▎ 摘　　要

NOVELTY - Preparing tin oxide-reduced graphene oxide composite material involves dissolving 0.001-0.01 g graphene oxide in 20-50 ml ethanol solution ultrasonically disperse to obtain graphene oxide solution. 0.05-2.0 g tin (IV) chloride pentahydrate is dissolved in 20-50 ml deionized water under stirring magnetically, and then poured into graphene oxide solution under stirring for 5-30 minutes. The obtained mixed solution is transferred into the reaction kettle at 120-200 degrees C for 12-36 hours. The inner lining of the reactor under stirring and putting for centrifugation. The treated centrifuge tube is poured in distilled water and ethanol alternately to centrifuge and clean. The obtained precipitate is placed into an oven at 40-100 degrees C for 5-20 hours, and then taken out the powder sample to put the powder sample into the tube furnace under protective gas to calcine at 300-700 degrees C for 0.5-4 hours. The tube furnace is cooled to room temperature, and taken out the powder sample. USE - Method for preparing tin oxide-reduced graphene oxide (SnO2/rGO) composite material used in ultra-high-sensitivity ethanol sensor (claimed). ADVANTAGE - The method prepares the tin oxide-reduced graphene oxide composite material in a simple, cost-effective and eco-friendly manner with high sensitivity response. DETAILED DESCRIPTION - Preparing tin oxide-reduced graphene oxide composite material involves dissolving 0.001-0.01 g graphene oxide in 20-50 ml ethanol solution ultrasonically disperse to obtain graphene oxide solution. 0.05-2.0 g tin (IV) chloride pentahydrate is dissolved in 20-50 ml deionized water under stirring magnetically, and then poured into graphene oxide solution under stirring for 5-30 minutes. The obtained mixed solution is transferred into the reaction kettle at 120-200 degrees C for 12-36 hours. The inner lining of the reactor under stirring and putting for centrifugation. The treated centrifuge tube is poured in distilled water and ethanol alternately to centrifuge and clean. The obtained precipitate is placed into an oven at 40-100 degrees C for 5-20 hours, and then taken out the powder sample to put the powder sample into the tube furnace under protective gas to calcine at 300-700 degrees C for 0.5-4 hours. The tube furnace is cooled to room temperature, and taken out the powder sample. The muffle furnace is heated to 300-700 degrees C to form powder sample. The powder sample is taken out and naturally cooled to room temperature to obtain the tin oxide-reduced graphene oxide composite material. INDEPENDENT CLAIMS are included for the following: (1) an ultra-high sensitivity ethanol sensor, which comprises aluminum oxide ceramic tube covered with two parallel ring-shaped metal electrodes in circumferential direction; and (2) a method for manufacturing an ultra-high-sensitivity ethanol sensor, which involves taking 0.001-0.1 g tin oxide-reduced graphene oxide composite powder and 0.01-2 ml distilled water to grind into a uniform slurry, coating the slurry on the surface of the aluminum oxide ceramic tube, taking out the aluminum oxide ceramic tube after drying, passing the nickel-cadmium alloy heating coil through inside of the ceramic tube, finally connecting platinum wires at both ends of the ceramic tube and the nickel-cadmium alloy heating coil at both ends, aging manufactured sensor for 5-20 days in an air environment at 150-400 degrees C to obtain a stable performance ethanol gas sensor.