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Solar-driven water splitting offers a leading-edge approach to storing abundant and intermittent solar energy and producing hydrogen as a clean and sustainable energy carrier. More importantly, constructing well-designed photocatalysts is a promising approach to develop clean hydrogen energy. In this paper, flower spherical UiO-66-(SCH3)2/ZnIn2S4 (UiOSC/ZIS) photocatalysts are successfully synthesized by a simple two-step hydrothermal method, and they exhibit high hydrogen production activity in light-driven water splitting. The optimized 30-UiOSC/ZIS (the content of UiOSC was 30 mg) composite exhibits optimal hydrogen production activity with a hydrogen production of 3433 μmol g−1 h−1, which is 5 and 235 times higher than that of pure ZIS and UiOSC, respectively. In addition, a long-cycling stability test has shown that the UiOSC/ZIS composite has good stability and recyclability. Experimental and characterization results show the formation of a type-II heterojunction between UiOSC and ZIS. This effectively suppresses the recombination of electrons–holes and promotes the carrier transfer, thus significantly improving the hydrogen production performance. This research further promotes the application of UiO-66-(SCH3)2 in the field of photocatalytic hydrogen production and provides a reference for the rational design of UiO-66-based composite photocatalysts. [ABSTRACT FROM AUTHOR]

The UiO-66 family shows promising photocatalytic prospects in water splitting for hydrogen evolution under visible light irradiation due to its suitable band gap and adequate active sites. In this work, novel Ni2P/UiO-66-(SCH3)2 composites were prepared by a simple solvothermal method. These as-synthesized samples were fully characterized by XRD, SEM, TEM, HRTEM, EDS, and XPS methods. The effectiveness of visible light driven photocatalytic water-splitting to produce hydrogen was investigated in the presence of sacrificial agents. The results showed that the optimal hydrogen yield of 5 wt% Ni2P/UiO-66-(SCH3)2 is 3724.22 μmol g−1 h−1, reaching almost 187 times that of pristine UiO-66-(SCH3)2 (19.93 μmol g−1 h−1). Meanwhile, long term cycling stability tests also showed that Ni2P/UiO-66-(SCH3)2 composites present an excellent photocatalytic H2 production stability. Photoelectrochemical performance analysis revealed that the high catalytic activity of the composite materials could be associated with the synergistic effect of UiO-66-(SCH3)2 and Ni2P. Light stimulates UiO-66-(SCH3)2 to generate electrons and holes, and Ni2P as a cocatalyst could effectively transmit electrons and boost photogenerated charge separation. This work provides a reference for exploring UiO-66 family catalysts with good catalytic activity. [ABSTRACT FROM AUTHOR]

It was thought that the organic–inorganic hybrid perovskite MAPbI3 could be used to collect visible light for the photocatalytic hydrogen evolution reaction (HER). However, its ability to generate H2 is limited. Herein, we synthesized amorphous NiCoB through a redox method and coupled it with MAPbI3 to form the NiCoB/MAPbI3 composite photocatalyst by electrostatic self-assembly. 30% NiCoB/MAPbI3 exhibited the maximum H2 generation yield of 2625.57 μmol g−1 h−1, which was approximately 114 fold that of pristine MAPbI3 and much better than that of Pt/MAPbI3. In addition to the excellent photocatalytic HER capability, NiCoB/MAPbI3 maintained good stability in the 24 h cycling hydrogen evolution experiment. The photoelectric analysis showed that NiCoB as a cocatalyst could realize rapid charge separation. This work can offer a reference for the construction of efficient photocatalysts based on lead halide perovskites. [ABSTRACT FROM AUTHOR]

High crystallinity triangle hexagonal Mn0.45Cu0.05Cd0.5S was obtained by partial Cu ion exchange treatment on colloidal pristine Mn0.5Cd0.5S nanorods. The Mn0.45Cu0.05Cd0.5S nanotriangles exhibited a high hydrogen yield of 147 921 μmol g−1 h−1 under visible light irradiation, about 7.4 times higher than that of pristine Mn0.5Cd0.5S. [ABSTRACT FROM AUTHOR]

Under visible light illumination, the synthesized ZnIn 2 S 4 /NiSe 2 composites achieved up to a hydrogen evolution rate of 3060 µmol/gh−1. The presence of co-catalyst NiSe 2 provided a faster electron transfer channel and greatly suppressed the recombination of photo-generated charges, thereby enhancing the photocatalytic activity. [Display omitted] • A self-assembled microsphere ZnIn 2 S 4 modified by NiSe 2 nanoparticles was successfully prepared by a hot-injection method and successive solvothermal method. • Benefiting from the close contact interface and synergistic effect between ZnIn 2 S 4 and NiSe 2 , the synthesized ZnIn 2 S 4 /NiSe 2 composites achieved up to a photocatalytic hydrogen evolution rate of 3060 µmol/gh−1 without any noble metal loading. • The successful formation of the composite was conducive to the photo-generated electron flow from ZnIn 2 S 4 to NiSe 2 , which improved the charge migration efficiency and retarded the photogenerated carrier recombination. • The ZnIn 2 S 4 /NiSe 2 composite exhibited elevated absorption, redshift absorption edge, and decreased band gap, which were beneficial for light utilization. • The ZnIn 2 S 4 /NiSe 2 composite also exhibited good stability with no obvious decay within 20 h. A well-designed composite based on semiconductor materials can effectively reduce the recombination of photo-generated carriers in photocatalysts by establishing efficient charge transfer channels, which enhances the activity of photocatalytic hydrogen evolution for water splitting. Herein, a ZnIn 2 S 4 /NiSe 2 composite with NiSe 2 nanoparticles tightly anchored on the nanosheets-assembled microspheres ZnIn 2 S 4 was elaborated and successfully synthesized by a hot-injection method followed by a successive solvothermal method. The synergistic effects and close contact interface between ZnIn 2 S 4 and NiSe 2 facilitated charge migration. Under visible light irradiation, the optimal ratio of ZnIn 2 S 4 /NiSe 2 composite achieved an outstanding hydrogen evolution rate of 3060 µmol g−1 h−1 (nearly 12.6 times of unmodified ZnIn 2 S 4) and exhibited superior stability (no apparent decrease within 20 h) in the presence of a sacrificial agent (triethanolamine). Additionally, various characterizations revealed that the recombination of photo-generated carriers was effectively suppressed, visible-light absorption was significantly enhanced, and interface charge transfer was accelerated, thus endowing the ZnIn 2 S 4 /NiSe 2 composite with superior photocatalytic activity. This research provides illuminating insights into using the non-noble metal-based catalyst NiSe 2 as an effective co-catalyst, significantly improving photocatalytic performance and holding great potential in alleviating energy shortages and environmental pollution problems. [ABSTRACT FROM AUTHOR]

[Display omitted] • 2D/2D S-scheme PCN/(0 0 1)-TiO 2 heterojunction was constructed via solvothermal treatment. • Introduced PCN increased light capture capacity and heterojunction with (0 0 1)-TiO 2 effectively separated and transferred photogenerated carriers. • Norfloxacin degradation efficiency reached up to 99% under simulated solar. • The S-scheme reserved the redox ability of PCN and (0 0 1)-TiO 2 nanosheets. Poor visible light response and low separation efficiency of photogenerated carriers restricted the availability of titanium dioxide for antibiotic photodegradation, and the fabrication of two-dimensional/two-dimensional (2D/2D) heterojunction by coupling to a narrower bandgap semiconductor was an effective approach. Herein, a simple solvothermal method was used to grow 2D (0 0 1)-facets-exposed titanium dioxide ((0 0 1)-TiO 2) nanosheets in situ on the surface of 2D polymeric carbon nitride (PCN) nanosheets to obtain PCN/(0 0 1)-TiO 2 heterojunction for the photodegradation of norfloxacin. The synthesized heterojunction composites exhibited superior photodegradation performance, and the norfloxacin degradation rate reached up to 99% under simulated solar for 90 min. The efficient photocatalytic performance was attributed to the reduction of the bandgap and the formation of S-scheme heterojunctions, which enhanced the absorption of visible light and the carrier migration separation efficiency. Futhermore, the hierarchical 2D/2D nanosheet structure and the built-in electric field formed also sped up the charge transfer at the interface. This work presented a new viable solution to the problem of antibiotic contamination. [ABSTRACT FROM AUTHOR]

Different MIL-125-NH 2 (Ti) contents of Zn 0.5 Cd 0.5 S/MIL-125-NH 2 (Ti) (ZCS/MN) composites were synthesized through a simple ultrasonic method and the mechanism of photocatalytic hydrogen production by ZCS/MN composite was proposed. • A simple ultrasonic method to synthesize a series of Zn 0.5 Cd 0.5 S/MIL-125-NH 2 (Ti). • The best H 2 production performance of ZCS/MN40 was better than Pt/Zn 0.5 Cd 0.5 S. • MN could improve the separation efficiency of electrons and holes in ZCS. Hydrogen production by photocatalysis under visible light irradiation is a pivotal means of obtaining hydrogen. In this study, Zn 0.5 Cd 0.5 S was studied to have optimal hydrogen production performance among different zinc-cadmium ratios of Zn x Cd 1-x S, and a series of Zn 0.5 Cd 0.5 S/MIL-125-NH 2 (Ti) composites with different MIL-125-NH 2 (Ti) contents were prepared by simple ultrasonic method. When the percentage of addition of MIL-125-NH 2 (Ti) was 40%, the optimum hydrogen production rate was 92,498 μmol h−1 g−1, and the photocatalytic activity was still stable even after 16 h. The mechanism investigations demonstrated that this excellent activity was owing to enhanced visible light absorption intensity, extremely efficient electron transfer and proper conduction band position. This work provides new insights into highly efficient and stable photocatalyst in hydrogen production from water without noble metal doping. [ABSTRACT FROM AUTHOR]