title: Improved oxygen reduction cathodes using polyoxometalate cocatalysts.
abstract: We report on the influence of a series of transition-metal-substituted Wells-Dawson (P2W17MnO62(12-n)-; M = WVI, FeII, CoII, RuII) and Keggin (PW12O40(3-) and PCoW11O39(5-) anions on the oxygen reduction reaction (ORR) at Au, Pd, and Pt. Wells-Dawson POMs adsorbed on Au lead to large positive shifts of the ORR potential. The magnitude of the shift depends on the transition metal and is explained using a simple thermodynamic model. The best cathode performance was achieved using a PCoW11O39(5-) cocatalyst and a Pt cathode. The +54 mV positive shift in the ORR potential that we observed is comparable to the performance of the best-known bimetallic catalysts.
authors.affiliation: Department of Chemistry and Biochemistry, Auburn University, Auburn, Alabama 36849-5312, USA.
authors.forename: Anand V
authors.initials: AV
authors.lastname: Sankarraj
authors.forename: Sridevi
authors.initials: S
authors.lastname: Ramakrishnan
authors.forename: Curtis
authors.initials: C
authors.lastname: Shannon