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This research successfully synthesized SnO2@ZnIn2S4 composites for photocatalytic tap water splitting using a rapid two-step microwave-assisted synthesis method. This study investigated the impact of incorporating a fixed quantity of SnO2 nanoparticles and combining them with various materials to form composites, aiming to enhance photocatalytic hydrogen production. Additionally, different weights of SnO2 nanoparticles were added to the ZnIn2S4 reaction precursor to prepare SnO2@ZnIn2S4 composites for photocatalytic hydrogen production. Notably, the photocatalytic efficiency of SnO2@ZnIn2S4 composites is substantially higher than that of pure SnO2 nanoparticles and ZnIn2S4 nanosheets: 17.9-fold and 6.3-fold, respectively. The enhancement is credited to the successful use of visible light and the facilitation of electron transfer across the heterojunction, leading to the efficient dissociation of electron–hole pairs. Additionally, evaluations of recyclability demonstrated the remarkable longevity of SnO2@ZnIn2S4 composites, maintaining high levels of photocatalytic hydrogen production over eight cycles without significant efficiency loss, indicating their impressive durability. This investigation presents a promising strategy for crafting and producing environmentally sustainable SnO2@ZnIn2S4 composites with prospective implementations in photocatalytic hydrogen generation. [ABSTRACT FROM AUTHOR]

The g-C3N4@ZnIn2S4 heterostructures were successfully synthesized through a combination of thermal annealing and hydrothermal methods. To enhance the photocatalytic hydrogen production performance and explore the interface between charge carriers, heterostructures of g-C3N4@ZnIn2S4 were fabricated using varying weights of g-C3N4 nanostructures under visible light irradiation. Remarkably, the photocatalytic hydrogen production efficiency of g-C3N4@ZnIn2S4 heterostructures with 0.01 g g-C3N4 nanostructures was significantly improved, showing approximately 228.6 and 2.58 times higher than that of g-C3N4 nanostructures and ZnIn2S4 nanostructures, respectively. This enhancement in photocatalytic performance is attributed to the effective utilization of visible light and the efficient separation of photogenerated electron-hole pairs facilitated by the heterojunction structures. Moreover, the reusability test validated the outstanding performance of g-C3N4@ZnIn2S4 heterostructures, as they maintained high photocatalytic hydrogen production even after undergoing eight cycles without any noticeable decrease in efficiency. This study offers a promising strategy for designing and synthesizing an environmentally friendly g-C3N4@ZnIn2S4 heterojunction with potential applications in photocatalytic hydrogen evolution. [ABSTRACT FROM AUTHOR]

In this study, a facile and rapid microwave-assisted synthesis method was used to synthesize In2S3 nanosheets, ZnS nanosheets, and ZnIn2S4 nanosheets with sulfur vacancies. The two-dimensional semiconductor photocatalysts of ZnIn2S4 nanosheets were characterized by XRD, FESEM, BET, TEM, XPS, UV–vis diffuse reflectance, and PL spectroscopy. The ZnIn2S4 with sulfur vacancies exhibited an evident energy bandgap value of 2.82 eV, as determined by UV–visible diffuse reflectance spectroscopy, and its energy band diagram was obtained through the combination of XPS and energy bandgap values. ZnIn2S4 nanosheets exhibited about 33.3 and 16.6 times higher photocatalytic hydrogen production than In2S3 nanosheets and ZnS nanosheets, respectively, under visible-light irradiation. Various factors, including materials, sacrificial reagents, and pH values, were used to evaluate the influence of ZnIn2S4 nanosheets on photocatalytic hydrogen production. In addition, the ZnIn2S4 nanosheets revealed the highest photocatalytic hydrogen production from seawater, which was about 209.4 and 106.7 times higher than that of In2S3 nanosheets and ZnS nanosheets, respectively. The presence of sulfur vacancies in ZnIn2S4 nanosheets offers promising opportunities for developing highly efficient and stable photocatalysts for photocatalytic hydrogen production from seawater under visible-light irradiation. [ABSTRACT FROM AUTHOR]

We have demonstrated a two-step wet chemical approach for synthesizing ternary Ag/Ag2S/CdS heterostructures for efficient photocatalytic hydrogen evolution. The CdS precursor concentrations and reaction temperatures are crucial in determining the efficiency of photocatalytic water splitting under visible light excitation. In addition, the effect of operational parameters (such as the pH value, sacrificial reagents, reusability, water bases, and light sources) on the photocatalytic hydrogen production of Ag/Ag2S/CdS heterostructures was investigated. As a result, Ag/Ag2S/CdS heterostructures exhibited a 3.1-fold enhancement in photocatalytic activities compared to bare CdS nanoparticles. Furthermore, the combination of Ag, Ag2S, and CdS can significantly enhance light absorption and facilitate the separation and transport of photogenerated carriers through the surface plasma resonance (SPR) effect. Furthermore, the Ag/Ag2S/CdS heterostructures in seawater exhibited a pH value approximately 2.09 times higher than in de-ionized water without an adjusted pH value under visible light excitation. The ternary Ag/Ag2S/CdS heterostructures provide new potential for designing efficient and stable photocatalysts for photocatalytic hydrogen evolution. [ABSTRACT FROM AUTHOR]

In the present work, we described the synthesis and characterization of the ternary Cu2O/CuS/ZnS nanocomposite using a facile two-step wet chemical method for blue LED-light-induced photocatalytic hydrogen production. The concentrations of the ZnS precursor and reaction time were essential in controlling the photocatalytic hydrogen production efficiency of the Cu2O/CuS/ZnS nanocomposite under blue LED light irradiation. The optimized Cu2O/CuS/ZnS nanocomposite exhibited a maximum photocatalytic hydrogen evolution rate of 1109 µmolh−1g−1, which was remarkably higher than Cu2O nanostructures. Through the cycle stability it can be observed that the hydrogen production rate of the Cu2O/CuS/ZnS nanocomposite decreased after 4 cycles (1 cycle = 3 h), but it remained at 82.2% of the initial performance under blue LED light irradiation. These reasons are mainly attributed to the introduction of CuS and ZnS to construct a rationally coupled reaction system, which enables the synergistic utilization of photogenerated carriers and the increased absorption of visible light for boosting blue LED-light-driven photocatalytic hydrogen evolution. [ABSTRACT FROM AUTHOR]

• Multistep processes can successfully synthesize the TiO 2 /NiS/Pt nanofiber (NF). • The TiO 2 /NiS/Pt NF exhibited enhanced photocatalytic activity for H 2 evolution. • The HER over the TiO 2 /NiS/Pt NF has 292 times increase over pure TiO 2 NF. • TiO 2 /NiS/Pt NF can lead to carriers' higher separation and transfer efficiency. • TiO 2 /NiS/Pt NF can provide practical application in seawater splitting. The porous TiO 2 nanofiber has been synthesized via facile electrospinning and thermal annealing. Furthermore, the intermediate layer of NiS and Pt nanoparticles can be sequentially deposited on the porous TiO 2 nanofiber to form hierarchical core-shell TiO 2 /NiS/Pt nanofiber through wet-chemical and self-assembly processes. Compared with the TiO 2 (16 µmolh−1g−1 L−1) nanofiber and TiO 2 /NiS nanofiber (54 µmolh−1g−1 L−1), TiO 2 /NiS/Pt nanofiber (4411 µmolh−1g−1 L−1) revealed remarkably photocatalytic activity for hydrogen evolution from water under visible light excitation. The significant enhancement in photocatalytic activity over the TiO 2 /NiS/Pt nanofiber could be attributed to enhanced visible light absorption and the separation of photogenerated electrons and holes. Furthermore, reusability experiments prove that TiO 2 /NiS/Pt nanofiber exhibits excellent stability for the long-term photocatalytic process. In addition, TiO 2 /NiS/Pt nanofiber can also use photocatalytic hydrogen production under different water bases. Therefore, this study provides a promising strategy to develop a novel heterostructure photocatalyst for highly efficient energy conversion. [Display omitted] [ABSTRACT FROM AUTHOR]

Lowering the cost and increasing the efficiency of photocatalysts for hydrogen (H 2) evolution remain challenging, especially with eco-friendly materials. With these goals in mind, in this study we adopted tungsten disulfide (WS 2) nanosheets, a nonmetallic surface plasmon resonance (SPR) material covering P25 TiO 2 , for plasmon-induced resonance energy transfer (PIRET) to improve the photocarrier response of H 2 evolution. Under simulated solar light irradiation, the optimized 2.4W heterostructure provided a durable and outstanding H 2 evolution rate (321 μmol g−1 h−1) that was approximately 55.3 times higher than that of TiO 2. Raman spectra revealed the presence of dipole–dipole interactions within the WS 2 –TiO 2 heterostructure, while UV–Vis optical absorption spectra indicated that the WS 2 absorption range overlaid the band gap of TiO 2. Under irradiation with light, the SPR of the WS 2 nanosheets underwent near-field dipole-dipole coupling with the excitons of TiO 2 to increase the number of excitons and inhibit charge recombination. This study suggests the possibility of using nonmetallic SPR materials for efficient solar energy conversion. • Hybrid photocatalysts of WS 2 –TiO 2 were prepared through a facile process. • Plasmon-induced resonance energy transfer of WS 2 –TiO 2 catalysts improves efficiency of photocatalytic hydrogen evolution. • The 2.4 wt% WS 2 –TiO 2 (2.4W) exhibited a photocatalytic hydrogen evolution rate 55.3 times higher than that of pristine TiO 2. [ABSTRACT FROM AUTHOR]

A MoS 2 /graphene hybrid (MSG) is synthesized by microwave hydrothermal method. Both of the charge transfer resistance and the photocurrent are tuned in graphene modified MoS 2 by enhancing photocatalytic nature, where the charge transfer resistance significantly decreases from 36,000 Ω–8.49 Ω and the photocurrent promotes from 0.29 mA cm−2 to 16.47 mA cm−2. In this article, the result reveals that the appropriate modification of graphene can reach the maximum yield of hydrogen gas. In addition, the appropriate conditions, such as the concentration of 0.32 M formic acid and the MoS 2 photocatalyst with 0.8 wt% graphene (MSG 0.8) dose of 0.013 g L−1, can complete the outstanding photocatalytic hydrogen evolution, where the hydrogen evolution using MSG 0.8 composite photocatalyst has the maximum yield of 667.2 μmol h−1 g−1. Image 1 • Graphene modified MoS 2 could tune the charge transfer resistance and the photo current as well. • Formic acid acts as electron donor to capture photogenerated holes to improve hydrogen production. • MSG 0.8 has the maximum hydrogen evolution rate of 667.2 μmol h−1 g−1. [ABSTRACT FROM AUTHOR]