Chemically bonded interface modulated S-scheme charge transfer on Sb2S3@ZnIn2S4 core-shell heterostructures for boosted catalytic activity toward nitrogen photofixation

Abstract

The explore of efficient strategies for nitrogen photofixation driven by visible light at room temperature and atmospheric pressure is still highly desirable until now but remains a great challenge. In this study, hierarchical Sb2S3@ZnIn2S4 core-shell samples were synthesized through a hydrothermal reaction, in which ultrathin ZnIn2S4 nanosheets were tightly and uniformly wrapped on the surface of Sb2S3 nanorods. Systematic characterization revealed that the chemically bonded interface in Sb2S3@ZnIn2S4 core-shell heterostructures was critical to the speedy charge separation, and then gave rise to significant enhancement of photocatalytic performance for nitrogen photofixation. The optimal nitrogen photofixation system, namely, Sb2S3@ZnIn2S4-75, exhibited excellent performance with produced ammonia concentration of 15.96±0.97 mg·L‒1 after visible light irradiation for 40 min, which was approximately 1.88 and 7.19 times higher than those of relevant ZnIn2S4 and Sb2S3, respectively. Moreover, a S-scheme charge transfer route on Sb2S3@ZnIn2S4 core-shell heterostructures was proposed based on the band structures analysis, in situ irradiated X-ray photoelectron spectroscopy (ISI-XPS) investigation, noble metal deposition, and density functional theory (DFT) simulation. This work gave a useful insight into the development of efficient photocatalysts for boosted photocatalytic activity toward nitrogen photofixation.