Facile synthesis of Cr-decorated hexagonal Co₃O₄ nanosheets for ultrasensitive ethanol detection
Pingping Zhang1, Jiwei Wang, Xiaoxin Lv
1Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices, Institute of Functional Nano and Soft Materials (FUNSOM), Soochow University, Suzhou, Jiangsu 215123, People's Republic of China.
Abstract:
Cr-decorated hexagonal Co3O4 nanosheets were synthesized by a facile hydrothermal method on a SiO2/Si substrate, followed by a simple physical deposition of Cr film and a thermal annealing treatment. The Co3O4 nanosheets possess a porous and polycrystalline structure consisting of Co3O4 nanoparticles; Cr2O3 nanoparticles are uniformly formed on the surface of the Co3O4 nanosheets after the annealing treatment. The ethanol-sensing properties of the Cr-decorated hexagonal Co3O4 nanosheets were investigated in detail, and compared to pure hexagonal Co3O4 nanosheets, they show unique sensing properties toward ethanol, including high response (5.4) even when the ethanol concentration is as low as 10 ppm, ultrafast response (1 s) and recovery (7 s) rates, and good selectivity at a 300 °C operating temperature. These properties make the Cr-decorated hexagonal Co3O4 nanosheets good candidates for ethanol detection.
