Enhanced acetone sensing properties of titanium dioxide nanoparticles with a sub-ppm detection limit

In the present study, a simple hydrothermal approach has been successfully applied for a large scale synthesis of anatase titanium dioxide nanoparticles (TiO₂ NPs) using titanium glycolate precursors and is utilized for the fabrication of low-cost high performance acetone (CH₃COCH₃) gas sensors after corroborating the crystallinity, phase-purity, and surface morphology investigations. Several randomly distributed TiO₂ aggregates, composed of NPs, are noticed from morphology analysis. Chemiresistive properties of as-fabricated TiO₂ sensors attempted towards host of oxidizing and reducing gases, reveal a superior selectivity to CH₃COCH₃ with a maximum response of 15.24 (1000 ppm) @270 °C compared to other target gases. One of the key features of as-fabricated TiO₂ sensor is the lowest detection limit of 500 ppb to CH₃COCH₃ with rapid response and recovery times, signifying commercial potential of the developed sensor materials. The effect of operating temperature along with various concentrations of CH₃COCH₃ on the gas sensing properties of TiO₂ sensor has thoroughly been investigated and reported. Finally, the interaction mechanism between the CH₃COCH₃ molecules and the TiO₂ NPs sensor was elaborated in depth for a thorough understanding sensor performance experimentally and supposedly.