Title: Operando X-ray spectroscopic study on 3D transition metal oxidesas electrochemical catalysts

Abstract

The flexibility of the electronic and crystal structure and chemical versatility of 3d transition metal (TM) oxides have emerged as promising nonprecious metal-based catalysts for many modern energy storage and conversion technologies because of their robustness, low cost, environmental friendliness and accessibility under the environmental atmosphere.Theoretical description of electrochemical processes is too sophisticated even very simple spinel and perovskite. We discuss some simple physics concepts for the design of electrocatalysts for the hydrogen evolution reaction (HER), oxygen evolution reaction (OER) and batteries on interplay of the charge-, spin-, orbital-degrees of freedom of 3D transition elements and show our previous successful operando spectroscopic studies on the 3D transition metal oxides.