Carbon supported Pt-Sn nanoparticles as anode catalyst for direct borohydride-hydrogen peroxide fuel cell: Electrocatalysis and fuel cell performance

Carbon supported Pt-Sn bimetallic nanoparticles(Pt-Sn/C) are prepared by a modified NaBH4 reduction method in aqueous solution at room temperature, and used as the anode electrocatalyst for direct borohydride-hydrogen peroxide fuel cell (DBHFC). The physical and electrochemical properties of the as-prepared electrocatalysts are investigated by X-ray diffraction (XRD), transmission electron microscopy (TEM), cyclic voltammetry (CV), chronoamperometry (CA) and fuel cell test. XRD results show that the diffraction peaks in Pt-Sn/C catalyst shift slightly to lower 20 values with the increase of Sn content compared with that of Pt/C catalyst, suggesting the formation of Pt-Sn alloying. TEM results show that the morphologies of Pt-Sn bimetallic nanoparticles are uniformly spherical with the particle size of about 3 nm on the carbon surface. Besides, it has been found that the Pt-Sn/C catalysts have much higher catalytic activity for the direct oxidation of BH4- than Pt/C catalyst, especially the Pt67Sn33/C catalyst presents the highest catalytic activity among all as-prepared catalysts. The DBHFC with Pt67Sn33/C anode catalyst and Pt/C cathode catalyst obtains the maximum power density as high as 91.5 mW cm(-2) at 25 degrees C. (C) 2012 Elsevier B.V. All rights reserved.