Large-scale production of ultrathin carbon nitride-based photocatalysts for high-yield hydrogen evolution

Abstract

Although two-dimensional graphitic carbon nitride (2D g-C3N4) and corresponding heterostructures have been widely synthesized for photocatalysis, it is still challenging to obtain 2D g-C3N4 at large-scale and also achieve high quantum efficiency. Here we report a subtractive manufacturing method mediated by Nb2O5 to mass-produce high quality Nb2O5/2D g-C3N4 and pure 2D g-C3N4. Nb2O5/2D g-C3N4 and 2D g-C3N4 both show efficient photocatalytic hydrogen evolution performance, in which the optimal Nb2O5/2D g-C3N4 exhibits high external quantum efficiency (50.65 % and 14.75 % at 405 nm and 420 nm). The origin of the high efficiency can be ascribed to two aspects: (i) nanostructure engineering forming 2D structure can shorten the charge migration distance; (ii) Nb2O5/2D g-C3N4 with strong electric coupling can further accelerate the charge transfer driven by the built-in electric field formed in Type II heterostructure. This work presents a case study to realize high-yield synthesis and high catalytic performance simultaneously over g-C3N4.