Outstanding hydrogen evolution performance of supported Pt nanoparticles: Incorporation of preformed colloids into mesoporous carbon films

Platinum is the best catalyst known so far for the hydrogen evolution reaction (HER) in acidic environments, but it is also a scarce and expensive resource. Maximizing its performance per metal atom is essential in order to reduce costs. The deposition of small Pt nanoparticles (2-3 nm) onto electrically conductive, highly accessible and stable carbon supports leads to active catalysts. However, blocking of pores and active sites by Nafion, which acts as a binding species, reduces the catalytic activity. Moreover, inaccessible Pt located in micropores diminishes an efficient exploitation of the noble metal. We report a new synthesis approach to ordered mesoporous carbon (OMC) coatings with preformed Pt nanoparticles. The particles are exclusively located inside the mesopores. Furthermore, no Nafion binder is needed. As a consequence, the PtNP/OMC catalyst film outperforms Pt/C catalysts reported in literature particularly at high current densities. PtNP/OMC catalyst films with a geometric Pt loading of 1.6 mu g(pt)/cm(2) achieve a current density of -100 mA/cm(2) at an overpotential of ca. -70 mV. (C) 2018 Elsevier Inc. All rights reserved.