New perspectives in the surface analysis of energy materials by combined time-of-flight secondary ion mass spectrometry (ToF-SIMS) and high sensitivity low-energy ion scattering (HS-LEIS)

Abstract

Time-of-flight secondary ion mass spectrometry (ToF-SIMS) and low-energy ion scattering (LEIS) are recently attracting great interest in energy materials research due to their capabilities in terms of surface sensitivity and specificity, spatial resolution and their ability to analyse the isotopic chemical composition. This work shows the synergy provided by this powerful combination to further our understanding of the surface chemistry and structure that ultimately determines the electrochemical performance in advanced electro-ceramic materials for energy storage and energy conversion applications. In particular, this novel approach has been applied to the analysis of (Li_3xLa_2/3−x□_1/3−2x)TiO₃ perovskite materials used as the electrolyte in lithium batteries and (La, Sr)₂CoO_4+δ epitaxial thin films used as oxygen electrodes in solid oxide fuel cells and solid oxide electrolysers. The analysis of these two promising materials requires the development and optimisation of new analytical approaches that take advantage of the recent instrumental developments in order to characterise the outermost and near-surfaces at the atomic scale.