Acetone sensing applications of Ag modified TiO2 porous nanoparticles synthesized via facile hydrothermal method

Abstract

Titanium dioxide, owing to its manifold characteristics, specifically excellent sensitivity and stability under harsh environment, is considered as one of the probable replacements for VOCs gas sensing applications. The response of TiO2 is significantly influenced by its porosity and metal doping. To this context, this report demonstrates a facile one-pot hydrothermal method to synthesize porous TiO2 nanoparticles (NPs) modified with sliver (1–5 mol%). The gas sensing performance of the sensors was investigated by testing their gas response to acetone, which is proved of highly effective for sensor applications. For instance, the sensor based on 2 mol % Ag-TiO2 showed high response (SR ~ 13.9), fast response (11 s) and recovery (14 s) time, good long-term stability (30 days) and good selectivity (SF ~ 12.6) toward 100 ppm acetone against other VOCs. To understand and authenticate the sensing mechanism, the structure and morphology of synthesized NPs was performed by XRD, XPS, SEM, EDS, TEM and HRTEM. Furthermore, a plausible sensing mechanism is discussed on basis of the obtained results.