[1Ea07-12] SU/EN

[1Ea11S] Investigation of MnO_x OER electrocatalyst including alkali metal ions by operando XAS observation

*Shun Tsunekawa¹, Masaaki Yoshida¹ (1. Yamaguchi University)

Layered Mn oxide catalysts (M:MnO_x :M=Na, K, Cs) have different oxygen evolution reactions (OERs) activities depending on the alkali metal ions contained in the layers. In this study, the electronic states and local structures of Mn and alkali metal ions were observed by operando XAS measurements using synchrotron radiation X-rays. The results suggested that the alkali metal ions in the layer stabilize the OER active Mn³⁺ site because of the bonding with MnO₆ in the layer. The highly active Cs:MnO_x can stabilize more Mn³⁺ and promote the OERs.