Branch-like NiO/ZnO heterostructures for VOC sensing
Authors: Kaur N., Zappa D., Ferroni M., Poli N., Campanini M., Negrea R., Comini E.
Autors Affiliation: [Kaur, Navpreet; Zappa, Dario; Ferroni, Matteo; Poli, Nicola; Comini, Elisabetta] Univ Brescia, SENSOR Lab, Via D Valotti 9, I-25133 Brescia, Italy and CNR, INO, Via D Valotti 9, I-25133 Brescia, Italy.
[Campanini, Marco] EMPA, Electron Microscopy Ctr, Uberlandstr 129, CH-8600 Zurich, Switzerland.
[Negrea, Raluca] Natl Inst Mat Phys, Atomistilor St 105 Bis,POB Mg 7, R-077125 Bucharest, Romania.
Abstract: We report for the first time on the synthesis of NiO/ZnO one-dimensional (1D) nanowire (NW) based heterostructures by applying a suitable methodology of transport and condensation. The synthesis involves, firstly the growth of NiO NWs on gold (Au) catalyzed alumina substrates using the vapor-liquid-solid (VLS) mechanism and then the formation of ZnO NWs directly on the NiO NWs using the vapor-solid (VS) mechanism. Sequential evaporation-condensation over Au-seeded alumina promotes the formation of NiO NWs, driven by the VLS growth mechanism. These NiO NWs act as backbones for the condensation of epitaxial ZnO nanostructures. The detailed morphological study of these heterostructures reveals that ZnO nanowires completely cover the whole NiO nanowires completely and growing out in the form of flat leaves from the NiO nanowire branches. The diameters of the NiO NWs have been found to vary from 15 nm to 60 nm. Selected area electron diffraction data (SAED) indicate an epitaxial growth of ZnO nanowires along (101)-planes on the strongly oriented NiO nanowires along (200) crystallographic planes. Finally, NiO NW and NiO/ZnO heterostructure based conductometric gas sensing devices have been fabricated and the comparison between their sensing performances have been compared. Interestingly, NiO/ZnO NWs heterostructure based sensing devices shows superior performance compared to NiO sensors toward volatile organic compounds (VOC). (C) 2018 Elsevier B.V. All rights reserved.
Journal/Review: SENSORS AND ACTUATORS. B, CHEMICAL (PRINT)
Volume: 262 Pages from: 477 to: 485
KeyWords: Nickel oxide; Zinc oxide; Electron microscopy; Gas sensing; HeterostructuresDOI: 10.1016/j.snb.2018.02.042Citations: 24data from “WEB OF SCIENCE” (of Thomson Reuters) are update at: 2019-10-20References taken from IsiWeb of Knowledge: (subscribers only)Connecting to view paper tab on IsiWeb: Click hereConnecting to view citations from IsiWeb: Click here