Ultrathin Defective Nanosheet Subunit ZnIn₂S₄ Hollow Nanoflowers for Efficient Photocatalytic Hydrogen Evolution

Abstract

Constructing hierarchical and ultrathin‐structured metal sulfides is beneficial for achieving high‐efficiency hydrogen evolution catalysts. Herein, ZnIn2S4 (ZIS) hollow nanoflowers (HNFs) composed of ultrathin nanosheets are creatively synthesized via a facile trisodium citrate‐mediated and stirring‐assisted solvothermal method. Experimental results reveal that the synergy effect of ethanol, trisodium citrate, and continuous stirring during solvothermal synthesis process play a significant role in optimizing microstructure as well as physicochemical properties of as‐prepared ZIS samples. Importantly, the fabricated ZIS HNFs with the thinnest nanosheets (2.28 nm) manifest the highest average photocatalytic hydrogen generation rate of 301.5 μmol h−1, which is 2.3 times higher than that of the pristine ZIS microspheres composed of nanoparticles with Pt as the cocatalyst and triethanolamine (TEOA) as the sacrificial agent and outperforms most reported ZnIn2S4‐based materials under similar testing conditions. Moreover, the optimized sample also shows a hydrogen generation rate of 0.53 μmol h−1.in pure water without any cocatalyst. This controllable agitation of the reaction mixture during the hydro/solvothermal synthesis process offers an eco‐friendly and scalable approach for tuning the microstructure of nanomaterials with enhanced performance for various applications.

The Positive Versus Negative Effects of Defect Engineering for Solar Water Splitting: A Review

“…Specific morphologies can also be obtained by leveraging the coordination effect of solvents. In a study conducted by Ding et al, [85] a structure-directing agent, trisodium citrate, was added to a solvent mixture of ethanol and water to promote the formation of hollow ZnIn 2 S 4 structures with introduced S vacancies. The authors detected the presence of coordination interactions between the citrate groups and metal ions via Fouriertransform infrared spectroscopy analysis.…”

Tailoring the d-band center enables La doped ZnIn2S4 to be active for boosting photocatalytic activation of oxygen and degradation of antibiotics in wastewater

“…19 In particular, ZnIn 2 S 4 (ZIS) is a promising candidate for O 2 photoactivation due to its tunable band gap (2.06-2.85 eV), exceptional chemical stability, and low toxicity. [20][21][22] Previous studies have shown that the initial step in O 2 photoactivation involves the adsorption of O 2 onto ZIS, followed by electron transfer from ZIS to O 2 , resulting in the generation of ROS. 23 However, the capability of ZIS to activate O 2 and transfer surface charge is limited.…”