An Enhanced Fast Ethanol Sensor Based on Zinc Oxide/Nickel Oxide Nanocomposite in Dynamic Situations

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An Enhanced Fast Ethanol Sensor Based on Zinc Oxide/Nickel Oxide Nanocomposite in Dynamic Situations Shaqayeq Teymoori Hezarjaribi1 · Shahruz Nasirian1  Received: 23 February 2020 / Accepted: 24 April 2020 © Springer Science+Business Media, LLC, part of Springer Nature 2020

Abstract  Measuring ethanol levels in dynamic conditions calls for smart fast response sensors. Herein we report, fabrication and characterization of a Zinc oxide/Nickel oxide nanocomposite (ZN) for use as an ethanol gas (ET) sensor. Based on XRD, FESEM, and BET measurements, it is found that the formed ZN has a novel nano-worm morphology, and the specific surface area about 19.5 m ­ 2 ­gm−1. The ET sensing results of the ZN sensor (ZNS) toward 0.025 vol% ET demonstrated an appropriate response value of 32.48% with a less response/recovery time of 2.7/3.6 s at room temperature. Moreover, the effect of various humidity levels on the sensor response as a function of gas concentration investigated. Our handmade sensor revealed not only long-term stability over four months with a small degradation of 9%, but also the excellent selectivity toward the ET than other gases. Finally, the ET sensing mechanism of the ZNS discussed, as well. Graphic Abstract

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Keywords  Zinc oxide/nickel oxide nanocomposite · Gas sensor · Ethanol gas · Dynamic situations · Room temperature

1 Introduction

* Shahruz Nasirian [email protected]; [email protected] 1



Department of Electrical and Medical Engineering, Mazandaran University of Science and Technology, Sardaran 12 Avenue, Sheikh Tabarsi Street, P.O. Box 734, Babol, Iran

Recently, novel nanostructures of binary semiconductor metal oxides with tunable physical and chemical nature considered for development of smart gas sensors [1–9]. One of the superior semiconductor metal oxides (SMOs) with 3.37 eV bandgap, high electron mobility, stability, excellent thermal and chemical features [4, 10],

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non-toxicity, easy preparation [11], and sensitivity to various gases such as volatile organic compounds (VOCs) is n-type zinc oxide (ZnO) [2, 12]. Although ZnO is a suitable candidate for the use in the VOCs gas sensors, the main drawback associated with it is unsatisfied sensitivity, decay response and high operating temperatures (100–450 °C) [3, 13]. The composite of the ZnO with metal ions [14–17], polymers [3, 9] and other SMOs [13, 18–20] has been suggested to overcome mentioned problems. Herein, a novel nanocomposite based on n-type ZnO and a p-type SMO is an excellent strategy to achieve this goal, because it has advantages of both SMOs [14, 21, 22]. P-type nickel oxide (NiO) with superior gas sensing features such as high oxygen/hydroxyl adsorption and low operating temperature toward VOC