Characterization of Chloroclosoborane Acids as Electrolytes for Acid Fuel Cells

The perchloroclosoborane acids, H/sub 2/B/sub 12/Cl/sub 12/ and H/sub 2/B/sub 10/Cl/sub 10/, were prepared in high purity and investigated as alternative electrolytes to H/sub 3/PO/sub 4/ in moderate temperature acid fuel cells. Procedures were developed for the purification of the acids prepared from commercially available salts. The purified acids were characterized by infrared, electronic, NMR, and mass spectroscopy. Concentrated aqueous solutions of the acids were found to have low ionic conductivity and a moderate water vapor pressure. The mono anions, B/sub 12/Cl/sub 12/-and B/sub 10/Cl/sub 10/-, formed from reactions of concentrated aqueous solutions or the solid hydrates of the acids. The B/sub 12/Cl/sub 12//sup 2 -/ and B/sub 10/Cl/sub 10//sup 2 -/ anions were also found to adsorb on electrocatalytic Pt surfaces.