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 po ssible to measure directly the Li+/Li(s) couple at a tungsten electrod e. From open-circuit potential measurements performed in a large numbe r 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 ne utral AlCl3:DMPIC:NaCl (DMPIC = 1,2-dimethyl-3-propylimidazolium chlor ide), a Na+/Na(s) standard reduction potential of -2.097 (+/-0.050) V is directly determined.