Changes in electronic structure upon lithium insertion reaction into the A-site-deficient perovskite-type oxides, Gd1/3TaO3: Part 1. XAS measurements

Electrochemical behavior and the variation of electronic structure upon lithium insertion into the A-site-deficient perovskite oxide, Gd1/3TaO3, have been studied by X-ray absorption spectroscopy (XAS). During electrochemical lithium insertion, Gd LIII-edge and Ta LI-edge XAS revealed that Gd ion did not contribute the charge compensation, while Ta ion reduced its oxidation state. Furthermore, the changes in O K-edge spectra with electrochemical lithium insertion were clearly observed, indicating that O ions also contribute to the electron-transfer reaction.