Fabrication of hierarchical ZnIn2S4@CNO nanosheets for photocatalytic hydrogen production and CO2 photoreduction

A compendium of all-in-one solar-driven water splitting using ZnIn2S4-based photocatalysts: guiding the path from the past to the limitless future

Photocatalytic water splitting represents a leading approach to harness the abundant solar energy, producing hydrogen as a clean and sustainable energy carrier. Zinc indium sulfide (ZIS) emerges as one of the most captivating candidates attributed to its unique physicochemical and photophysical properties, attracting much interest and holding significant promise in this domain. To develop a highly efficient ZIS-based photocatalytic system for green energy production, it is paramount to comprehensively understand the strengths and limitations of ZIS, particularly within the framework of solar-driven water splitting. This review elucidates the three sequential steps that govern the overall efficiency of ZIS with a sharp focus on the mechanisms and inherent drawbacks associated with each phase, including commonly overlooked aspects such as the jeopardising photocorrosion issue, the neglected oxidative counter surface reaction kinetics in overall water splitting, the sluggish photocarrier dynamics and the undesired side redox reactions. Multifarious material design strategies are discussed to specifically mitigate the formidable limitations and bottleneck issues. This review concludes with the current state of ZIS-based photocatalytic water splitting systems, followed by personal perspectives aimed at elevating the field to practical consideration for future endeavours towards sustainable hydrogen production through solar-driven water splitting.

Constructing a 3D Bi2WO6/ZnIn2S4 direct Z-scheme heterostructure for improved photocatalytic CO2 reduction performance

Developing efficient heterojunction photocatalysts with enhanced charge transfer and reduced recombination rates of photogenerated carriers is crucial for harnessing solar energy in the photocatalytic CO2 reduction into renewable fuels. This study employed electrostatic self-assembly techniques to construct a 3D Bi2WO6/ZnIn2S4 direct Z-scheme heterojunctions. The unique 3D structure provided abundant active sites and facilitated CO2 adsorption. Moreover, the optimized Bi2WO6/ZnIn2S4 composite demonstrated an impressive CH4 yield of 19.54 μmol g-1 under 4 h of simulated sunlight irradiation, which was about 8.73 and 16.30-fold higher than pure ZnIn2S4 and Bi2WO6. The observed enhancements in photocatalytic performance are attributed to forming a direct Z-scheme heterojunction, which effectively promotes charge transport and migration. This research introduces a novel strategy for constructing photocatalysts through the synergistic effect of morphological interface modifications.

Construction of ZnIn2 S4 /CdS/PdS S-Scheme Heterostructure for Efficient Photocatalytic H2 Production

It is facing a tremendous challenge to develop the desirable hybrids for photocatalytic H₂ generation by integrating the advantages of a single semiconductor. Herein, an all-sulfide ZnIn₂ S₄ /CdS/PdS heterojunction is constructed for the first time, where CdS and PdS nanoparticles anchor in the spaces of ZnIn₂ S₄ micro-flowers due to the confinement effects. The morphology engineering can guarantee rapid charge transfer owing to the short carrier migration distances and the luxuriant reactive sites provided by ZnIn₂ S₄ . The S-scheme mechanism between ZnIn₂ S₄ and CdS assisted by PdS cocatalyst is testified by in situ irradiated X-ray photoelectron spectroscopy and electron paramagnetic resonance (EPR), where the electrons and holes move in reverse driven by work function difference and built-in electric field at the interfaces. The optimal ZnIn₂ S₄ /CdS/PdS performs a glaring photocatalytic activity of 191.9 µmol h^-1 (10 mg of catalyst), and the largest AQE (apparent quantum efficiency) can reach a high value of 26.26%. This work may afford progressive tactics to design multifunctional photocatalysts.

Robust visible-light photocatalytic H2 evolution on 2D RGO/Cd0.15Zn0.85In2S4–Ni2P hierarchitectures

Unique 2D ternary hierarchitectures constructed from reduced graphene oxide nanosheets grown with ultrathin Cd0.15Zn0.85In2S4 nanosheets and Ni2P nanoparticles exhibited an outstanding capability for visible-light photocatalytic H2 production.

ZnIn2 S4 -Based Photocatalysts for Energy and Environmental Applications

As a fascinating visible-light-responsive photocatalyst, zinc indium sulfide (ZnIn₂ S₄ ) has attracted extensive interdisciplinary interest and is expected to become a new research hotspot in the near future, due to its nontoxicity, suitable band gap, high physicochemical stability and durability, ease of synthesis, and appealing catalytic activity. This review provides an overview on the recent advances in ZnIn₂ S₄ -based photocatalysts. First, the crystal structures and band structures of ZnIn₂ S₄ are briefly introduced. Then, various modulation strategies of ZnIn₂ S₄ are outlined for better photocatalytic performance, which includes morphology and structure engineering, vacancy engineering, doping engineering, hydrogenation engineering, and the construction of ZnIn₂ S₄ -based composites. Thereafter, the potential applications in the energy and environmental area of ZnIn₂ S₄ -based photocatalysts are summarized. Finally, some personal perspectives about the promises and prospects of this emerging material are provided.

Preparation of a ZnIn2S4–ZnAlOx nanocomposite for photoreduction of CO2 to CO

The ZnIn₂S₄–ZnAlO_x nanocomposite inhibits the recombination of charge carriers and therefore significantly boosts CO₂ photoreduction efficiency.

One-Pot Hydrothermal Synthesis of La-Doped ZnIn2S4 Microspheres with Improved Visible-Light Photocatalytic Performance

Impurity element doping is extensively taken as one of the most efficient strategies to regulate the electronic structure as well as the rate of photogenerated charge separation of photocatalysts. Herein, a one-pot hydrothermal synthesis process was exploited to obtain La-doped ZnIn₂S₄ microspheres, aiming at gaining insight into the role that doping ions played in the improvement of pollutant photodegradation. Systematical characterization means, comprising of X–ray photoelectron spectroscopy (XPS), ultraviolet–visible (UV–vis) diffuse reflection spectroscopy and Raman spectra, combination with high-resolution transmission electron microscopy (HRTEM), were employed to in depth reveal the concomitancy of La ions and ZnIn₂S₄ crystal lattice. The results showed that the La-doped ZnIn₂S₄ samples exhibited a slightly wider and stronger spectral absorption than pristine ZnIn₂S₄; and the specific surface area of doped ZnIn₂S₄ samples was a bit larger. The La-doped ZnIn₂S₄ electrodes showed improved photocurrent response, and the photocurrent density reached a maximum value at La content of 1.5 wt%. As expected, La-doped ZnIn₂S₄ samples exhibited a remarkable enhancement of photocatalytic behaviour toward the photodegradation of tetracycline hydrochloride (TCH) and methyl orange (MO). The prominently enhanced photoactivity of doped ZnIn₂S₄ samples was due to the synergistic effect of the elevated visible-light absorption ability and effective photogenerated charge carriers’ separation.