TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Components: The support particles comprise carbon black. The carbon black is Vulcan XC72 (RTM: Carbon black), Vulcan XC605 (RTM: Carbon black), Monarch 700 (RTM: Carbon black), Monarch 1100 (RTM: Carbon black) and Ketjen Black EC600 (RTM: Carbon black). The active phase precursor comprises a metal-containing compound comprising a metal selected from nickel, cobalt, iron, copper, manganese, chromium, ruthenium, rhenium, molybdenum, tungsten, vanadium, zinc, titanium, zirconium, tantalum, iridium, platinum, palladium and gold.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Method: The precursor composition is high shear mixed prior to the aerosolizing. Preferred Components: The catalyst particles have a tap density of less than 0.65 g/m3, preferably of less than 0.50 g/m3. The precursor composition further comprises a dispersant. The dispersant comprises methylcellulose. The catalyst particles have a Brunauer-Emmett-Teller nitrogen surface area of 200-500 m2/g. The precursor composition comprises the defoamer in an amount of less than about 1.2 wt.%. The precursor composition: is substantially free of defoamer; or comprises the defoamer in an amount of greater than about 0.01 wt.% and less than about 2 wt.%, preferably less than about 0.5 wt.%.    TECHNOLOGY FOCUS - POLYMERS - Preferred Components: The defoamer is Surfynol DF 11OD (RTM: Defoamer) and a polyglycol. The defoamer comprises a polyol. EXAMPLE - To Ketjen Black EC600 (RTM: Carbon black) (84.84 g) in a high shear mixer containing some water, Methocel E3 (RTM: Methylcellulose) (Dow Chemical) (14.37 g) and Surfynol DF 110 D (RTM: Defoamer) (0.79 g). The resulting mixture was processed to disperse the carbon using the cellulose-dispersing agent and enough deionized water was added to make up 4.55% carbon loading in the dispersion. A desired amount of platinum precursor was mixed with the carbon black dispersion under the shearing conditions and the solution at 4% solid loading was pumped into the spray conversion reactor under the controlled conditions. The obtained catalyst particles have a low tap density, high surface area and high pore volume. Further the catalyst was irregular in shape and was ideal for use in a hydrogen air fuel cell.