| 摘要 |
<p>PROBLEM TO BE SOLVED: To produce an amorphous silica molded product having high proton conductance and chemical durability and sparingly lowering membrane strength, etc., even at a higher temperature by including a specific amount of phosphorus pentoxide and by specifying the conductance at a specific temperature so as to have a specific value or a larger one. SOLUTION: This molded product has a composition comprising >=10 mol% phosphorus pentoxide (preferably 10-50 mol% phosphorus pentoxide and 90-50 mol% silica), and has >=10 mS/cm conductance at 50 deg.C and preferably >=10 m2/g specific surface area. The molded product is preferably produced by mixing a silica raw material (e.g. tetramethoxysilane) with a phosphorus raw material (e.g. trimethoxyphosphoric acid), by adding water, by leaving the mixture as it is at room temperature to cause gelation, by heating it up to 100-1,000 deg.C. The form of the molded product is membrane-like, film-like, sheet-like or the like and the thickness is 0.01-20 mm. The molded product has high proton conductance at a temperature ranging from room temperature to 200 deg.C and is stable even at >=100 deg.C.</p> |
