Synthesis and Durability of Highly Dispersed Platinum Nanoparticles Supported on Ordered Mesoporous Carbon and Their Electrocatalytic Properties for Ethanol Oxidation

摘要

In this work, we develop a novel method to prepare a well-dispersed platinum precursor in the modified mesoporous carbon-46 (MPC) by using a simple melt-diffusion strategy. After the Pt precursor was reduced by hydrogen gas, almost 100% platinum nanoparticle catalysts (Pt/MPC) were confined in the pores of MPC. Physical (XRD, HRTEM, and BET), electrochemical, and in situ FTIR spectroscopic methods were used to investigate the properties of the Pt/MPC. The HRTEM image illustrates that Pt nanoparticles (NPs) of ca. 2—3 nm are loaded inside the small mesopores of the pore walls and NPs of da. 5—6 nm are in the mesochannels of the MPC, and the Pt loading in Pt/MPC is 35 wt %. In comparison with the commercial Pt/C catalysts (40 wt %, Johnson Matthey), the Pt/MPC displays a high activity toward ethanol oxidation. The Pt/MPC exhibits also a high durability after a long-time potential scan: the loss of catalytic surface area.is only 4.73% for Pt/MPC, whereas it is 14.75% for Pt/C. Moreover, in situ FTIR studies demonstrate that the Pt/MPC can promote the cleavage of the C—C bond of ethanol.