Observing the Structural Evolution of Quasi-Monolayer Pt Shell on Pd Core in the Electrocatalytic Oxygen-Reduction Reaction

Yan Dong; Zhenlan Li; Guocheng Zheng; Jiawei Zhang; Jiawei Zhou; Yuki Orikasa; Yoshiharu Uchimoto; Xiaoming Wang

doi:10.1021/acs.jpclett.3c01598

Observing the Structural Evolution of Quasi-Monolayer Pt Shell on Pd Core in the Electrocatalytic Oxygen-Reduction Reaction

J Phys Chem Lett. 2023 Aug 10;14(31):7027-7031. doi: 10.1021/acs.jpclett.3c01598. Epub 2023 Jul 31.

Authors

Yan Dong¹, Zhenlan Li¹, Guocheng Zheng¹, Jiawei Zhang¹, Jiawei Zhou¹, Yuki Orikasa², Yoshiharu Uchimoto³, Xiaoming Wang¹

Affiliations

¹ College of Chemistry and Chemical Engineering, Key Laboratory for Preparation and Application of Ordered Structural Materials of Guangdong Province, Shantou University, Shantou 515063, China.
² College of Life Sciences, Ritsumeikan University, Shiga 525-8577, Japan.
³ Graduate School of Human and Environmental Studies, Kyoto University, Kyoto 606-8501, Japan.

PMID: 37523861
DOI: 10.1021/acs.jpclett.3c01598

Abstract

The use of a quasi-monolayer Pt shell (Pt_qms) on a Pd core (Pd_c) can reach cost and activity targets for the electrocatalytic oxygen-reduction reaction (ORR). The structure of Pd_cPt_qms in the ORR will vary; however, direct observation of this issue is scarce. Here, during cyclic staircase voltammetry (ranging from 0.5 to 1.15 V_RHE) in 0.1 M O₂-saturated HClO₄, the structure of Pd_cPt_qms was monitored by in situ X-ray absorption spectroscopy. The qualitative and quantitative structural information clearly exhibits a complete picture that Pt_qms will directly restructure to form Pt clusters and holes, while Pd_c almost remains stable. These findings identify the initial structural evolution of Pd_cPt_qms in the ORR, highlighting the importance of protecting Pd_c in the development of high-performance Pd_cPt_qms electrocatalysts.