Detection of Flammable and Toxic Analytes by Urchin-like ZnO Nanomaterials

This contribution focuses on ZnO-based gas sensors with outstanding performances in the detection of flammable and toxic analytes, including acetone, ethanol, hydrogen, nitrogen dioxide, ozone and carbon monoxide. In particular, ZnO nanorods (NRs) were grown by Plasma-Assisted Chemical Vapor Deposition (PA-CVD) on polycrystalline Al2O3 slides at 200-300°C. The system characterization by Glancing incidence X-ray diffraction (GIXRD) and Field Emission Scanning Electron Microscopy (FESEM) evidenced the formation of <001> oriented NR arrays with a unique urchin-like morphology. The obtained nanosystems were tested as solid state gas sensors, providing very high responses, a significant reversibility and appreciably low detection limits.