Acta Chimica Sinica ›› 2022, Vol. 80 ›› Issue (1): 22-28.DOI: 10.6023/A21100455 Previous Articles     Next Articles

Special Issue: 中国科学院青年创新促进会合辑



王旭生b,c,g, 杨胥a,b, 陈春辉b,d, 李红芳a,b, 黄远标a,b,f,*(), 曹荣a,b,e,f   

  1. a福州大学石油化工学院 福州 350108
    b中国科学院福建物质结构研究所结构化学国家重点实验室 福州 350002
    c浙江理工大学材料科学与工程学院 杭州 310018
    d中国科学技术大学化学系 合肥 230026
    e中国福建光电信息科学与技术创新实验室(闽都创新实验室) 福州 350108
    f中国科学院大学 北京 100049
    g暨南大学化学与材料学院 广州 510632
  • 投稿日期:2021-10-13 发布日期:2021-11-29
  • 通讯作者: 黄远标
  • 作者简介:
  • 基金资助:
    项目受国家重点基础研发计划项目(2018YFA0208600); 项目受国家重点基础研发计划项目(2018YFA0704502); 国家自然科学基金(21671188); 国家自然科学基金(21871263); 国家自然科学基金(22071245); 国家自然科学基金(22033008); 国家自然科学基金(22171265); 国家自然科学基金(22001094); 中国科学院青年创新促进会优秀会员项目(Y201850); 中国福建光电信息科学与技术创新实验室(闽都创新实验室)项目(2021ZZ103); 广东省基础与应用基础研究基金(2020A1515110003)

Graphene Quantum Dots Supported on Fe-based Metal-Organic Frameworks for Efficient Photocatalytic CO2 Reduction

Xusheng Wangb,c,g, Xu Yanga,b, Chunhui Chenb,d, Hongfang Lia,b, Yuanbiao Huanga,b,f(), Rong Caoa,b,e,f   

  1. aCollege of Chemical Engineering, Fuzhou University, Fuzhou 350108
    bState Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou 350002
    cSchool of Materials Science and Engineering, Zhejiang Sci-Tech University, Hangzhou 310018
    dDepartment of Chemistry, University of Science and Technology of China, Hefei 230026
    eFujian Science & Technology Innovation Laboratory for Optoelectronic Information of China, Fuzhou 350108
    fUniversity of Chinese Academy of Sciences, Beijing 100049
    gCollege of Chemistry and Materials Science, Jinan University, Guangzhou 510632
  • Received:2021-10-13 Published:2021-11-29
  • Contact: Yuanbiao Huang
  • About author:
    Dedicated to the 10th anniversary of the Youth Innovation Promotion Association, CAS.
  • Supported by:
    National Key Research and Development Program of China(2018YFA0208600); National Key Research and Development Program of China(2018YFA0704502); National Natural Science Foundation of China(21671188); National Natural Science Foundation of China(21871263); National Natural Science Foundation of China(22071245); National Natural Science Foundation of China(22033008); National Natural Science Foundation of China(22171265); National Natural Science Foundation of China(22001094); Youth Innovation Promotion Association, CAS(Y201850); Fujian Science & Technology Innovation Laboratory for Optoelectronic Information of China(2021ZZ103); Guangdong Basic and Applied Basic Research Foundation(2020A1515110003)

Photocatalytic reduction of CO2 to valuable chemicals is an essential but still remains challenging. Metal-organic frameworks (MOFs) featuring high special surface area, large CO2 adsorption uptakes, adjustable structures and function, have become a kind of promising porous materials for photocatalytic CO2 reduction. However, MOFs often suffer from problems like short light harvesting range, rapid recombination of photogenerated carriers, resulting in lower activity. Here, graphene quantum dots (GQD) were supported on the Fe-based nano-sized MOFs, NH2-MIL-88B(Fe), via electrostatic self-assembly strategy. GQDs were prepared by electrolysis of graphite rod in pure water firstly, and then centrifuged to remove the large species. Transmission electron microscope (TEM) reveals that ultrafine GQDs with 3 nm were obtained. Atomic force microscope (AFM) further demonstrates that the thickness of GQDs is around 0.34—1.5 nm (1—4 stacked layers). The MOFs, NH2-MIL-88B(Fe), were synthesized with traditional solvothermal method, with a nano spindle shape of 250 nm×40 nm. The amino groups on MOFs provide strong electrostatic force with the carboxylic groups on GQDs, making the composite very stable and efficient electron transfer. High resolution transmission electron microscope (TEM) reveals that the nano MOFs were surrounded by tiny GQDs firmly. The bandgap of composite was determined by solid ultraviolet visible diffuse reflectance spectroscopy (UV-Vis DRS) and Mott-Schottky measurement, which indicate that it is thermodynamically appropriate for photocatalytic CO2 reduction. Photocurrent experiments further demonstrate the composite is beneficial for the photogenerated electron-hole separation. Thus, the resulting GQD/NH2-MIL-88B(Fe) composite showed much enhanced CO production rate (4 times) compared with the parent NH2-MIL-88B(Fe), reaching 590 μmol/g under 10 h visible light irradiation with triethanolamine (TEOA) as sacrificial agent. The hugely improved photoreduction activity benefits from both the high CO2 adsorption of MOFs and the enhanced separation of photogenerated electrons and holes. This work provides an avenue for preparation of MOFs based materials with high CO2 photoreduction activity.

Key words: metal-organic frameworks, photocatalysis, CO2 reduction, electrostatic self-assembly, graphene quantum dots