Photo-generation of ultra-small Pt nanoparticles on carbon-titanium dioxide nanotube composites: A novel strategy for efficient ORR activity with low Pt content

Despite extensive work on Pt/C based catalyst materials for fuel cells towards oxygen reduction reaction, the high cost of catalyst is still a major problem for efficient use of fuel cells in daily life. This demands at designing a new electrocatalyst with high catalytic activity for oxygen reduction reaction. In this regard, we present a novel composite material consisting of functionalized acetylene black and TiO2 nanotube (FAB/TNT) as the substrate for Pt as catalyst. Using this novel composite, Pt was decorated using photoreduction process. Due to the presence of photo-electrons all over the conducting part of the material, H2PtCl6 was photo-reduced to Pt nanoparticles with extremely small size similar to 1.6 nm. The material demonstrated that even with as less as 3.5 wt% of Pt, mass activity was found to be 37.5 A/g and specific actitvity was found to be 0.75 A/m(2) which is higher than commercial catalyst, Pt-Vulcan XC-72 (mass activity and specific activity was found to be 10.7 A/g and 0.81 A/m(2), respectively) at 0.85 V vs RHE. (C) 2019 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.