Influence of TiIV substitution on the properties of a Li1.5Al0.5Ge1.5(PO4)3 nanofiber-based solid electrolyte

Abstract

We report the influence of the partial substitution of Ge with Ti on the properties of NASICON Li_1.5Al_0.5Ge_1.5(PO₄)₃ (LAGP) nanofibers prepared by electrospinning. Replacing a small amount of Ge (up to 20%) with Ti is advantageous for enhancing both the purity and morphology of LAGP fibers, as observed by X-ray diffraction, electron microscopy and nuclear magnetic resonance spectroscopy. When Ti-substituted LAGP (LAGTP) fibers are used as filler to develop composite polymer electrolytes, the ionic conductivity at 20 °C improves by a factor of 1.5 compared to the plain polymer electrolyte. Additionally, above 40 °C the LAGTP fiber-based composite electrolytes were more conductive than the equivalent LAGP fiber-based one. We believe that these findings can make a substantial contribution to optimizing current methods and developing novel synthesis approaches for NASICON based electrolytes.