Improve the Activity and Stability of PtCo/C Catalyst by Ionic Liquid in Proton Exchange Membrane Fuel Cell

Ionic liquid ([MTBD][C₄F₉SO₃]) has been explored as a surface modification of PtCo/C catalyst to improve its performance and durability in membrane electrode assembly (MEA). Compared to the pristine catalyst, the incorporation of ionic liquid (IL) increases the oxygen reduction reaction (ORR) activity of PtCo/C and reduces the gas and proton diffusion resistance of the cathode catalyst layer, resulting in considerably improved MEA performance. More importantly, IL largely slows down the ORR activity decay. The PtCo/C-IL outperformed PtCo/C throughout the 30,000 potential cycles test, which is consistent with higher active surface area retention and less Co dissolution of PtCo/C-IL. This work suggests that IL modification can serve as a complementary approach to the development of novel electrocatalysts and electrode structure.