TEM Observation of LaPO₄-Dispersed LATP Lithium-Ion Conductor

Abstract

We have previously reported that a three-fold increase in lithium-ion conduction can be achieved on LATP (Li₁.₃Al₀.₃Ti₁.₇(PO₄)₃) by dispersing LaPO₄ particles through the co-sintering of LATP with 4 wt% of LLTO (Li₀.₃₄₈La₀.₅₅TiO₃). However, the LaPO₄ formation during sintering has been detected only by means of XRD and back-scattered SEM, and precise morphology of LaPO₄ particles as well as LATP/LaPO₄ interface have still been uncertain. In the present study, we carried out TEM experiments on the LaPO₄-dispersed LATP composite to investigate the detailed microstructure and compositions of the dispersed LaPO₄ particles and surrounding LATP matrix. HR-TEM coupled with EDS reveals that LaPO₄ particle attains an intimate contact with the LATP matrix, which would allow the formation of space charge layer at the interface to enhance the conductivity.