| 摘要 |
PURPOSE:To obtain a matrix having good penetration capability and retainability of phosphoric acid and high adherence to an electrode by uniformly kneading an electrolyte retaining material comprising mixed particles containing silicon carbide and metal boride, a binder, and a plasticizer, and forming a sheet, then extracting the plasticizer with a solvent. CONSTITUTION:A pair of gas diffusion electrodes comprising catalyst layers 2a, 2b obtained by applying carbon supported with platinum with water repellent polytetrafluoroethylene serving as a binder are formed on both sides of an electrolyte retaining matrix 3 in which phosphoric acid is retained. They are covered with electrode substrates 1a, 1b such as conductive carbon sheets to form a unit cell 4. The unit cell 4 is placed between reparators 6 each of which has a large number of parallel gas supply grooves 5, and a plurality of these units are stacked. As a metal boride, TiB2, CrB2, ZrB2, NbB2, MoB2, or HfB2 is used. Fluorocarbon resin is used as a binder, and dimethyl phthalate as a plasticizer. The content of SiC is 30-80wt.% based on the matrix. |
