Acta Chimica Sinica ›› 2021, Vol. 79 ›› Issue (7): 932-940.DOI: 10.6023/A21030118 Previous Articles     Next Articles



王瑞兆a,b, 邹云杰a,b, 洪晟a,b, 徐铭楷a,b, 凌岚a,b,*()   

  1. a 同济大学 污染控制与资源化研究国家重点实验室 上海 200092
    b 福州大学 能源与环境光催化国家重点实验室 福州 350116
  • 投稿日期:2021-03-29 发布日期:2021-05-31
  • 通讯作者: 凌岚
  • 基金资助:
    国家自然科学基金优秀青年基金(21822607); 能源与环境光催化国家重点实验室开放课题(SKLPEE-KF201701)

High-performance Pt0.01Fe0.05-g-C3N4 Catalyst for Photothermal Catalytic CO2 Reduction

Ruizhao Wanga,b, Yunjie Zoua,b, Sheng Honga,b, Mingkai Xua,b, Lan Linga,b()   

  1. a State Key Laboratory of Pollution Control and Resource Reuse, Tongji University, Shanghai 200092, China
    b State Key Laboratory of Photocatalysis on Energy and Environment, Fuzhou University, Fuzhou 350116, China
  • Received:2021-03-29 Published:2021-05-31
  • Contact: Lan Ling
  • Supported by:
    National Natural Science Foundation of China(21822607); State Key Laboratory of Photocatalysis on Energy and Environment(SKLPEE-KF201701)

Converting CO2 into value-added compounds via photothermal catalysis is a promising strategy to reduce CO2 emission and might be a sustainable alternative to traditional fossil fuels. Here, we report nano-structured a Pt0.01Fe0.05-g-C3N4 hybrid catalyst synthesized via hydrothermal-method and further reduced under reaction condition for the reverse water gas shift (RWGS) reaction. Taking advantage of the photo-thermal effect caused by the near-infrared (NIR) and visible light responsive, the hybrid catalyst produces a remarkable activity (7.36 mmol•h-1•gcat-1) for CO2 reduction with CO selectivity (97%) under 300 W Xe lamp irradiation and CO2/H2 (V/V, 1/1) feed gas. The apparent activation energy of reaction decreases from 238.59 kJ/mol to 48.88 kJ/mol calculated by Arrhenius formula. In order to comprehend the good catalytic activity of Pt0.01Fe0.05-g-C3N4in the RWGS reaction, the catalyst is characterized with powder X-ray diffraction (XRD), spherical-aberration-corrected scanning transmission electron microscopy (Cs-S/TEM) integrated with X-ray energy dispersive spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), UV-vis-NIR diffuse reflectance spectroscopy (DRS),etc. for investigating the structural information, surface state, optical properties and so on. Results show that the presence of FeO x and Pt exhibits strong absorption in a wide range from UV to NIR regions. Low photoluminescence (PL) intensity at about 460 nm shows the suppressed photogenerated carrier recombination process of Pt0.01Fe0.05-g-C3N4 due to the heterojunction between FeO x and g-C3N4. Operando diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) under different reaction conditions is employed to investigate surface species and their evolution during the conversion of CO2 into CO and a broad IR absorption is observed due to hydrogen spillover from Pt to Fe3O4. Therefore, we propose a possible mechanism of photothermal catalytic CO2 reduction, involving separate activation of CO2 and H2 over Fe and Pt acitve sites. Our work present a high-performance Pt0.01Fe0.05-g-C3N4 catalyst for RWGS reaction and open a new vista of the design, synthesis and mechanism research of photothermal catalytic CO2 conversion in the future.

Key words: g-C3N4, photothermal catalysis, CO2 reduction reaction, operando diffuse reflectance infrared Fourier transform spectroscopy