Synthesis of magnesium chloride complex electrolyte: Galvanic couple assisted catalytic dissolution of magnesium in ethereal solution

Jung Hoon Ha, Jinwon Cho, Jong Hak Kim, Byung Won Cho, Hyung Chul Ham, Si Hyoung Oh

Research output: Contribution to journalArticle


Herein, we reveal the critical role of CrCl3 and the mechanism for the synthesis of magnesium chloride complex (MaCC), an advanced conditioning-free electrolyte for rechargeable magnesium batteries. This involves a catalytic dissolution of Mg metal by nanoscale bimetallic galvanic couples in an ethereal solution: At the initial stage, nanoscale amorphous Cr-rich ‘islands’ form on Mg surface, creating numerous Cr-Mg galvanic couples. These Cr-rich islands act as local cathodic sites due to partial electron transfer from Mg metal substrate. Furthermore, the first-principles calculation shows that Al prefers to bind at Cr-rich regions rather than Mg. These trigger a heterogeneous catalysis for the selective deposition of Al on Cr-rich islands and a dramatic increase in the dissolution rate of Mg metal on the neighboring region. This leads to an ultrahigh Mg2+-to-Al3+ concentration ratio in the resultant solution, a key property of the conditioning-free electrolyte. This study is potentially applicable to many other fields like metal-air batteries and corrosion protection of metals, where a subtle manipulation of passive layer is required.

Original languageEnglish
Pages (from-to)120-127
Number of pages8
JournalJournal of Power Sources
Publication statusPublished - 2018 Sep 15


All Science Journal Classification (ASJC) codes

  • Renewable Energy, Sustainability and the Environment
  • Energy Engineering and Power Technology
  • Physical and Theoretical Chemistry
  • Electrical and Electronic Engineering

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