Regulating the thickness of the carbon coating layer in iron/carbon heterostructures to enhance the catalytic performance for oxygen evolution reaction

Taotao Gao; Shumin Yu; Yutao Chen; Xiaoqin Li; Xiangmin Tang; Shuaiwei Wu; Bin He; Hai Lan; Shulong Li; Qu Yue; Dan Xiao

doi:10.1016/j.jcis.2023.03.067

Regulating the thickness of the carbon coating layer in iron/carbon heterostructures to enhance the catalytic performance for oxygen evolution reaction

J Colloid Interface Sci. 2023 Jul 15:642:120-128. doi: 10.1016/j.jcis.2023.03.067. Epub 2023 Mar 15.

Authors

Taotao Gao¹, Shumin Yu², Yutao Chen², Xiaoqin Li¹, Xiangmin Tang², Shuaiwei Wu², Bin He², Hai Lan³, Shulong Li⁴, Qu Yue⁵, Dan Xiao⁶

Affiliations

¹ Institute for Advanced Study, Chengdu University, Chengdu 610106, PR China.
² School of Mechanical Engineering, Chengdu University, Chengdu 610106, PR China.
³ College of Materials Science and Engineering, Chongqing Jiaotong University, Chongqing 400074, PR China.
⁴ Institute for Advanced Study, Chengdu University, Chengdu 610106, PR China. Electronic address: lishulong@cdu.edu.cn.
⁵ Institute for Advanced Study, Chengdu University, Chengdu 610106, PR China. Electronic address: yuequ@cdu.edu.cn.
⁶ Institute for Advanced Study, Chengdu University, Chengdu 610106, PR China; College of Chemical Engineering, Sichuan University, Chengdu 610064, PR China. Electronic address: xiaodan@scu.edu.cn.

PMID: 37001451
DOI: 10.1016/j.jcis.2023.03.067

Abstract

The exploration of high-performance electrocatalysts for the oxygen evolution reaction (OER) is crucial and urgent for the fast development of green and renewable hydrogen energy. Herein, an ultra-fast and energy-efficient preparation strategy (microwave-assisted rapid in-situ pyrolysis of organometallic compounds induced by carbon nanotube (CNT)) is developed to obtain iron/carbon (Fe/C) heterogeneous materials (Fe/Fe₃C particles wrapped by carbon coating layer). The thickness of the carbon coating layer can be adjusted by changing the content and form of carbon in the metal sources during the fast preparation process. Fe/Fe₃C-A@CNT using iron acetylacetonate as metal sources possesses unique Fe/C heterogeneous, small Fe/Fe₃C particles encapsulated by the thin carbon coating layer (1.77 nm), and obtains the optimal electron penetration effect. The electron penetration effect derives from the redistribution of charge between the surface carbon coating layer and inner Fe/Fe₃C nanoparticles efficiently improving both catalytic activity and stability. Therefore, Fe/Fe₃C-A@CNT shows efficient OER catalytic activity, just needing a low overpotential of 292 mV to reach a current density of 10 mA cm^-², and long-lasting stability. More importantly, the unique control strategy for carbon thickness in this work provides more opportunity and perspective to prepare robust metal/carbon-based catalytic materials at the nanoscale.

Keywords: Carbon coating layer; Electro-catalysis; Electron penetration effect; Fe/C heterostructure; Oxygen evolution reaction.