Construction of Mn-Defective S/MnCdS for Promoting Photocatalytic N Reduction.

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/MnCdS (S/0.4MCS) composite. To optimize the photocatalytic performance in N 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 N 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.