Fabrication and lithium intercalation properties of epitaxial Li2RuO3 thin films

Abstract

Lithium intercalation in a lithium excess layered material Li2RuO3 was investigated using two-dimensional model electrodes with a restricted reaction plane of (002). Li2RuO3 films were synthesized on Al2O3(0001) substrate by a pulsed laser deposition, and X-ray diffraction measurements confirmed epitaxial growth of Li2RuO3(002). Electrochemical characterization using cyclic voltammetry and charge/discharge measurements indicated electrochemical reactions with a discharge capacity of 200mAhg−1 for the film deposited at 400°C followed by post-annealing at 550°C. The electrochemical activity on the (002) plane indicated three-dimensional lithium diffusion in the two-dimensional layered rocksalt structure through the lithium sites in the transition metal layer.