Mesoporous Sno2 Nanospheres Sensor for Fast Detection of Hcho and its Application in Safety Detection of Aquatic Products

SnO2 nanospheres assembled by nanoparticles were synthesized without any template or surfactant by straightforward solvothermal method. The mesoporous SnO2 nanomaterial is obtained with high specific surface area (122.54 m2·g−1) after calcination at high temperature. The excellent gas sensing properties of such SnO2 nanospheres at the lower operating temperature of 133 °C include the high response (36.5) to 100 ppm formaldehyde and the ability to respond quickly within 6 s. In the current reports, such short response time has obvious advantage. The SnO2 sensor has also a large linear response from 0.01 ppm to 100 ppm. Meanwhile, the gas sensor also has excellent selectivity, humidity resistance and long-term stability. XPS and GC-MS technology were applied to detect the change of element state on SnO2 surface and composition of gaseous products after reacting with formaldehyde for purpose of investigate the response mechanism of SnO2 nanospheres to formaldehyde. Meanwhile, the formaldehyde sensing mechanism of SnO2 is discussed in depth. Furthermore, the practical application test was also carried out after the aquatic products were soaked in the formaldehyde solution.