Highly active and stable platinum catalysts for propane combustion were prepared by impregnating platinum on zirconia-incorporated silica by combining the high surface area of silica with the exceptional thermal stability of zirconia. The thermal stability of the platinum catalysts was examined after thermal aging at 800 A degrees C for 50 h. The physico-chemical states of the platinum and zirconia were investigated by using various analytical instruments, CO and H-2 chemisorption, and temperature-programmed-desorption of ammonia. The platinum catalysts prepared on the zirconia-incorporated silica and treated with hydrogen peroxide showed high catalytic activity and stability in propane combustion. The high dispersion of platinum and the acid site generation achieved due to the incorporation of zirconia on the silica were responsible for the high activity and stability of the catalysts. Highly active and stable platinum catalysts for propane combustion were prepared by impregnating platinum on zirconia-incorporated silica by combining the high surface area of silica with the exceptional thermal stability of zirconia. The platinum catalysts supported on zirconia-incorporated silica maintained their activity after thermal aging at 800 A degrees C for 50 h.