J. Mater. Sci. Technol. ›› 2025, Vol. 204: 47-59.DOI: 10.1016/j.jmst.2024.03.025

• Research Article • Previous Articles     Next Articles

Tailoring the morphology and charge transfer pathways of ultrathin Cd0.8Zn0.2S nanosheets via ionic liquid-modified Ti3C2 MXenes towards remarkable photocatalytic hydrogen evolution

Qianqian Hua,e,*, Haiyan Yina,b, Yifan Liua,b, Abdusalam Ableza,b, Zhuangzhuang Wanga,b, Yue Zhanc, Chengfeng Dud, Xiaoying Huanga,e   

  1. aState Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou 350002, China;
    bCollege of Chemistry, Fuzhou University, Fuzhou 350116, China;
    cCollege of Chemistry and Materials Science, Fujian Normal University, Fuzhou 350007, China;
    dState Key Laboratory of Solidification Processing, Center of Advanced Lubrication and Seal Materials, School of Materials Science and Engineering, Northwestern Polytechnical University, Xi'an 710072, China;
    eUniversity of the Chinese Academy of Sciences, Beijing 100039, China
  • Received:2024-02-05 Revised:2024-03-08 Accepted:2024-03-15 Published:2025-01-01 Online:2024-04-13
  • Contact: *E-mail address: huqianqian@fjirsm.ac.cn (Q. Hu).

Abstract: Small-sized CdxZn1-xS solid solution nanomaterial is an important candidate for efficient photocatalytic hydrogen evolution (PHE), but it still suffers from easy agglomeration, severe photo corrosion, and fast photogenerated electron-hole recombination. To tackle these issues, herein, we propose a new strategy to modify CdxZn1-xS nanoreactors by the simultaneous utilization of ionic-liquid)-assisted morphology engineering and MXene-incorporating method. That is, we designed and synthesized a novel hierarchical Cd0.8Zn0.2S/Ti3C2 Schottky junction composite through the in-situ deposition of ultrathin Cd0.8Zn0.2S nanosheets on unique IL-modified Ti3C2 MXenes by a one-pot solvothermal method for efficiently PHE. The unique construction strategy tailors the thickness of ultrathin Cd0.8Zn0.2S nanosheets and prevents them from stacking and agglomeration, and especially, optimizes their charge transfer pathways during the photocatalytic process. Compared with pristine Cd0.8Zn0.2S nanosheets, Cd0.8Zn0.2S/Ti3C2 has abundant photogenerated electrons available on the Ti3C2 surface for proton reduction reaction, owing to the absence of deep-trapped electrons, suppression of electron-hole recombination in Cd0.8Zn0.2S and high-efficiency charge separation at the Cd0.8Zn0.2S/Ti3C2 Schottky junction interface. Moreover, the hydrophilicity, electrical conductivity, visible-light absorption capacity, and surficial hydrogen desorption of Cd0.8Zn0.2S/Ti3C2 heterostructure are significantly improved. As a result, the heterostructure exhibits outstanding photocatalytic stability and super high apparent quantum efficiency, being rendered as one of the best noble-metal-free Cd-Zn-S-based photocatalysts. This work illustrates the mechanisms of morphology control and heterojunction construction in controlling the catalytic behavior of photocatalysts and highlights the great potential of the IL-assisted route in the synthesis of high-performance MXene-based heterostructures for photocatalytic hydrogen evolution.

Key words: Ionic liquid, Ultrathin Cd0.8Zn0.2S nanosheets, MXene, Schottky junction, Photoexcited charge separation, Photocatalytic H2 evolution