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

This contribution focuses on ZnO-based gas sensors with outstanding performances in the detectionof flammable and toxic analytes, including acetone, ethanol, hydrogen, nitrogen dioxide, ozone andcarbon monoxide. In particular, ZnO nanorods (NRs) were grown by Plasma-Assisted Chemical VaporDeposition (PA-CVD) on polycrystalline Al2O3 slides at 200-300°C. The system characterization byGlancing 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. Theobtained nanosystems were tested as solid state gas sensors, providing very high responses, asignificant reversibility and appreciably low detection limits.