Electrochemical Catalytic Activity in Transition-Metal-Oxide Thin Films

Transition-metal oxides serve as an important platform for the study of condensed matter physics. They exhibit various emergent physical properties including high-temperature superconductivity, colossal magnetoresistance, and multiferroicity. The wide spectrum of physical properties is known to stem from the strong interaction between the four degrees of freedom in the transition-metal oxides, i.e., charge, spin, lattice, and orbital. Technologically, the system shows promising applicability for future opto-electronic materials and has attracted much attention. Furthermore, with the recent surge of interest in sustainable energy and the environment, research on transition-metal oxides is actively being pursued. For example, many transition-metal oxides are known to be suitable for chemical energy storage and conversion, and some of the materials have already been commercially adopted. In particular, theoretical and experimental studies on the electrochemical catalysis of transition-metal oxides with perovskite structures are expected to lead directly to future applications in the energy industry. In this article, we will discuss the correlation between the physical behavior of transition-metal oxides and their electrochemical catalytic activity, which should help us to understand the fundamental mechanism of electrochemical catalysis.