Effect of High Local Diffusive Mass Transfer on Acidic Oxygen Reduction of Pt Catalysis

Wu, W. Z.1; Lin, P. Z.1; Liu, B.1; Xu, J. B.1; Sun, J.1; Zhao, T. S.1,2

2024-06-03

10.1149/1945-7111/ad576e

JOURNAL OF THE ELECTROCHEMICAL SOCIETY   影响因子和分区

0013-4651

1945-7111

In this study, we utilize a platinum ultramicroelectrode as a model platform for platinum electrocatalysts in acidic electrolytes to study the effects of local mass transfer on the oxygen reduction reaction (ORR), which plays a significant role in fuel cells with reduced platinum loading. Finite element simulations show that the UME exhibits size-dependent ultrathin diffusion layers during the electrochemical process. Submicron-scale UMEs can achieve ultrahigh localized mass transfer, which is unattainable through other experimental techniques. By conducting catalytic experiments under various mass transfer conditions, we find that the mass transfer limiting current is significantly lower than the value predicted by the four-electron process equation. Additionally, the apparent electron transfer number (napp) decreases as the mass transfer coefficient (m0) increases. Furthermore, as m0 increases, the half-wave potential shifts toward more negative values, allowing for the evaluation of the intrinsic activity of the catalysts over a broader potential range. Due to the UME technique's capability to conveniently control local mass transfer, we anticipate its potential application in understanding the effects of chemical microenvironments on complex electrochemical reactions, including ORR and other processes.

oxygen reduction reaction (ORR) electrocatalysis ultramicroelectrodes local mass transfer local chemical environments

SCI ; EI

英语

通讯

Research Grants Council of the Hong Kong Special Administrative Region, China[HKUST C6011-20G] ; Guangdong Major Project of Basic and Applied Basic Research[2023B0303000002]

Electrochemistry ; Materials Science

Electrochemistry ; Materials Science, Coatings & Films

WOS:001254828800001

ELECTROCHEMICAL SOC INC

CHEMISTRY

Web of Science

1.Hong Kong Univ Sci & Technol, Dept Mech & Aerosp Engn, Clear Water Bay, Hong Kong, Peoples R China
2.Southern Univ Sci & Technol, Dept Mech & Energy Engn, Shenzhen 518055, Peoples R China

Wu, W. Z.,Lin, P. Z.,Liu, B.,et al. Effect of High Local Diffusive Mass Transfer on Acidic Oxygen Reduction of Pt Catalysis[J]. JOURNAL OF THE ELECTROCHEMICAL SOCIETY,2024,171(6).

Wu, W. Z.,Lin, P. Z.,Liu, B.,Xu, J. B.,Sun, J.,&Zhao, T. S..(2024).Effect of High Local Diffusive Mass Transfer on Acidic Oxygen Reduction of Pt Catalysis.JOURNAL OF THE ELECTROCHEMICAL SOCIETY,171(6).

Wu, W. Z.,et al."Effect of High Local Diffusive Mass Transfer on Acidic Oxygen Reduction of Pt Catalysis".JOURNAL OF THE ELECTROCHEMICAL SOCIETY 171.6(2024).