Method of making an electrolyte-permeable, heterogeneous polymer sheet for a gas diffusion composite electrode

摘要

A gas diffusion composite electrode is disclosed which is suitable for use in combination with an electrically conductive current collector. The electrode comprises an electrochemically active, porous and heterogeneous layer containing (1) an interconnected, hydrophilic island material comprising a blend of a major amount of an electrically conductive, particulate material, such as carbon black, in combination with an electrochemically active catalyst, and a minor amount of a hydrophobic polymer in combination with (2) a hydrophobic matrix material consisting essentially of a hydrophobic polymer rendered substantially porous by removal of a pore-forming ingredient. Methods of preparing the heterogeneous layer and the composite electrode are also disclosed.