Diffusion processes at photoemission from lithium into its passivating layer

The pulse laser technique was employed to study the kinetics of the diffusi on processes which follow electron photoinjection from metallic lithium int o the solid electrolyte passivating film on the lithium I solution interfac e. Solutions of LiClO4, LiAsF6, and LiPF6 in the mixed solvents propylene c arbonate + dimethoxyethane and ethylene carbonate + diethyl carbonate were used. A systematic comparison of the experimental photopotential relaxation curves recorded under various experimental conditions (temperature, film t hickness and conductivity) with the corresponding theoretical equations was performed. The electron emission length (about I nm) has been estimated. T he electron diffusion coefficient and activation energy of diffusion calcul ated from out transient photopotential curves have been found to be close t o these values related to the ionic carriers in the solid electrolyte layer . A possible mechanism of photoelectron transfer in the solid electrolyte l ayer on lithium is discussed. (C) 2001 Elsevier Science Ltd. All rights res erved.