Ball milling enables phase-pure synthesis of a temperature sensitive ternary chloride, MgZrCl$_6$

Christopher L. Rom; Austin Shotwell; Sinclair Combs; Autumn Peters; Lauren Borgia; James R. Neilson; Annalise E. Maughan

paper

Ball milling enables phase-pure synthesis of a temperature sensitive ternary chloride, MgZrCl $_{6}$

arXiv:2508.16066

Abstract

Ball milling is a powerful synthetic tool for discovering new inorganic materials. Inspired by the high ionic conductivity in Li $_{2}$ ZrCl $_{6}$ synthesized via mechanochemistry, we synthesized MgZrCl $_{6}$ with a similar method. High resolution synchrotron X-ray diffraction shows that MgZrCl $_{6}$ is poorly crystalline after ball milling, but crystallizes in a layered hexagonal structure ( $P 31 c$ ) after heat treatment. In situ synchrotron X-ray diffraction reveals a narrow temperature window around 400 °C in which crystallization occurs. At higher temperatures the phase decomposes. Pair distribution function analysis shows 2D sheets of MgZrCl $_{6}$ form after milling, with heating driving 3D crystallization. Raman spectroscopy also shows evidence of MgZrCl $_{6}$ after milling. Electrochemical impedance spectroscopy does not reveal ionic conductivity in MgZrCl $_{6}$ (limit of detection ca. $1.4 \times 1 0^{- 8}$ S/cm). In addition to supporting existing design rules for Mg-based solid electrolytes, this work shows the power of ball milling to synthesize temperature-sensitive inorganic compounds with high yield.

Ball milling enables phase-pure synthesis of a temperature sensitive ternary chloride, MgZrCl6​

Abstract

Ball milling enables phase-pure synthesis of a temperature sensitive ternary chloride, MgZrCl $_{6}$