanomaterials is to develop a facile but scalable strategy. Herein we for the first time reported a feasible approach to prepare the few-layered CN-S by introduction urea as “bubble template” in the thermal polymerization process. Compared to the bulk carbon nitride (CN-B), the thin-layered CN-S with a thickness of around 4 nm possessed the large specific surface area, enlarge electronic-band structure, fast photogenerated electron-hole transfer capability, and increased charge lifetime. Eventually, the resulting CN-S not only had a relatively high yield of 44.5%, but also exhibited a superior photocatalytic hydrogen evolution activity (1400 μmol g-1 h-1) from water under visible-light irradiation (λ > 420 nm). This work highlights a cost-effective and strategy towards the one-step and large-scale production of high-performance CN-S photocatalysts for efficient solar-to-fuel conversion.