CATALYST LAYER, MEMBRANE ELECTRODE ASSEMBLY, AND ELECTROCHEMICAL CELL

摘要

PURPOSE: A catalyst layer with a layered structure is provide to able to improve durability and use efficiency in an electrode of a membrane electrode assembly, especially cycle durability. CONSTITUTION: A catalyst layer(1) comprises a layered structure on which sheet-like unit catalyst(2), and a pore layer(3) are laminated. An average thickness of the sheet-shaped unit catalysts is 4-30 nm. A porous layer is inserted between two sheet-like unit catalysts. The sheet-like unit catalyst consists of a layered structure that laminated in a transverse direction of the sheet-like unit catalyst. The sheet-like unit catalyst comprises three or more layers laminated in the transverse direction. The outermost layer of the layered structure comprises at least one precious metal and has a composition different with a composition of an inner layer inserted between the outermost layers.