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.%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.
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