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As a renewable green energy, hydrogen has received widespread attention due to its huge potential in solving energy shortages and environment pollution. In this paper, a one-step solvothermal method was applied to grow ultra-thin g-C 3 N 4 (UCN) nanosheets and NiS nanoparticles on the surface of ZnIn 2 S 4 (ZIS). A ternary NiS/ZnIn 2 S 4 /ultra-thin-g-C 3 N 4 composite material with dual high-speed charge transfer channels was constructed for the advancement of the photocatalytic H 2 generation. The optimal ternary catalyst 1.5wt.%NiS/ZnIn 2 S 4 /ultra-thin-g-C 3 N 4 (NiS/ZIS/UCN) achieved a H 2 evolution yield reached to 5.02 mmolg -1 h -1 , which was 5.23 times superior than that of pristine ZnIn 2 S 4 (0.96 mmolg -1 h -1 ) and even outperform than that of the best precious metal modified 3.0 wt%Pt/ZnIn 2 S 4 (4.08 mmolg -1 h -1 ). The AQY at 420 nm could be achieved as high as 30.5%. The increased photocatalytic performance of NiS/ZIS/UCN could be ascribed to the type-I heterojunctions between intimated ZIS and UCN. In addition, NiS co-catalyst with large quantity of H 2 evolution sites, could result in efficient photo-induced charges separation and migration. Furthermore, the NiS/ZIS/UCN composite exhibited excellent H 2 evolution stability and recyclability. This work would also offer a reference for the design and synthesis of ternary co-catalyst with heterojunction composite for green energy conversion., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Inc. All rights reserved.)

S-scheme heterostructure can facilitate the separation of carriers while maintain outstanding redox capacity. A series of ternary Bi 7 O 9 I 3 /g-C 3 N 4 /Bi 3 O 4 Cl photocatalytic system was triumphantly synthesized via oil bath method in this work and used in photocatalytic degradation of phenol. The optimal TOC removal rate reached up to 93.57% under illumination for 160 min, which was slightly lower than phenol photodegradation (about 100%, 100 min). Correspondingly, the apparent rate constants for the decay of phenol are determined to be 0.0211 min -1 . The experiment of free radical capture indicated that ·OH and ·O 2 - were the major oxidizing substances to degrade phenol. The products of phenol photodegradation were identified by high performance liquid chromatography (HPLC) and a possible degradation pathway was proposed. The characterization analysis and density functional theory (DFT) calculations demonstrated that dual S-scheme charge migration was generated at the interface of Bi 7 O 9 I 3 , g-C 3 N 4 and Bi 3 O 4 Cl, contributing to an efficient separation of light-excited carriers. In the field of environmental remediation, the discovery of this work could open up promising vistas for designing bismuth-based ternary heterostructures with application potentiality., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Promoting the separation of photogenerated electron-hole pairs and enhancing the charge carrier transfer are critical in photocatalysis. In our work, a ball-flower-like NiS/Zn 3 In 2 S 6 /g-C 3 N 4 photocatalyst fabricated by a hydrothermal method exhibited superior performance for photocatalytic water splitting. The optimized 2.0% NiS/Zn 3 In 2 S 6 /g-C 3 N 4 rivaled noble metal based Pt/g-C 3 N 4 and showed an apparent quantum efficiency (AQE) of 24.3% at 420 nm, with a H 2 yield of 4.135 mmol g -1 h -1 , which was 30.4 and 9.51 times that of pure g-C 3 N 4 and binary Zn 3 In 2 S 6 /g-C 3 N 4 composites, respectively. The experimental and characterization results suggested that the heterojunction formed between Zn 3 In 2 S 6 /g-C 3 N 4 and the decorating NiS co-catalyst cooperatively suppressed the electron-hole recombination and facilitated the charge carrier transfer, thus resulting in significant improvement of the H 2 evolution performance. Moreover, the increased specific surface area and the enhanced visible-light absorption also contributed to superior water splitting performance. The prepared ternary catalytic system with the heterojunction and non-noble metal co-catalyst has great potential as an alternative to noble metals for achieving cost-efficient water splitting systems.

Photocatalytic hydrogen evolution can effectively alleviate the troublesome global energy crisis by converting solar energy into the chemical energy of hydrogen. In order to realize efficient hydrogen generation, a variety of semiconductor materials have been extensively investigated, including TiO 2 , CdS, g-C 3 N 4 , metal-organic frameworks (MOFs), and others. In recent years, to achieve higher photocatalytic performance and reach the level of large-scale industrial applications, photocatalysts decorated with transition metal phosphides (TMPs) have shone brightly because of their low cost, stable physical and chemical properties, and substitution for precious metals of TMPs. This Review highlights the preparation methods and properties associated with photocatalysis of TMPs. Moreover, the H 2 generation efficiency of photocatalysts loaded with TMPs and the roles of TMPs in catalytic systems are also studied systematically. Apart from being co-catalysts, several TMPs can also serve as host catalysts to boost the activity of photocatalytic composites. Finally, the development prospects and challenges of TMPs are put forward, which is valuable for future researchers to expand the application of TMPs in photocatalytic directions and to develop more active photocatalytic systems., (© 2020 Wiley-VCH GmbH.)