DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT The porous sheet to be used for the fuel cell electrode according to the present invention should desirably have its porosity of, for example, 50% or above (or preferably, 75% or above), As an example, a carbon fiber sheet having thickness in a range of from 30 to 300 .
mu.
m (or preferably, from 50 to 200 .
mu.
m) is excellent.
In case a catalyst adhered layer is provided to the side of the catalyst layer, its thickness should desirably be in a range of, for example, from 10 to 300 .
mu.
m (or preferably from 50 to 150 .
mu.
m); and, in the case of providing a matrix adhered layer to the side of the matrix layer, its thickness should desirably be in a range of, for example, from 30 to 300 .
mu.
m (or preferably from 50 to 200 .
mu.
m).
Total thickness of the entire catalyst layer including the catalyst adhered layer should be in a range of, for example, from 50 to 400 .
mu.
m (or preferably, from 100 to 300 .
mu.
m).
The entire matrix layer including the matrix adhered layer should have its total thickness in a range of, for example, from 50 to 500 .
mu.
m (or preferably, from 100 to 300 .
mu.
m).
The above-mentioned catalyst layer is composed of catalyst powder and a binding agent.
The catalyst powder consists of fine particles of platinum which is carried on the surface of carbon powder.
For the binding agent, fluorine-containing resins such as polytetrafluoroethylene (PTFE), copolymers of tetrafluoroethylene/hexafluoropropylene (hereinafter referred to simply as "FEP"), and others are suitable.
The above-mentioned matrix layer is composed of a matrix skeletal material and a binding agent.
For the matrix skeletal material, use is made of carbon, inorganic compounds, phosphates of metals, and so forth.
Of the inorganic compounds to be used as the matrix skeletal material, there are zirconium oxide, silica alumina, silica-alumina, niobium oxide, tantalum oxide, tungsten oxide, titanium oxide, silicon nitride, boron carbide, tungsten carbide, silicon carbide, and so on, all being in the form of powder or fiber, of which silicon nitride and silicon carbide are excellent
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Fuel Cells 
