Synthesis and gas sensor application of nanostructure Cr₂O₃ hollow spheres

This paper prepared single phase Cr₂O₃ hollow spheres by the template method. The templates was carbon spheres prepared by glucose hydro-thermal method. The Cr₂O₃ hollow spheres were confirmed and characterized by TEM and N₂ adsorption-desorption. Then we investigated the gas sensor application of nanostructure Cr₂O₃ hollow spheres. The gas sensor properties of the Cr₂O₃ hollow spheres to some toxic flammable gases were investigated by resistance response method. The result showed that the sensor was extremely sensitive to the temperature, the resistance of sensor was increased linearly with the concentration of reductive gases varies from 50 to 250 ppm at optimum operating temperature (300°C). The response and recovery of the sensor was fast with the time to reach 70% of the total resistance change was 16 s and 7 s. (paper)