Novel Strategy to Prepare Mesoporous Sn-Doped Co3O4 Whiskers with High Sensitivity to Toluene

Tremendous attention has been devoted to the development of high-performance gas sensors for practical applications because of their importance for our health and safety. The distinctive Sn-doped Co3O4 whiskers have been successfully prepared via a novel strategy involving the preparation and sintering of salicylic anion-intercalated Sn-doped cobalt layered hydroxide whiskers. The Sn-doped Co3O4 whiskers have smaller crystal sizes, lower crystallinity, and higher specific surface area than pure Co3O4. Notably, the sensor based on 3 at. % Sn-doped Co3O4 whiskers showed the highest response of 53.8-50 ppm of toluene at 240 degrees C, which was 7.6 times higher than that of the sensor based on pure Co3O4. Moreover, the 3 at. % Sn-doped Co3O4 whisker-based sensor also possesses the advantages of high selectivity, excellent repeatability, remarkable long-term stability, and low detection limit, indicating that the 3 at. % Sn-doped Co3O4 whiskers are a hopeful sensing material for the detection of toluene gas.