@article{Shen2026, 
author = {Yinlin Shen and Kangjie Xu and Zhirong Zhao-Karger and Xiangyu Zhao},
title = {Tailoring Loose Mg2+ Solvation Structure by Steric and Competitive Solvent Coordination for Fast-Charging Magnesium Batteries},
year = {2026},
journal = {Energy & Environmental Materials},
volume = {9},
number = {1},
keywords = {co-solvents, electrode/electrolyte interface, kinetics, magnesium batteries, solvation structure, steric hindrance},
url = {https://www.sciopen.com/article/10.1002/eem2.70124},
doi = {10.1002/eem2.70124},
abstract = {Magnesium batteries are attracting growing interest as next-generation energy storage technology due to their high safety, cost-effectiveness, and resource abundance. However, their development remains limited by sluggish Mg2+ transport kinetics at the electrode/electrolyte interface. Herein, we propose an electrolyte design strategy that modulates the Mg2+ solvation structure by introducing tetrahydrofuran (THF) as a co-solvent into a borate-based electrolyte, Mg[B(hfip)4] (MBF) in dimethoxyethane (DME). THF, selected from a series of linear and cyclic ethers, has a comparable dielectric constant and donor number to DME, but its cyclic structure introduces steric hindrance that induces competitive coordination with Mg2+. This competition weakens Mg2+ − solvent interactions, yielding a more labile solvation structure and enhanced desolvation kinetics. As a result, Mg‖Mg cells employing the optimized MBF/1D1T electrolyte (DME: THF = 1:1, v:v) exhibit a significantly reduced Mg plating/stripping overpotential of 120 mV at 10 mA cm−2, compared with 316 mV at 8 mA cm−2 with MBF/DME, along with exceptional cycling stability exceeding 1200 h. Furthermore, representative sulfide cathodes such as CuS and VS4 demonstrate faster activation and improved high-rate performance in the presence of MBF/1D1T.}
}