SnO ₂ /NaA and ZnO/NaA nanocomposites: excellent low temperature ethylene glycol sensors

This study developed a low-temperature thick film sensor for detecting ethylene glycol (EG) using ZnO and SnO2 nanoparticles, along with their nanocomposites with NaA zeolite. The sensors were fabricated via screen printing and characterized using X-ray diffraction (XRD), Fourier-transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TG/DTA), scanning electron microscopy (SEM), and UV-visible spectroscopy. The sensors' response to EG was evaluated by measuring changes in dielectric constant, AC conductivity, and optical properties at EG concentrations as low as 2 ppm. SnO2-based sensors detected EG at 140°C, while ZnO sensors operated at 155°C. The addition of NaA zeolite reduced the operational temperature for SnO2-based sensors to 110°C and enhanced the sensitivity. The SnO2 (2 wt%)/NaA sensor exhibited the best performance. The results suggest that blending zeolites, particularly NaA, improves gas sensing properties, offering a promising approach for low-temperature EG detection and enhanced sensor performance.