Gas sensors based on ultrathin porous Co3O4 nanosheets to detect acetone at low temperature

Using a facile two-step process, including a hydrothermal technique and subsequently controlled annealing of the precursor, ultrathin porous Co3O4 nanosheets can be synthesized. The gas sensor based on the porous Co3O4 nanosheets shows a superior acetone gas-sensing performance at a low operating temperature of 150 degrees C. The gas response to 100 ppm acetone reached 11.4, and exhibited good reproducibility. In addition, the detection limit of the Co3O4 nanosheet sensor is lower than 1.8 ppm, which is the diagnostic criteria exhaled from diabetes. What's more, the sensor exhibited good stability when tested over 2 months. The outstanding gas-sensing properties were explained by a typical p-type semiconductor behavior with an ultrathin porosity structure as well as a large specific surface area of Co3O4 nanosheets.