A facile surfactant-assisted synthesis of carbon-supported dendritic Pt nanoparticles with high electrocatalytic performance for the oxygen reduction reaction

摘要

Dendritic platinum (Pt) nanoparticles are successfully anchored on Ketjen Black by a facile synthetic route without organic solvent. The nonionic surfactant Brij 58 is used as a mesopore-forming agent during the in-situ growth of Pt nanoparticles. The dendritic Pt nanoparticles on Ketjen Black exhibit highly efficient electrocatalytic activity for the oxygen reduction reaction. The electrocatalytic activity can be further improved by increasing the Pt loading amount on Ketjen Black. Upon increasing to 31.4 wt% Pt, the half-wave potential and limited-diffusion current density reach 0.887 V and 6.22 mA cm(-2), respectively. The as-prepared catalyst shows an ideal four-electron pathway of O-2 reduction to H2O and a low H2O2 yield of less than 1% in the potential window of 0.2-0.8 V. Moreover, the catalyst exhibits remarkable long-term durability with the same limiting current density and only a 10.5 mV negative shift in the half-wave potential after 5000 cycles.