Directed Inward Migration of S-Vacancy in BiS QDs for Selective Photocatalytic CO to CHOH.

The directional migration of S-vacancy is beneficial to the separation of photogenerated carriers and the transition of electrons in semiconductors. In this study, Bi/BiS@carboxylic-cellulose (CC) photocatalyst with bionic chloroplast structure is obtained by electron beam irradiation to induce S-vacancy in BiS@CC. The results of CO photoreduction experiments demonstrate that the reduction rate of CO to CHOH by Bi/BiS@CC-450 samples is 10.74 µmol·g·h, and the selectivity is 92.82%. The results show that the inward migration behavior of the borderline S-vacancy (b-S) induces the redistribution of electrons in Bi/BiS@CC. The Bi° clusters in Bi/BiS@CC is conducive to adsorb CO, and the internal S-vacancy (i-S) is conducive to adsorb CHOH, which accelerate the transfer of gas-phase products to realize the controllable conversion of CO and photoreduction products at the gas-liquid-solid three-phase interface. This study provides a new idea for the development and utilization of green photocatalysts in clean energy.