Rational design of donor-acceptor structured tubular carbon nitride modulates charge distribution for photocatalytic hydrogen evolution

Photocatalysis is one of the most promising technologies for solving environmental and energy problems, but current photocatalysts still suffer from low visible light utilization and insufficient photogenerated charge separation efficiency. Therefore, in this work, D-A tubular materials with tubular carbon nitride (TCN) as electron donor (D) and 2-mercaptobenzothiazole (BZ) as electron acceptor (A) were constructed by molecular doping and modulation of the carbon nitride geometry. It was shown that the introduction of BZ could modulate the electronic structure of the catalyst, promote electron migration from TCN to BZ, and inhibit the recombination of photogenerated electrons and holes. Meanwhile, the ultra-thin tubular structure could expose more active sites. In addition, the adsorption of protons by BZ-TCN was further improved due to the modulation of the charge distribution between the components by the introduction of small molecules. Among them, the photocatalytic hydrogen production rate of BZ 0.1 -TCN was twice that of TCN. The in-depth discussion of the components through theoretical calculations and characterization tests contributes to the understanding of the mechanism of photocatalytic hydrogen production.