Preparation of nanocrystalline stacked spherical SnO2 with higher specific surface area and its gas-sensing performance

In order to improve the sensitivity of SnO 2 to ethanol gas, the spherical SnO 2 with a particle size of 0.25μm and uniform particle distribution was prepared by hydrothermal method without adding surfactants. The characterizations were conducted，and the results showed that the spherical SnO 2 particles were stacked by fine grains with a grain size of 4nm, with a higher specific surface area of 232.2043m 2 /g than existing research results. The gas-sensing performance test results show that the spherical SnO 2 has the best gas-sensing selectivity to ethanol, with an optimal working temperature of 300℃. When the ethanol concentration is 100ppm, the gas sensitivity of spherical SnO 2 to ethanol is 48.28, with a response time of 4s and a recovery time of 15s. Even to low concentration ethanol of 2ppm, the sensitivity of the spherical SnO 2 can reach 4.6, indicating excellent gas-sensing performance of the spherical SnO 2 . This study provides data reference for the research and development of high-performance gas sensors.