J. Mater. Sci. Technol. ›› 2022, Vol. 121: 220-226.DOI: 10.1016/j.jmst.2022.01.006

• Research Article • Previous Articles     Next Articles

Selective electrocatalytic reduction of CO2 to formate via carbon-shell-encapsulated In2O3 nanoparticles/graphene nanohybrids

Yidu Wanga, Jingnan Dinga, Jun Zhaoa, Jiajun Wanga,c,*(), Xiaopeng Hana, Yida Denga,b,*(), Wenbin Hua,c   

  1. aKey Laboratory of Advanced Ceramics and Machining Technology (Ministry of Education), Tianjin Key Laboratory of Composite and Functional Materials, School of Materials Science and Engineering, Tianjin University, Tianjin 300072, China
    bState Key Laboratory of Marine Resource Utilization in South China Sea, School of Materials Science and Engineering, Hainan University, Haikou 570228, China
    cJoint School of National University of Singapore and Tianjin University, International Campus of Tianjin University, Fuzhou, Binhai New City 350207, China
  • Received:2021-10-12 Revised:2022-01-18 Accepted:2022-01-20 Published:2022-09-10 Online:2022-03-06
  • Contact: Jiajun Wang,Yida Deng
  • About author:yida.deng@tju.edu.cn (Y. Deng).
    *Key Laboratory of Advanced Ceramics and Machin- ing Technology (Ministry of Education), Tianjin Key Laboratory of Composite and Functional Materials, School of Materials Science and Engineering, Tianjin Univer- sity, Tianjin 30 0 072, China. E-mail addresses: wangjiajun90@tju.edu.cn (J. Wang),

Abstract:

Constructing nanohybrids with a synergistic effect using multi-components and specific micro/nanostructures can significantly enhance their electrocatalytic activity. In this work, we fabricated an In2O3⊃NC@GO nanohybrid, in which In2O3 nanoparticles (NPs) were encapsulated by an N-doped carbon (NC) shell and supported on graphene. The multi-components in In2O3⊃NC@GO synergistically optimize the structural and electronic properties of the material. The particle size and dispersion of In2O3 NPs were optimized owing to the separation effect of the amorphous NC shell and graphene support. This separation effect exposes more number of active sites for the electrochemical reaction. Abundant oxygen vacancies exist in In2O3, leading to a stronger ability for the adsorption and activation of CO2. The NC shell inhibits the direct contact between the electrolyte and In2O3, which significantly suppresses competitive H2 evolution. The charge transfer during the electrocatalysis process is also effectively enhanced due to the carbon components. The synergistic effect of multi-components in the In2O3⊃NC@GO sample results in a significantly improved CO2 reduction reaction performance with a high HCOO- Faradic efficiency (FE) of 91.2% and a current density of 40.38 mA cm-2 at -0.8 V obtained using a flow cell. The present work demonstrates that rationally designing nanohybrids with multifunctional components is an effective strategy for optimizing the structural and electrocatalytic properties of materials for energy conversion.

Key words: In2O3, CO2 reduction electrocatalyst, Oxygen vacancies, N-doped carbon, Nanohybrids