Electrochemical study of vanadia-silica xerogel film

In this report, the sol-gel synthesis and electrochemical properties of a homogeneous multicomponent material composed of vanadium pentoxide xerogel dispersed in a silica matrix are described. The cyclic voltammetric and electrochemical impedance spectroscopy studies demonstrated that the silica matrix provides an improvement of the electrochemical properties mainly in relation to the kinetics of the lithium electroinsertion into the oxide matrix with little decrease of total charge during successive redox cycles. This attractive behavior can be explained by the structural stability produced by the silica matrix that favors the kinetic of V-IV/V-V solid state redox transitions. (C) 2003 Published by Elsevier B.V.