Synergy of dopants and porous structures in graphitic carbon nitride for efficient photocatalytic H2 evolution

Abstract

Modification of the environmentally-friendly non-metallic polymer semiconductor graphite carbon nitride (g-C3N4) has been a research hotspot in the field of photocatalysis, and is regarded as a pivotal solution to energy problems. Nevertheless, the bottlenecks of a slow carrier separation rate, limited visible light absorption and weak water reduction driving force have not been effectively solved due to uneven mass and heat transfers during high-temperature calcination; therefore, no carbon nitride photocatalysts with excellent properties can be provided. Recently, optimizing the modification with multiple methods has become an important research direction. To generate better photocatalysts, we propose a facile copolymerization strategy by combining doping and pore formation to inhibit the agglomeration and efficiently optimize the surface properties and external structure of the catalyst, thereby improving its photocatalytic performances. The amended g-C3N4 produces a broadened visible-light response, a larger surface area, and reformative separate efficiency of charge carriers. Thus, the effectively-modified g-C3N4 has enhanced H2 production, which is 6.3-fold greater than that of pristine carbon nitride.