Enhanced oxygen reduction reaction activity through spillover effect by Pt–Y(OH)3/C catalyst in direct methanol fuel cells

Dynamic spillover of metal oxide aided by yttrium hydroxide through its altervalent nature is utilized to develop a new carbon supported Pt–Y(OH)3 hybrid catalyst with varying Pt:Y atomic ratio of 1:1, 2:1 and 3:1 and characterized by X-Ray diffraction and Transmission electron microscopy techniques. Pt–Y/C catalysts exhibit significant improvement in oxygen reduction reaction (ORR) over commercial Pt/C. The effects of composition toward ORR with and without methanol have been studied. Among the various Pt–Y(OH)3/C catalysts, the one with Pt to Y in 3:1 atomic ratio shows the highest activity for ORR in aqueous HClO4 solution without methanol while the one with Pt to Y in 2:1 atomic ratio shows the maximum activity for ORR in presence of methanol. A direct methanol fuel cell (DMFC) employing carbon-supported Pt–Y(OH)3 as the cathode catalyst delivers a peak-power density of 105 mW/cm2 at 70 °C as compared to a peak-power density of 64 mW/cm2 obtained with the DMFC employing carbon-supported Pt catalyst operating under similar conditions.

Dynamic spillover of metal oxide aided by yttrium hydroxide through its altervalent nature is utilized to develop a new carbon supported Pt–Y(OH)3 hybrid catalyst with varying Pt:Y atomic ratio of 1:1, 2:1 and 3:1. They exhibit higher ORR activity (Fig. a) and selectivity in presence of methanol in relation to Pt/C (Fig. b). The maximum performance is observed for the DMFCs with Pt–Y(OH)3 (2:1)/C cathode (Fig. c).Figure optionsDownload as PowerPoint slideHighlights
► Dynamic spillover of metal oxide aided by Y(OH)3 is utilized to develop a new carbon supported Pt–Y(OH)3 hybrid catalyst for ORR.
► The preparation procedure is simple for Pt–Y(OH)3 compared to that for Pt–Y alloy for the same ORR activity.
► The Pt–Y(OH)3/C exhibits ORR activity equivalent to that reported for Pt–Y alloy catalyst.
► Pt–Y(OH)3/C is reported for the first time as a methanol tolerant ORR catalyst for DMFCs.