TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Component: The catalyst is sodium carbonate, ammonium bicarbonate, ammonium carbonate, sodium bicarbonate, and/or calcium hydroxide. Preferred Method: The protective gas is nitrogen, helium, or argon gas.    TECHNOLOGY FOCUS - METALLURGY - Preferred Component: The platinum/carbon aerogel catalyst includes platinum (20-40 wt.%).    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Component: The carbon aerogel is prepared from hydroxyphenol, formaldehyde, and catalyst. The molar ratio of hydroxyphenol to formaldehyde is 1:1-2. The molar ratio of hydroxyphenol to catalyst is 1:100-1500. Preferred Method: Ultrasonic dispersing comprises ultrasonically stirring ethylene glycol solution of hexachloroplatinic acid (H2PtCl6) for 15-45 minutes; adding carbon aerogel in the solution and ultrasonically dispersing for 15-45 minutes; finally adjusting the pH at 8-12, preferably 9-10 with alkaline solution; and ultrasonically dispersing the solution for 15-45 minutes. Intermittent heating with microwave oven comprises holding the mixed solution in microwave oven and microwave heating repeatedly for 15-22 seconds for 5-8 times at an interval of 8-10 seconds. The carbon aerogel is prepared by adding hydroxyphenol, formaldehyde, and catalyst in water; mixing and stirring the mixture uniformly and placing the mixture in a sealed container; standing the mixture for 3-7 days at 80-90 degrees C to obtain organic aerogel; placing the organic aerogel in 1-3 vol.% acetic acid solution; standing the mixture for 1-3 days at normal temperature; taking out the mixture and placing for 2-4 days in acetone, which is replaced once every day; taking out the mixture; drying at normal temperature and normal pressure; grinding the powder to obtain carbon aerogel powder; slowly heating the carbon aerogel powder in protective gas atmosphere until the temperature is increased to 900-1100 degrees C, where temperature is slowly increased to 200-300 degrees C within 1-2 hours, maintained for 1-2.5 hours, increased to 380-500 degrees C within 0.5-1.5 hours, and increased to 900-1100 degrees C within 1.5-3.5 hours; keeping the temperature at 900-1100 degrees C for 3-5 hours; and cooling the powder until the temperature is decreased to room temperature to obtain the carbon aerogel.