Enhanced utilization and durability of Pt nanoparticles supported on sulfonated carbon nanotubes

•The sulfonic group has been successfully linked onto the CNTs surface.•The Pt/SO3H–Ar–CNTs exhibits high Pt utilization and low Nafion dependence.•The durability of the Pt/SO3H–Ar–CNTs has been greatly improved.

We have synthesized a hybrid catalyst with the high Pt utilization and durability, in which the Pt nanoparticles are deposited on the sulfonated carbon nanotubes (SO3H–Ar–CNTs) with conducting proton and electron. Electrochemical performance of the catalyst (Pt/SO3H–Ar–CNTs) is evaluated by the cyclic voltammograms, linear sweep voltammetry and fuel cell tests, respectively. The experimental results demonstrate that the Pt/SO3H–Ar–CNTs catalyst exhibits good oxygen reduction reaction activity, enhanced durability and excellent Pt utilization compared with the Pt/COOH–CNTs catalyst. The improved performance of Pt/SO3H–Ar–CNTs catalyst is ascribed to the introduction of the sulfonic acid group onto the CNTs surface by the covalent modification method, which ensures Pt NPs locate in triple-phase zones to increase Pt utilization and reduces the corrosion of the SO3H–Ar–CNTs.