物理化学学报 >> 2021, Vol. 37 >> Issue (6): 2009030.doi: 10.3866/PKU.WHXB202009030

所属专题: 先进光催化剂设计与制备

综述 上一篇    下一篇

g-C3N4表面改性及其光催化制H2与CO2还原研究进展

李云锋1,*(), 张敏1, 周亮1, 杨思佳1, 武占省1,*(), 马玉花2,*()   

  1. 1 西安工程大学环境与化学工程学院,西安 71004
    2 新疆师范大学化学化工学院,乌鲁木齐 830054
  • 收稿日期:2020-09-07 录用日期:2020-10-08 发布日期:2020-10-19
  • 通讯作者: 李云锋,武占省,马玉花 E-mail:liyf377@nenu.edu.cn;wuzhans@126.com;15199141253@163.com
  • 作者简介:Yunfeng Li received his Ph.D. from Northeast Normal University in 2018. He then joined College of Environmental and Chemical Engineering in Xi'an Polytechnic University as Assistant Professor. His research interests focus on environment and energy photocatalysis
    Zhansheng Wu, received his Ph.D. from Beijing Institute of Technology in 2011. He then joined School of Environmental and Chemical Engineering in Xi'an Polytechnic University as Professor. His research interests focus on environmental chemical engineering
    Yuhua Ma obtained her Ph.D. degree from Xinjiang University in 2017. She then became a lecturer at Xinjiang Normal University. Her main research background lies in the area of nanostructured semiconductor photocatalyst for energy and environmental applications
  • 基金资助:
    国家自然科学基金(22008185);国家自然科学基金(52063028);陕西省教育厅科研项目(19JK0376);陕西省自然科学基础研究项目(2019JQ-841);国家级大学生创新创业训练计划项目(S202010709004)

Recent Advances in Surface-Modified g-C3N4-Based Photocatalysts for H2 Production and CO2 Reduction

Yunfeng Li1,*(), Min Zhang1, Liang Zhou1, Sijia Yang1, Zhansheng Wu1,*(), Ma Yuhua2,*()   

  1. 1 College of Environmental and Chemical Engineering, Xi'an Polytechnic University, Xi'an 710000, China
    2 College of Chemistry and Chemical Engineering, Xinjiang Normal University, Urumqi 830054, China
  • Received:2020-09-07 Accepted:2020-10-08 Published:2020-10-19
  • Contact: Yunfeng Li,Zhansheng Wu,Ma Yuhua E-mail:liyf377@nenu.edu.cn;wuzhans@126.com;15199141253@163.com
  • About author:Emails: 15199141253@163.com (Y.M)
    Emails: wuzhans@126.com (Z.W)
    Emails: liyf377@nenu.edu.cn (Y.L), Tel.: +86-13134451412 (Y.L)
  • Supported by:
    the National Natural Science Foundation of China(22008185);the National Natural Science Foundation of China(52063028);Scientific Research Program Funded by Shaanxi Provincial Education Department(19JK0376);Natural Science Basic Research Program of Shaanxi(2019JQ-841);National Training Program of Innovation and Entrepreneurship for Undergraduates(S202010709004)

摘要:

石墨相氮化碳(g-C3N4)作为一种不含金属的有机高分子材料,因独特的能带结构、易于制备以及成本低廉而备受关注。但一些瓶颈问题仍然制约着其光催化活性。截至目前,人们已经尝试了许多方法来优化g-C3N4的光电性能,例如:元素掺杂、官能团改性以及构筑异质结等,而这些改性策略均与g-C3N4的表面行为密切相关。所以,g-C3N4的表面行为对其光催化性能起着关键作用。因此,本文对典型表面改性方法(表面功能化和构建异质结)制备的g-C3N4基光催化剂进行了全面综述,阐述了其光激发和响应机制,详细介绍了其可见光照射下光生载流子的转移路线和表面催化反应。此外,本文总结了表面改性g-C3N4基光催化剂在光催化制氢与CO2还原方面的潜在应用。最后,根据已有研究,我们提出了今后有待进一步探索与解决的几方面问题。

关键词: 光催化, 制氢, CO2还原, 表面改性, 异质结

Abstract:

Solar energy is the largest renewable energy source in the world and the primary energy source of wind energy, tidal energy, biomass energy, and fossil fuel. Photocatalysis technology is a sunlight-driven chemical reaction process on the surface of photocatalysts that can generate H2 from water, decompose organic contaminants, and reduce CO2 into organic fuels. As a metal-free polymeric material, graphite-like carbon nitride (g-C3N4) has attracted significant attention because of its special band structure, easy fabrication, and low costs. However, some bottlenecks still limit its photocatalytic performance. To date, numerous strategies have been employed to optimize the photoelectric properties of g-C3N4, such as element doping, functional group modification, and construction of heterojunctions. Remarkably, these modification strategies are strongly associated with the surface behavior of g-C3N4, which plays a key role in efficient photocatalytic performance. In this review, we endeavor to provide a comprehensive summary of g-C3N4-based photocatalysts prepared through typical surface modification strategies (surface functionalization and construction of heterojunctions) and elaborate their special light-excitation and response mechanism, photo-generated carrier transfer route, and surface catalytic reaction in detail under visible-light irradiation. Moreover, the potential applications of the surface-modified g-C3N4-based photocatalysts for photocatalytic H2 generation and reduction of CO2 into fuels are summarized. Finally, based on the current research, the key challenges that should be further studied and overcome are highlighted. The following are the objectives that future studies need to focus on: (1) Although considerable effort has been made to develop a surface modification strategy for g-C3N4, its photocatalytic efficiency is still too low to meet industrial application standards. The currently obtained solar-to‑hydrogen (STH) conversion efficiency of g-C3N4 for H2 generation is approximately 2%, which is considerably lower than the commercial standards of 10%. Thus, the regulation of the surface/textural properties and electronic band structure of g-C3N4 should be further elucidated to improve its photocatalytic performance. (2) Significant challenges remain in the design and construction of g-C3N4-based S-scheme heterojunction photocatalysts by facile, low-cost, and reliable methods. To overcome the limitations of conventional heterojunctions thoroughly, a promising S-scheme heterojunction photocatalytic system was recently reported. The study further clarifies the charge transfer route and mechanism during the catalytic process. Thus, the rational design and synthesis of g-C3N4-based S-scheme heterojunctions will attract extensive scientific interest in the next few years in this field. (3) First-principle calculation is an effective strategy to study the optical, electrical, magnetic, and other physicochemical properties of surface strategy modified g-C3N4, providing important information to reveal the charge transfer path and intrinsic catalytic mechanism. As a result, density functional theory (DFT) computation will be paid increasing attention and widely applied in surface-modified g-C3N4-based photocatalysts.

Key words: Photocatalysis, H2 generation, CO2 reduction, Surface modification, Heterojunction