催化学报 ›› 2017, Vol. 38 ›› Issue (12): 1936-1955.DOI: 10.1016/S1872-2067(17)62962-0

• 综述 • 上一篇    下一篇

二氧化钛基Z型光催化剂综述

戚克振a,b, 程蓓a, 余家国a,d, Wingkei Hoc   

  1. a 武汉理工大学材料复合新技术国家重点实验室, 湖北武汉 430070, 中国;
    b 沈阳师范大学化学化工学院, 辽宁沈阳 110034, 中国;
    c 香港教育大学科学与环境学系, 香港, 中国;
    d 沙特阿卜杜勒阿齐兹国王大学科学部物理系, 吉达 21589, 沙特阿拉伯
  • 收稿日期:2017-10-18 修回日期:2017-10-31 出版日期:2017-12-18 发布日期:2017-12-29
  • 通讯作者: 余家国, Wingkei Ho
  • 基金资助:

    国家自然科学基金(51602207,21433007,51320105001,21573170);武汉理工大学材料复合新技术国家重点实验室创新基金(2017-ZD-4,2016-KF-17);湖北省自然科学基金(2015CFA001).

A review on TiO2-based Z-scheme photocatalysts

Kezhen Qia,b, Beichenga, Jiaguo Yua,d, Wingkei Hoc   

  1. a State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070, Hubei, China;
    b Institute of Catalysis for Energy and Environment, College of Chemistry and Chemical Engineering, Shenyang Normal University, Shenyang 110034, Liaoning, China;
    c Department of Science and Environmental Studies, the Education University of Hong Kong, Tai Po, N. T. Hong Kong, China;
    d Department of Physics, Faculty of Science, King Abdulaziz University, Jeddah 21589, Saudi Arabia
  • Received:2017-10-18 Revised:2017-10-31 Online:2017-12-18 Published:2017-12-29
  • Supported by:

    This work was supported by the National Natural Science Foundation of China (51602207, 21433007, 51320105001, 21573170), the Self-determined and Innovative Research Funds of SKLWUT (2017-ZD-4, 2016-KF-17), and the Natural Science Foundation of Hubei Province of China (2015CFA001).

摘要:

TiO2具有无毒、耐腐蚀、高稳定和低成本等特点,已被广泛应用于光催化领域.然而,TiO2的禁带较宽,只能吸收仅占太阳光4%的紫外光部分,从而严重限制了TiO2光催化材料对太阳光的有效应用.目前很多方法被用来提高TiO2光催化效率,如金属/非金属掺杂、贵金属负载、异质结构建和与碳材料复合等,这些策略在提高光催化剂的光催化效率中,涉及到如何兼顾太阳光利用和光生空穴和电子氧化还原能力两者之间的平衡.通常,半导体禁带宽度越窄,半导体的光谱响应范围越宽、太阳光利用越多,但光生空穴和电子氧化还原能力越弱.因此,想要提高TiO2的光催化性能,应考虑以下两个方面的平衡:即降低带隙宽度,拓展半导体的光谱响应范围;与之同时使价带电位更正,导带电位更负之间的平衡.然而,这两个点是相互矛盾的,因此很难在单组分光催化剂中同时实现这两点.
然而,Z型光催化剂可以同时满足这两点要求,即:降低半导体的带隙,同时使导带更负,价带更正,因为Z光催化系统利用了两种半导体的优势,其电荷转移机制类似于自然界中绿色植物的光合作用,其中的载流子传输途径包括两步激发,类似于英文字母"Z",Z型光催化剂因此而得名.Z型光催化剂既能保留较高还原能力的光生电子和又能保留较高氧化能力的光生空穴,由于Z型光催化剂特有的优点,在光催化领域的应用越来越广泛.
本文综述了TiO2基Z型光催化剂的最新研究进展,其中包括:Z型光催化机理、应用范围和光催化活性改进方法.Z型光催化剂分为传统液相Z型光催化体系,全固态Z型光催化体系,以及最近几年发展起来的直接Z型光催化体系.它们的主要应用包括:光催化分解水产氢、二氧化碳还原制备太阳燃料、有机污染物光催化降解.论文进一步讨论了提高TiO2基Z型光催化剂性能的方法,包括pH值调控、电子导体选择、助催化剂使用、掺杂改性、组织形貌控制、两种半导体质量比优化等.最后,提出了TiO2基Z型光催化剂今后面临的挑战和发展前景展望.

关键词: 二氧化钛, Z型光催化剂, 光解水, 还原二氧化碳, 污染物降解

Abstract:

TiO2-based Z-scheme photocatalysts have attracted considerable attention because of the low recombination rate of their photogenerated electron-hole pairs and their high photocatalytic efficiency. In this review, the reaction mechanism of Z-scheme photocatalysts, recent research progress in the application of TiO2-based Z-scheme photocatalysts, and improved methods for photocatalytic performance enhancement are explored. Their applications, including water splitting, CO2 reduction, decomposition of volatile organic compounds, and degradation of organic pollutants, are also described. The main factors affecting the photocatalytic performance of TiO2-based Z-scheme photocatalysts, such as pH, conductive medium, cocatalyst, architecture, and mass ratio, are discussed. Concluding remarks are presented, and some suggestions for the future development of TiO2-based Z-scheme photocatalysts are highlighted.

Key words: TiO2, Z-scheme photocatalyst, Water splitting, CO2 reduction, Pollutant degradation