Interfacial Mediation by Sn And S Vacancies of p‐SnS/n‐ZnIn₂S₄ for Enhancing Photocatalytic Hydrogen Evolution with New Scheme of Type‐I Heterojunction

Abstract

The construction of interfacial electric field (IEF) in semiconductor heterojunction is of great significance in boosting photocatalytic hydrogen evolution through efficient separation of photogenerated charge‐carriers. However, the exploitation of IEF in type‐I heterojunction has not been proposed for designing photocatalysts. Herein, based on the density functional theory prediction, p‐SnS with different work functions modulated by Sn‐vacancy are compounded with n‐ZnIn2S4 containing S‐vacancy to form type‐I heterojunction. The optimized SnS/ZnIn2S4 photocatalyst without co‐catalysts exhibits an impressive hydrogen evolution rate of 22.75 mmol g−1 h−1, 6.23 times of ZnIn2S4. Systematic investigations reveal that the interfacial Sn‐S bond acts as a transport channel that accelerates the interface charge‐carriers transfer under the promotion of IEF originating from the significant Fermi level difference. A large difference in the surface photovoltage signal of SnS/ZnIn2S4 and ZnIn2S4 is achieved from effective photogenerated charge‐carriers separation by IEF. The new p‐n type‐I scheme of SnS/ZnIn2S4 induced by the interfacial mediation can separate the photogenerated charge‐carriers, and retain the highly reductive electrons of ZnIn2S4 for hydrogen evolution, overcoming the disadvantage of reduction potential decline in the typical type‐I scheme. This study will afford a new theoretical basis for the achievement of high‐efficiency photocatalytic hydrogen evolution through interface modulation.

In situ construction of Ohmic/Schottky-type MoS2/Sv-ZnIn2S4/Cu(OH)2 dual-junction photocatalysts with enhanced water splitting into hydrogen generation activity

“…In addition, a large number of defects within the orange circle can be observed, potentially resulting from S v . 33,34 The energy dispersive spectrometer (EDS) mappings reveal that the CMO-0.6/ZIS samples consist of Zn, In, S, Cu, Mo and O elements (Fig. 1F).…”

Facet-Engineered Cu2O Microparticles on Graphitic Carbon Nitride Nanosheets as Z-Scheme Heterojunction Photocatalysts for Degradation of Tetracycline

“…This process leads to the creation of the BEF and band bending, which facilitate electron transmission in the direction of the electric field. The disparity in work function (Φ) between the semiconductors dictates the strength of the BEF, which governs both the effectual separation and the direction of charge transfer at the interface. , Figure b presents the diversity in work function (Φ) among the samples investigated. As the Fermi level shifts, this leads to the generation of BEF in different directions and with varying intensities.…”

Stannum vacancies at precise interface of 2D/2D g-C3N4/SnS S-scheme heterojunction boost up photocatalysis

“…1d displays the (111) plane of SnS's lattice spacing on g-C 3 N 4 /SnS-5 (CNS-5) composites, 0.283 nm. 35 As a result, the unique 2D/2D layer-by-layer structure of the CNS-5 nanocomposites may reduce the photogenerated carriers' (photogenerated electrons and holes) diffusion distance, significantly enhancing the photocatalytic performance for selective oxidation. The distribution states of C, N, S, and Sn in the CNS-5 composites show that SnS and g-C 3 N 4 are mixed, as observed from the elemental maps in Fig.…”