| 摘要 |
PROBLEM TO BE SOLVED: To lower an oxygen-concentration overvoltage when normal-pressure air is supplied and provide a high output voltage, by using a composition comprising a perfluorosulfonic-acid polymer and a fluorine-containing ether compound as an electrode-catalyst coating agent used for a gas diffusion electrode. SOLUTION: A membrane/electrode joint body for a solid high-polymer type fuel cell comprises an ion-exchange membrane serving as an electrolyte and a gas diffusion electrode jointed to the ion-exchange membrane. An electrode- catalyst coating agent used for the gas diffusion electrode contains a perfluorosulfonic-acid polymer of 30 to 95 wt.% expressed by an expression I and a fluorine-containing ether compound of 5 to 70 wt.% expressed by an expression II. In the expression I, x=0 to 2, y=2 to 3, and n/m=1 to 10. In the expression II, Rf is a perfluoroalkylene group having the C number of 1 to 3, x and y are perfluoroalkyl groups having the C number of 1 to 5, and k is 1 to 100. The gas diffusion electrode using the electrode-catalyst coating agent is used at least on the side of a cathode. |
