Stability of platinum nanoparticles supported on surface-treated carbon black

Platinum nanoparticles supported on carbon black (CB) are used as electrocatalysts in polymer electrolyte fuel cells, and their stability is important for the durability of the catalyst system. Here, we investigated the stability of Pt nanoparticles supported on surface-treated CB with a thermochemically developed surface nanostructure. The protruding structure of surface-treated CB was able to support Pt nanoparticles synthesized via the sodium tetrahydroborate (NaBH4) reduction of hexachloroplatinic(IV) acid hexahydrate (H2PtCl6∙6H2O) with polyvinylpyrrolidone (PVP). The dependence of Pt stability on the deposition locations on the CB surface was examined using in situ transmission electron microscope observations during heating up to 800°C. We found that the protruding parts on the CB surface function as local sites for stably supporting Pt nanoparticles. Hence, we suggest that the stability of the Pt nanoparticles can be improved using the CB surface nanostructure.