Nano-architecture of highly sensitive SnO2-based gas sensors for acetone and ammonia using molecular imprinting technique

This article presents the nano-architecturing of highly sensitive SnO2-based gas sensors prepared by molecular imprinting technique with the presence of acetone and/or ammonia solvents to develop a sensor that has the ability to detect both gases which is being developed for the first time. Nanoparticles are prepared via hydrothermal method and then they have been characterized by field emission scanning electron microscope (FESEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and N-2 adsorption-desorption analyzer (BET) to determine their morphology, crystal structure, optical properties and surface area properties respectively. Four SnO2 films are fabricated using spin coating under different conditions of introducing ammonium hydroxide or acetone during the hydrothermal synthesis. Regular microsheets of about 5 mu m in length and 500 nm thickness have been built up from nanoparticles of sizes ranged from 20 to 50 nm depending on the preparation conditions. The sensing properties of the fabricated sensors are tested against (ammonium hydroxide, acetone, LPG, oxygen and benzene), where the results showed that when the participation of the solvent during the synthesis process, it increases the response for these gaseous. The performance of the gas sensor devices is demonstrated and got higher values (about 90%) for Ammonia gas when the device is template with ammonium hydroxide and water and washed with water (S-D) and limit of detection (600 ppb). Also, high sensitivity (about 77%) for Acetone is recorded for the device is template with ammonium hydroxide and acetone and washed with acetone (S-A) and limit of detection (280 ppb).