Preparation method of catalyst coating film for high gas transmission and high proton conduction of fuel cell

The invention discloses a preparation method of a catalyst coating film for high gas transmission and high proton conduction of a fuel cell, and relates to a preparation method of a catalyst coating film of a fuel cell. The invention aims to solve the technical problems of slow transmission of reaction gas in a catalyst layer of the existing fuel cell catalyst coating film and slow conduction of protons to Pt active sites in carbon carrier holes. The preparation method comprises the following steps: 1, preparing a porous carbon nanocage; 2, preparing a porous carbon nanocage coated with a perfluorosulfonic acid ionomer; 3, hydroxyl functionalized ionic liquid 1-(2-hydroxyethyl)-3-methylimidazolium bis (trifluoromethylsulfonyl) imine salt is prepared; 2, hydroxyl functionalized ionic liquid 1-(2-hydroxyethyl)-3-methylimidazolium bis (trifluoromethylsulfonyl) imine salt is prepared; 4, preparing a Pt/C catalyst impregnated with the hydroxyl functionalized ionic liquid; 5, preparing slurry; and 6, coating and dr