LITHIUM AND SODIUM STANDARD REDUCTION POTENTIALS IN AMBIENT-TEMPERATURE CHLOROALUMINATE MOLTEN-SALTS

By adding HCl2- to buffered neutral AlCl3:MEIC:LiCl (MEIC = 1-methyl-3-ethylimidazolium chloride) ambient-temperature molten salts, it is possible to measure directly the Li+/Li(s) couple at a tungsten electrode. From open-circuit potential measurements performed in a large number of AlCl3:MEIC:LiCl buffered melts, the Li+/Li(s) standard reduction potential is found to be -2.066(+/-0.005) V vs. Al(III)/Al in a 1.5:1.0 AlCl3:MEIC reference melt. Similarly, by adding HCl2- to buffered neutral AlCl3:DMPIC:NaCl (DMPIC = 1,2-dimethyl-3-propylimidazolium chloride), a Na+/Na(s) standard reduction potential of -2.097 (+/-0.050) V is directly determined.