Ionic liquid modified fct-PtCo/C@ILs as high activity and durability electrocatalyst for oxygen reduction reaction

The catalyst with an ionic liquid layer (fct-PtCo/C@ILs) is prepared by modifying the chemically ordered platinum-cobalt catalyst (fct-PtCo/C) using hydrophobic ionic liquid 1butyl-3-methyl imidazolium bis [(trifluoromethyl) sulfonyl] imide ([BMIM] [TFSI]) with high oxygen solubility. According to TEM, FTIR, XPS and TGA measurements, it is confirmed that the ionic liquid has modified the surface of chemically ordered PtCo/C catalyst. The results reveal that the mass activity and specific activity of fct-PtCo/C@ILs catalyst (ILs loading of 5 wt%) reaches 1.04 A mgPtxe003;1 and 1.4 mA cmPtxe003;2, respectively, which are about 8.7 and 7 times higher than that of the commercial Pt/C catalyst. Compared with the catalysts without ILs modification, fct-PtCo/C@ILs shows significantly enhanced electrochemical durability and a higher power density. The addition of ionic liquid can reduce the generation of oxygenated species and promote the release of catalytic active sites. Subsequently, the conductive layer of ionic liquid is formed on the catalyst surfaces, inhibiting the dissolution of metal nanoparticles and the corrosion of carbon supports in acidic electrolytes through physical protection. (c) 2021 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

Automated summary

A catalyst with an ionic liquid layer, fct-PtCo/C@ILs, was prepared by modifying the chemically ordered platinum-cobalt catalyst, fct-PtCo/C, using a hydrophobic ionic liquid, [BMIM] [TFSI], with high oxygen solubility. The modified catalyst showed significantly improved mass activity, specific activity, electrochemical durability, and power density compared to the commercial Pt/C catalyst. The addition of the ionic liquid reduced the generation of oxygenated species and promoted the release of catalytic active sites, resulting in the formation of a conductive layer that protected the catalyst surfaces from dissolution and corrosion.