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

Abstract

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 °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.