苯硫酚盐基溶液的可充镁电池电解液

将4-甲基苯硫酚、4-异丙基苯硫酚和4-甲氧基苯硫酚(RSH)分别与格氏试剂C₂H₅MgCl/THF(四氢呋喃)反应制得的苯硫酚氯化镁(RSMgCl)(分别标记为MBMC、IPBMC和MOBMC)/THF和进一步与Lewis 酸AlCl₃反应制得的(RSMgCl)_n-AlCl₃/THF(n=1，1.5，2)苯硫酚盐基溶液用作可充镁电池电解液，采用循环伏安和恒电流充放电测试研究了电解液的镁沉积-溶出性能和氧化分解电位. 结果表明，苯硫酚上的基团种类和RSMgCl与AlCl₃的比例对其电化学性能有影响. 其中，0.5 mol·L^-1(IPBMC)_1.5-AlCl₃/THF 溶液具有最佳的电化学性能，其氧化分解电位适宜(2.4 V(vs Mg/Mg²⁺))，镁沉积-溶出循环效率稳定，过电位低，电导率较高(2.48 mS·cm^-1)，与正极材料Mo₆S₈兼容性良好，且具有一定的空气稳定性，配制方便，有希望应用于实际的可充镁电池体系中.

Benzenethiolate-Based Solutions for Rechargeable Magnesium Battery Electrolytes

The benzenethiolate-based solutions (RSMgCl)_n-AlCl₃/tetrahydrofuran (THF) (R=4-methylbenzene, 4-isopropylbenzene, 4-methoxybenzene; n=1, 1.5, 2, respectively) were obtained by the simple reaction of benzenethiol compounds with the Grignard reagent C₂H₅MgCl/THF and AlCl₃ in THF, and the electrochemical performance as the rechargeable magnesium battery electrolytes are reported. First, 4-methyl-benzenethiolate magnesium chloride (MBMC)/THF, 4- isopropylbenzenethiolate magnesium chloride (IPBMC)/THF, and 4- methoxybenzenethiolate magnesium chloride (MOBMC)/THF solutions (termed as RSMgCl/THF) were synthesized by the reaction of 4-methylbenzenethiol, 4- isopropylbenzenethiol, and 4- methoxybenzenethiol compounds, respectively, with C₂H₅MgCl/THF via a hydrogen metal-radical exchange with rapid evolution of ethane gas. Furthermore, (RSMgCl)_n-AlCl₃/THF solutions were obtained by the reaction of RSMgCl/THF with AlCl₃/THF at different molar ratios of RSMgCl:AlCl₃. The benzenethiolate-based solutions as electrolytes for rechargeable magnesium batteries were characterized in term of anodic stability and reversibility of magnesium deposition-dissolution using cyclic voltammetry and galvanostatic charge/discharge techniques. Furthermore, the compatibility of the solutions with Mo₆S₈ cathode material was verified using coin cells with a Mo₆S₈ cathode, Mg anode, and benzenethiolate-based electrolyte. It is concluded that both the substituents on benzenethiol and the ratio of RSMgCl:AlCl₃ have an effect on the electrochemical performance. 0.5 mol·L^-1 (IPBMC)_1.5-AlCl₃/ THF shows the best electrochemical performance with 2.4 V (vs Mg/Mg²⁺ ) anodic stability, a low voltage for magnesium deposition-dissolution, a high cycling reversibility, and good compatibility with the Mo₆S₈ cathode. Moreover, the air insensitive character and easy preparation make it a promising candidate for rechargeable battery electrolytes.