| 摘要 |
1316751 Making gas diffusion electrodes DEFENCE SECRETARY OF STATE FOR 4 Aug 1970 [7 Oct 1969] 49243/69 Heading B3A [Also in Divisions G1 and H1] A gas diffusion electrode is made by applying a non-conducting gas permeable material to a liquid permeable metal sinter and subjecting them to heat and pressure to cause the gas permeable material to form a layer which is impermeable to liquids. The electrode can be used in an oxygen sensor, fuel cell or air-depolarized electrical power source. The liquid permeable metal sinter may be of silver, gold, copper or nickel and the gas permeable layer may be of P.T.F.E., polyethylene, polypropylene, regenerated cellulose foil or graft copolymers thereof. In an example, a thin film of P.T.F.E. and a silver sinter are subjected to a pressure of 0À2 tons/cm.<SP>2</SP> at 350‹ C. to join the P.T.F.E. to the sinter. In another example, an aqueous suspension of P.T.F.E. is sprayed on to the silver sinter, and the water removed by heating the sinter to 350‹ C., after which the P.T.F.E. is bound to the silver sinter by a pressing operation. |
