Operando Spectroscopic Study of Oxygen Reduction Reaction using Biomimetic Non-Precious Electrocatalyst in Fuel Cells
Hsiang-Ting Lien1*, Sun-Tang Chang3, Kuei-Hsien Chen1,2, Li-Chyong Chen1
1Center for Condensed Matter Sciences, National Taiwan University, Taipei, Taiwan
2Institute of Atomic and Molecular Science, Academia Sinica, Taipei, Taiwan
3National Synchrotron Radiation Research Center, Hsinchu, Taiwan
* presenting author:Hsiang-Ting Lien, email:htlien@ntu.edu.tw
The progress of fuel cell technologies lies in the development of a low-cost and efficient catalyst that can undergo oxygen reduction reaction (ORR). In our previous studies, we demonstrated that Vitamin B12, a Co-corrin based molecule, could replace platinum as an electrocatalyst in fuel cells. This could lead to a new generation of emission free, low cost hydrogen fuel cells. However, the ORR follows a four- electron pathway that makes it difficult to probe the catalyst using conventional means. Despite obtaining interesting results from ex-situ experiments, we have yet to deduce why certain reaction pathway in our electrocatalyst occurs. Our recent study elucidates the mechanism of ORR in our electrocatalyst using X-ray techniques under operating conditions ("in operando”). In-situ K edge and L edge XAS combined with electrochemical impedance spectroscopy gave us powerful evidences to prove the mechanism of our electrocatalyst’s ORR pathway which relies on the non-bonding interaction of O2 with our electrocatayst.

Keywords: Operando Spectroscopy, X-ray Absorption, Energy Conversion