▎ 摘　　要

NOVELTY - Low-temperature carbon monoxide and formaldehyde cross-sensitive material comprises composite powder material comprising 15-20 wt.% cobalt monoxide and 15-20 wt.% niobium pentoxide doped with 0.6-1.2 wt.% platinum supported by 61-69 wt.% graphene. The cross-sensitive material is prepared by e.g. slowly adding natural graphite to 15 wt.% hydrogen peroxide aqueous solution under continuous stirring conditions, adding 2/3 the weight of natural graphite potassium permanganate and the same weight of concentrated sulfuric acid as natural graphite, warming up to 55-60 degrees C, continuously stirring for 5 hours, naturally cooling to room temperature, filtering with suction and washing the filtrate with water to neutrality to obtain mixture A, co-dissolving the easily soluble cobalt salt and ammonium niobium oxalate in 10% aqueous hydrochloric acid solution, heating to 50 degrees C, adding sorbic acid under high-speed stirring to keep the solution clear, and cooling to room temperature. USE - Used as low-temperature carbon monoxide and formaldehyde cross-sensitive material. ADVANTAGE - The cross-sensitive material measures the trace amount of carbon monoxide and formaldehyde in the air with high sensitivity at lower temperature without interference from other common coexisting molecules. DETAILED DESCRIPTION - Low-temperature carbon monoxide and formaldehyde cross-sensitive material comprises composite powder material comprising 15-20 wt.% cobalt monoxide and 15-20 wt.% niobium pentoxide doped with 0.6-1.2 wt.% platinum supported by 61-69 wt.% graphene. The cross-sensitive material is prepared by slowly adding natural graphite to 15 wt.% hydrogen peroxide aqueous solution under continuous stirring conditions, adding 2/3 the weight of natural graphite potassium permanganate and the same weight of concentrated sulfuric acid as natural graphite, warming up to 55-60 degrees C, continuously stirring for 5 hours, naturally cooling to room temperature, filtering with suction and washing the filtrate with water to neutrality to obtain mixture A, co-dissolving the easily soluble cobalt salt and ammonium niobium oxalate in 10% aqueous hydrochloric acid solution, heating to 50 degrees C, adding sorbic acid under high-speed stirring to keep the solution clear, cooling to room temperature, allowing to stand for 6-8 hours, then heating to 60 degrees C, continuously adding sorbic acid under high-speed stirring, keeping the solution clear, stirring the solution at 85-90 degrees C to evaporate 1/2 of the water, cooling to room temperature to obtain a gel, drying the gel for 2 hours, sufficient grinding, heating up in a box-type resistance furnace at a rate of not greater than 3 degrees C per minute to 200-250 degrees C for 5 hours, continuously heating to 300-350 degrees C at a rate of not greater than 3 degrees C per minute for 3 hours, naturally cooling to room temperature to obtain a mixture B, under continuous stirring, adding chloroplatinic acid to 20-25 wt.% glucose aqueous solution, stirring at constant temperature at 30-35 degrees C until clear, adding mixture A, heating to 50 degrees C, stirring at constant temperature for 3-4 hours, adding the mixture B, stirring at constant temperature for 4-5 hours, naturally cooling to room temperature, filtering, washing the filter cake with deionized water for 3 times, drying in a vacuum oven at 60 degrees C to obtain a graphene-supported platinum atom doped mixture A composite powder material composed of cobalt monoxide and niobium pentoxide.