Polymer electrolyte membrane with functionalized nanoparticles

Abstract

The present invention relates to a polymer electrolyte membrane for fuel cells, comprising a polymer matrix of at least one basic polymer and one or more doping agents, wherein particles containing ionogenic groups and having a mean particle diameter in the nanometer range are embedded in the polymer matrix and the particles containing ionogenic groups are distributed homogeneously in the polymer matrix in a concentration of less than 50% relative to the weight of the polymer matrix, as well as to the production and use of same, especially in high-temperature fuel cells.

We claim: 
     
         1 . A method for production of a polymer electrolyte membrane for high temperature fuel cells in a temperature range up to approximately 200° C.,
 the polymer electrolyte membrane comprising a polymer matrix, wherein the polymer matrix comprises at least one basic polymer, one or more doping agents, and particles containing ionogenic groups and having a mean particle diameter in the nanometer range, wherein said particles are embedded in the polymer matrix and are distributed homogeneously in the polymer matrix in a concentration of less than 50% relative to the weight of the polymer matrix, 
 the method comprising: 
 (a) producing a membrane casting solution, at least comprising a solvent, at least one matrix-forming basic polymer and particles containing ionogenic groups, 
 (b) casting the membrane casting solution in the form of a membrane and 
 (c) removing the solvent. 
 
     
     
         2 . A method according to  claim 1 , wherein the membrane is doped after step c) with at least one doping agent in a further step d). 
     
     
         3 . A method according to  claim 2 , wherein the doping agent with which the membrane is doped in step d) is selected from the group comprising phosphoric acid, phosphoric acid derivatives, phosphonic acid, phosphonic acid derivatives, sulfuric acid, sulfuric acid derivatives, sulfonic acid, sulfonic acid derivatives or a combination of two or more thereof. 
     
     
         4 . A method according to  claim 3 , wherein solvent is selected from the group comprising N-methylpyrrolidone (NMP), dimethylformamide (DMF), dimethyl sulfoxide (DMSO), dimethylacetamide (DMAc) and any desired mixtures thereof. 
     
     
         5 . A method according to  claim 3 , wherein removal of the solvent is achieved by heating the cast membrane casting solution and/or by applying a vacuum.