Synthesis and Fabrication of Y-Doped ZnO Nanoparticles and Their Application as a Gas Sensor for the Detection of Ammonia

Abstract

A facile co-precipitation technique is used in the synthesis of pure ZnO and Y-doped (5, 10 and 15 wt.%) ZnO nanostructures (YZO) and fabricated by using electron beam deposition over a glass substrate. The crystal morphological features of pure ZnO and YZO nanoparticles (NPs) were characterized by XRD (x-ray diffraction), CV (cyclic voltammetry), SEM (scanning electron microscopy), UV–visible spectroscopy and PL (photoluminescence) spectroscopic techniques. Drastic change in the crystalline phase and morphology is observed as a result of Y+3 doping. The polar surface area of Zn 2+ vanished due to charge compensation Y3+ which in turn responsible for transition in morphology of pure ZnO from hexagonal to spherical shape (YZO). In comparison with pure ZnO NPs, Y-doped ZnO exhibited better ammonia gas sensing properties. The selectivity and sensitivity of 150 ppm of ammonia gas at 250 °C for 15 wt.% of YZO were comparatively higher than pure ZnO nanostructures. The response and recovery time of 15 wt.% of YZO was 58 s and 87 s, respectively. The gas sensor YZO nanostructures exhibited better selectivity toward ammonia gas compared with the other volatile gases such as methane, hydrogen sulfide, ethylene, chloroform. The selectivity and sensor features of Y-doped ZnO were experimentally analyzed.