Construction of Mn-Defective S/Mn0.4Cd0.6S for Promoting Photocatalytic N2 Reduction

Abstract

Improving catalytic performance by controlling the microstructure of materials has become a hot topic in the field of photocatalysis, such as the surface defect site, multistage layered morphology, and exposed crystal surface. Due to the differences in the metal atomic radius (Mn and Cd) and solubility product constant (MnS and CdS), Mn defect easily occurred in the S/Mn_0.4Cd_0.6S (S/0.4MCS) composite. To optimize the photocatalytic performance in N₂ fixation, the effects of the synthesis conditions and reaction conditions for S/0.4MCS were explored and systematically studied. Combined with the experimental characterization and theoretical calculation, not only the photocatalytic reaction pathway but also the key steps of N₂ reduction were explored. Moreover, the transfer mechanism of photogenerated charge carriers (PCCs) formed between S and 0.4MCS was studied, which enhanced the utilization rate of photogenerated electrons (e^–) and holes (h⁺). This work detailedly discusses the relationship between microstructure and photocatalytic performance, which is beneficial for the design of efficient photocatalyst.