Effect of particle size of carbon catalyst on oxygen reduction activity for fuel cell applications

2nd International Workshop on Materials Science and Mechanical Engineering

机械制造;材料科学

Suo, N.^1 ; Ren, Y.^2 ; Huang, H.^1 ; Wu, A.M.^1 ; Zhang, G.F.^1

Key Laboratory of Materials Modification by Laser, Ion and Electron Beams (Ministry of Education), School of Materials Science and Engineering, Dalian University of Technology, Liaoning Province, Dalian

116024, China^1

School of Materials Science and Engineering, Henan University of Technology, Henan Province, Zhengzhou

450001, China^2

关键词: Alkaline solutions;    Carbon catalysts;    Electrocatalytic behavior;    Fuel cell application;    Graphite particle size;    Methanol tolerance;    Oxygen reduction reaction;    Rotating disk electrodes;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/504/1/012025/pdf
DOI  :  10.1088/1757-899X/504/1/012025

学科分类：材料科学（综合）

来源: IOP

【 摘 要 】

Graphite powders with particle sizes of 40, 100, 400, and 1000 nm were used as cathode catalysts. The influence of graphite particle size on the electrocatalytic behavior towards the oxygen reduction reaction (ORR) was investigated. The catalytic activity and kinetics of the ORR, and methanol tolerance were tested in alkaline solutions with saturated oxygen via cyclic voltammetry (CV), rotating disk electrode (RDE) and amperometric i-t curve techniques. Experimental results show that the ORR process of the graphite catalyst with a particle size of 40 nm was close to the four-electron pathway at -0.6 V, exhibiting the best ORR activity. This is ascribed to a greater number of edge defects as ORR active sites in the carbonmaterial. The number of sites can be characterized with X-ray diffraction (XRD) and Raman spectroscopy. Additionally, these graphite catalysts have been demonstrated a superior tolerance to methanol than the commercial 20 wt.% Pt/C electrode in alkaline solutions.