Acta Phys. -Chim. Sin. ›› 2017, Vol. 33 ›› Issue (9): 1884-1890.doi: 10.3866/PKU.WHXB201705084

• ARTICLE • Previous Articles     Next Articles

Visible-Light Photocatalytic Reduction of CO2 by CoTe Prepared via a Template-Free Hydrothermal Method

Liang ZHOU1,2,Xue-Hua ZHANG2,Lin LIN2,3,Pan LI2,3,Kun-Juan SHAO2,3,Chun-Zhong LI1,*(),Tao HE2,3,*()   

  1. 1 School of Materials Science and Engineering, East China University of Science and Technology, Shanghai 200237, P. R. China
    2 CAS Key Laboratory of Nanosystem and Hierarchical Fabrication, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing 100190, P. R. China
    3 University of Chinese Academy of Sciences, Beijing 100049, P. R. China
  • Received:2017-04-05 Published:2017-07-05
  • Contact: Chun-Zhong LI,Tao HE E-mail:czli@ecust.edu.cn;het@nanoctr.cn
  • Supported by:
    the National Special Project of International Cooperation in Science and Technology, Ministry of Science and Technology of China(2015DFG62610);National Natural Science Foundation of China(21673052)

Abstract:

A CoTenanocatalyst has been successfully synthesized via a template-free hydrothermal method. Inorganic reactants were used so as not to introduce carbon residue contamination. The as-prepared sample was characterized by many techniques, including X-ray diffraction, scanning electron microscopy, ultraviolet-visible light absorption spectroscopy, and X-ray photoelectron spectroscopy. The obtained sample was found to be sponge-like CoTe with a hexagonal structure, which exhibited visible-light (λ > 420 nm) photocatalytic activity. Photoreduction of CO2 over CoTe is believed to have undergone via the carbene pathway. The CO2 was photocatalytically reduced into CH4 with a low yield when N, N-dimethylacetamide (DMA) or water was used as the solvent. When the sacrificial agent triethanolamine (TEOA) was introduced into the photocatalytic system, however, the product was CO instead. These results indicated that both the solvent and sacrificial agent can influence the photoreduction of CO2 over the CoTenanocatalyst. Usually, the solubility of CO2 in an organic solvent such as DMA is higher than that in the pure water, leading to a larger product yield. The presence of TEOA may change the adsorption characteristics of CO onto the surface of the CoTe catalyst, as well as enhance the separation efficiency of photogenerated charge carriers, resulting in a change in the activity and selectivity of CO2 photoreduction.

Key words: CoTe, CO2, Photocatalytic reduction, Organic solvent, Sacrificial agent

MSC2000: 

  • O643