Highly sensitive detection of volatile terpineol and butyl xanthate gases based on p-type semiconducting Co3O4 sensing nanomaterials with different morphologies synthesized by facile hydrothermal method

To effectively detect the volatile terpineol and butyl xanthate gases produced during the flotation process in mineral processing plants, Co 3 O 4 nanosheets, Co 3 O 4 nanoparticles, and Co 3 O 4 nanoflowers were synthesized via one-pot hydrothermal method as sensing materials. The crystal structure and microscopic morphology of the synthesized materials were characterized using XRD, SEM and TEM, respectively. The specific surface area and pore-size distribution were recorded using BET. The elemental distribution and valence states were analyzed using XPS, and the chemical bonds and functional groups were analyzed using FTIR. The gas sensing properties demonstrated that Co 3 O 4 nanosheets exhibited superior sensing performance over Co 3 O 4 nanoparticles and Co 3 O 4 nanoflowers. The Co 3 O 4 nanosheets showed maximum responses of 8.06 and 9.17 to 50 ppm volatile terpineol and 200 ppm volatile butyl xanthate gases at the optimal operating temperature of 200 °C, respectively, as well as favorable gas sensing response-recovery characteristics and reproducibility. The superior performance is attributed to the abundant oxygen vacancies and the distinctive porous structure of Co 3 O 4 nanosheets. This work significantly contributes to the development of high-performance gas sensors for the mining industry.