The restricted charge transfer and slow oxygen evolution reaction (OER) dynamics tremendously hamper the realistic implementation of SnS2 photoanodes for photoelectrochemical (PEC) water splitting. Here, a novel strategy is developed to construct interfacial NCuS bonds between NC skeletons and SnS2 (CuNC@SnS2) for efficient PEC water splitting. Compared with SnS2, the PEC activity of CuNC@SnS2 photoelectrode is tremendously heightened, obtaining a current density of 3.40 mA cm2 at 1.23 VRHE with a negatively shifted onset potential of 0.04 VRHE, which is 6.54 times higher than that of SnS2. The detailed experimental characterizations and theoretical calculation demonstrate that the interfacial NCuS bonds enhance the OER kinetic, reduce the surface overpotential, facilitate the separation of photon‐generated carriers, and provide a fast transmission channel for electrons. This work presents a new approach for modulating charge transfer by interfacial bond design in heterojunction photoelectrodes toward promoting PEC performance and solar energy application.

The main obstacles to the photocatalytic reduction of nitrogen are the low separation efficiency of photogenerated charges and the few activation sites for nitrogen. It is highly desirable to explore new strategies for improving the nitrogen fixation performance of catalysts. Herein, the Bi metal active sites are constructed on the surface of BiOBr/BiOI heterojunction by in situ reaction, which promote the absorption, activation, and dissociation of nitrogen molecules. Moreover, the existence of Bi metal and BiOBr/BiOI heterojunction enhances the light absorption ability and facilitates the separation and transfer of photogenerated charges. The theoretical calculation also demonstrates that the BiOBr/BiOI/Bi composite has excellent electron structure and electron transfer efficiency. So, the ternary BiOBr/BiOI/Bi catalyst shows excellent performance of photocatalytic reduction of nitrogen to ammonia. The nitrogen reduction rate is 221.9 μmol g−1 h−1, which is 7.6 and 5 times higher than that of pure BiOBr and BiOBr/BiOI. The mechanism of photocatalytic nitrogen fixation of the BiOBr/BiOI/Bi is proposed based on the experimental and theoretical results. This study provides a novel method for improving the photocatalytic nitrogen reduction performance of catalysts.

The construction of close contact heterojunction structures is crucial to modify photocatalytic performance. Here a series of heterojunction ZnIn 2 S 4 /CNTs/ZnS nanocomposites for photocatalytic hydrogen evolution were synthesized by a simple thermal reflux approach. The ideal ZnIn 2 S 4 /CNTs/ZnS sample has a photocatalytic hydrogen evolution rate of 0.9363 mmol • g À 1 • h À 1 with favorable cycle stability, which is about 16.9 and 5.5 times that of pure ZnIn 2 S 4 and binary ZnIn 2 S 4 /ZnS. The tight interfacial contact between ZnIn 2 S 4 , ZnS, and CNTs raises photogenerated charge carrier separation efficiency. CNTs have a high electrical conductivity, which allows them to receive and transport photogenerated electrons effectively. Therefore, the recombination of photon-generated charges may be efficaciously restrained, and the accepted electrons can be rapidly transported to reactive sites for production of hydrogen. Simultaneously, density functional theory (DFT) simulations show that introducing CNTs can enhance electronic characteristics and add additional charge carriers. This study shows that well-designed CNTs-based heterojunction structure can effectively promote charge separation in photocatalysis.

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The addition of carbon materials to semiconductor catalyst systems can boost the activity of photocatalytic H2 production substantially. Herein, we prepared a series of carbon nanotube/ZnIn2S4 (CNT/ZIS) composites with different contents of CNTs through a simple hydrothermal process and investigated the effect of CNTs on hydrogen evolution performance of ZIS in detail. The electron–hole behavior of CNT/ZIS is studied by photocurrent density, linear sweep voltammetry, steady state, and transient fluorescence spectra. Meanwhile, its optical properties have been studied. Comprehensive experimental characterization and theoretical research reveal that CNTs can not only enhance the visible-light absorption property of composite materials but also efficiently separate the photoinduced carriers and supply more active sites. In consequence, CNT/ZIS exhibits superior photocatalytic H2 evolution. The optimal sample has a hydrogen production rate of 8904.2 μmol·g–1·h–1 under visible-light irradiation, which is 13.2 times higher than that of bare ZIS. Our work offers a simple, cheap, and green method for improving the photocatalytic performance of photocatalysts toward practical applications.