Nanostructured cobalt antimonate: a fast responsive and highly stable sensing material for liquefied petroleum gas...

Herein, cobalt antimonate (CoSb₂O₆) nanospheres were fabricated via the sol-gel spin-coating process and employed as a functional liquefied petroleum gas (LPG) sensor at room temperature (25 °C). The microstructure of the fabricated CoSb₂O₆ thin films (thickness ∼ 250 nm) was analyzed via scanning electron microscopy, which revealed the growth of nanospheres having an average diameter of ∼45 nm. The XRD analysis demonstrated the crystalline nature of CoSb₂O₆ with a crystallite size of ∼27 nm. Finally, the fabricated thin films were investigated as sensors for LPG and carbon dioxide (CO₂) at room temperature (25 °C) and 55% R.H. (relative humidity) with different concentrations in the range of 1000-5000 ppm. The sensing results demonstrated greater variations in the electrical properties of films for the incoming LPG than that of the CO₂ gas adsorption. Furthermore, to ensure the long-term stability of fabricated sensors, they were tested periodically at 10 days interval, spanning a total duration of 60 days. In summary, our fabricated LPG sensor displayed high sensitivity (1.96), repeatability, quick response time (21 s) and high long-term stability (99%). Therefore, CoSb₂O₆ nanospheres can be functionalized as a potential LPG-sensitive material characterized by high sensitivity, reliability and stability at room temperature.