ELECTROCHEMICAL SULFUR-DIOXIDE OXIDATION WITH PLATINUM ALUMINUM ELECTROCATALYSTS

Platinum-aluminum electrocatalysts supported on carbon black were inve stigated for electrogenerative sulfur dioxide (SO2) oxidation in hybri d type, liquid-phase SO2/O-2 cells. Incorporation of aluminum with pla tinum electrocatalysts on carbon resulted in an electrocatalytic activ ity increase for SO2 oxidation over the whole investigated range (1-30 at % aluminum). Significant synergistic effect from aluminum was obse rved when even a small amount, as little as 1 at %, was incorporated i n the platinum. A maximum 68% improvement was obtained when 10 at % al uminum was incorporated in the platinum. Results of an ESCA study and electrochemical platinum surface area measurement supported the hypoth esis of an electronic interaction between platinum and aluminum.