Colloidal silica has been employed as a support material to disperse Pt and develop Pt-SiO2 composites with electrocatalytic properties. The Pt-SiO2 particles of ratio 1:1 and 2:1 show superior performance towards oxygen reduction reaction (ORR) as these composite particles form an interconnected particle-network and maximize the available electrochemically active area. Upon increasing the Pt content we observe decreased activity as a result of aggregation of particles. The performance of Pt-SiO2, composite particles in H-2-fuel cell arc compared with Pt-black catalyst. (c) 2007 Elsevier B.V. All rights reserved.