The effect of morphological difference and hydride incorporation on the activity of Pd/C catalysts in direct alkaline formate fuel cell

Abstract

Palladium (Pd) on carbon support, electron-enriched by hydrogen incorporation (Pd-H/C), is synthesized via dimethylamine borane complex at multiple temperatures and used for the oxidation of formate (HCOO−). The electronic effect of H is confirmed by physicochemical and electrochemical analysis. Physicochemical analysis revealed no significant changes in the Pd-H/C structures, with changes only in the particle size and dispersion. Pd-H/C 0 °C showed the best catalytic activity for the oxidation of HCOO−, even though it possesses the less electrochemical surface area than commercial Pd/C. Its remarkable power density of 272 mW cm−2 at the nominal cell voltage of 0.5 V is recorded in single cell operation. The observed performance is attributed to the electronic effect brought by the incorporation of H in the Pd lattice. Still the electronic effect of H does not always compensate for the small ECSA caused by large particle size and severe agglomeration. © 2019 Elsevier B.V.