催化学报 ›› 2022, Vol. 43 ›› Issue (10): 2720-2731.DOI: 10.1016/S1872-2067(22)64133-0

• 论文 • 上一篇    下一篇

2D/2D/2D三明治结构ZnIn2S4/g-C3N4/Ti3C2 Mxene S型异质结-肖特基结双通道电荷转移路径促进的光催化析氢

王乐乐a,c, 杨涛a, 彭李杰a, 张琪琪c, 佘希林b,#(), 唐华b, 刘芹芹a,*()   

  1. a江苏大学材料科学与工程学院, 江苏镇江 212013
    b青岛大学环境科学与工程学院, 山东青岛 266071
    c福州大学化学学院能源与环境光催化国家重点实验室, 福建福州 350108
  • 收稿日期:2022-03-17 接受日期:2022-04-27 出版日期:2022-10-18 发布日期:2022-09-30
  • 通讯作者: 佘希林,刘芹芹
  • 基金资助:
    国家自然科学基金(21975110);国家自然科学基金(21972058);国家自然科学基金(22102064);泰山学者青年专家计划;福州大学能源与环境光催化国家重点实验室开放课题(SKLPEE-KF202102)

Dual transfer channels of photo-carriers in 2D/2D/2D sandwich-like ZnIn2S4/g-C3N4/Ti3C2 MXene S-scheme/Schottky heterojunction for boosting photocatalytic H2 evolution

Lele Wanga,c, Tao Yanga, Lijie Penga, Qiqi Zhangc, Xilin Sheb,#(), Hua Tangb, Qinqin Liua,*()   

  1. aSchool of Materials Science & Engineering, Jiangsu University, Zhenjiang 212013, Jiangsu, China
    bSchool of Environmental Science and Engineering, Qingdao University, Qingdao, 266071, Shandong, China
    cState Key Laboratory of Photocatalysis on Energy and Environment, College of Chemistry, Fuzhou University, Fuzhou 350108, Fujian, China
  • Received:2022-03-17 Accepted:2022-04-27 Online:2022-10-18 Published:2022-09-30
  • Contact: Xilin She, Qinqin Liu
  • Supported by:
    National Natural Science Foundation of China(21975110);National Natural Science Foundation of China(21972058);National Natural Science Foundation of China(22102064);Taishan Youth Scholar Program of Shandong Province;Open Project Program of the State Key Laboratory of Photocatalysis on Energy and Environment,Fuzhou University(SKLPEE-KF202102)

摘要:

氢的能量密度高, 易于储存和运输, 因此, 人工制氢已成为解决能源危机和环境污染问题的有效途径之一, 开发可持续、温和、高效的制氢方法受到了广泛关注. 在众多的制氢方法中, 光催化水分解制氢已发展成为一种理想的制氢途径. 然而受制于光催化剂的光响应范围窄、电荷分离效率低和活性位点少等问题, 目前的光催化分解水制氢效率仍然处于一个较低水平, 严重限制了其实际应用, 因此, 探究高效的光催化分解水材料的新体系与新机制成为解决上述问题的核心任务.

ZnIn2S4是一种典型的具有可见光活性和化学稳定性的半导体, 但由于光生电子的快速复合和严重的光腐蚀限制了其在光催化中的实际应用. 本文采用界面工程, 将ZnIn2S4, g-C3N4和Ti3C2 MXene材料耦合, 设计构建了具有双异质结的2D/2D/2D三明治结构ZnIn2S4/g-C3N4/Ti3C2 MXene复合材料; 通过构筑多界面双电子通道光催化体系, 提高催化体系的电荷分离效率、活性位点的暴露数量以及催化性能. 实验表明, 合成的2D/2D/2D夹层三明治状ZnIn2S4/g-C3N4/Ti3C2 MXene复合材料中, ZnIn2S4与g-C3N4间构成了S型异质结, g-C3N4与类金属性Ti3C2之间构成肖特基结, 显著提高了光生载流子的分离效率, 保留了体系的强氧化还原能力, 并抑制了ZnIn2S4的光腐蚀. 理论计算验证了三元复合物模型的稳定存在, 功函数的计算结果证明了双异质结的形成. 最优比例时, 三元异质结在无助催化剂的情况下产氢速率达到2452.1 μmol∙g‒1∙h‒1 (420 nm处的表观量子效率达到11.9%), 分别是纯ZnIn2S4和石墨相g-C3N4的3倍和200倍. 此外, 经过多次循环反应, 催化剂仍表现出良好的催化活性和稳定性.

2D/2D/2D夹层三明治状ZnIn2S4/g-C3N4/Ti3C2 MXene复合材料具有较高的可见光响应能力和较好的光催化产氢性能归因于以下协同因素: (1)具有2D/2D/2D界面的三明治状异质结构促进了光催化反应中的电子转移和电荷分离; (2)在复合材料中同时形成S型异质结和肖特基异质结, 提供了更强的光氧化还原能力, 双电荷转移通道加速了载流子的迁移. 本研究为构建高效光催化析氢体系提供了可行思路.

关键词: 双电荷转移通道, 光催化产氢, ZnIn2S4/g-C3N4/Ti3C2 MXene复合材料, S型异质结, 肖特基结

Abstract:

Construction of multi-channels of photo-carrier migration in photocatalysts is favor to boost conversion efficiency of solar energy by promoting the charge separation and transfer. Herein, a ternary ZnIn2S4/g-C3N4/Ti3C2 MXene hybrid composed of S-scheme junction integrated Schottky-junction was fabricated using a simple hydrothermal approach. All the components (g-C3N4, ZnIn2S4 and Ti3C2 MXene) demonstrated two-dimensional (2D) nanosheets structure, leading to the formation of a 2D/2D/2D sandwich-like structure with intimate large interface for carrier migration. Furthermore, the photogenerated carriers on the g-C3N4 possessed dual transfer channels, including one route in S-scheme transfer mode between the g-C3N4 and ZnIn2S4 and the other route in Schottky-junction between g-C3N4 and Ti3C2 MXene. Consequently, a highly efficient carrier separation and transport was realized in the ZnIn2S4/g-C3N4/Ti3C2 MXene heterojunction. This ternary sample exhibited wide light response from 200 to 1400 nm and excellent photocatalytic H2 evolution of 2452.1 μmol∙g-1∙h-1, which was 200, 3, 1.5 and 1.6 times of g-C3N4, ZnIn2S4, ZnIn2S4/Ti3C2 MXene and g-C3N4/ZnIn2S4 binary composites. This work offers a paradigm for the rational construction of multi-electron pathways to regulate the charge separation and migration via the introduction of dual-junctions in catalytic system.

Key words: Dual carrier transfer channel, Photocatalytic H2 evolution, ZnIn2S4/g-C3N4/Ti3C2 MXene composite, S-scheme, Schottky-junction