TECHNOLOGY FOCUS - ELECTRICAL POWER AND ENERGY - Preferred Assembly: The membrane-electrode assembly has a maximum power density of 90-150 mW/cm2 and a current density (at 0.45 V) of 90-180 mA/cm2 at an operational temperature of 60 degrees C when 1 M methanol fuel and air are fed in a stoichiometric ratio of 2.5 into the electrodes having an area of 13.9 cm2.    TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Components: The spherical silica is colloidal silica dispersed in a solvent and/or dried spherical silica. The spherical silica has a particle diameter of 1 nm to 5 mu m 15 nm to about 1000 nm. Preferred Composition: The composition further comprises a solvent (100-300 parts by weight). Preferred Layer: The catalytic layer contains pores having a diameter of 1 nm to 5 mu m, and has a pore volume of 20-150 cm3/g, a specific surface area of 5-15 m2/g, and a thickness of 10-50 mu m. The catalytic layer is supported by an electrode substrate (preferably carbon paper or cloth). EXAMPLE - Preparation of spherical silica particles was carried out as follows: Tetraethoxysilane (0.3 M) was added to a solution of 1-propanol (3.3 M), methanol (6.3 M), water (15.6 M) and NH3 (2 M). An aqueous solution of NH4OH (average 20 wt.%) was used as the NH3 solution. After stirring at room temperature for 20 minutes, spherical colloidal silica was observed in the solution. The spherical silica particles were separated using a centrifuge and dried in a vacuum oven. The spherical silica particles were found to have an average diameter of 400 nm. Preparation of Catalyst Slurry Composition was carried out as follows: Nafion (RTM: binder) (15 parts by weight) was mixed with a mixed solvent (213 parts by weight) of 1-propanol, ethylene glycol (EG) and distilled water to prepare a binder solution. A PtRu (100 parts by weight) as a catalyst was dispersed in the binder solution to obtain a slurry. The spherical silica (20 parts by weight) produced above was dispersed in the slurry to prepare a catalyst slurry composition for an anode having a solids content of 38 wt.%.