Room-Temperature Ammonia Sensor Based on ZnO Nanorods Deposited on ST-Cut Quartz Surface Acoustic Wave Devices

Wei Li; Yuanjun Guo; Yongliang Tang; Xiaotao Zu; Jinyi Ma; Lu Wang; Yong Qing Fu

doi:10.3390/s17051142

Room-Temperature Ammonia Sensor Based on ZnO Nanorods Deposited on ST-Cut Quartz Surface Acoustic Wave Devices

Sensors (Basel). 2017 May 17;17(5):1142. doi: 10.3390/s17051142.

Authors

Wei Li¹, Yuanjun Guo², Yongliang Tang³, Xiaotao Zu⁴, Jinyi Ma⁵, Lu Wang⁶, Yong Qing Fu^{7

8}

Affiliations

¹ School of Physical Electronics, University of Electronic Science and Technology of China, Chengdu 610054, China. 201421040126@std.uestc.edu.cn.
² School of Physical Electronics, University of Electronic Science and Technology of China, Chengdu 610054, China. yuanjun_guo@hotmail.com.
³ School of Physical Electronics, University of Electronic Science and Technology of China, Chengdu 610054, China. 201311040302@std.uestc.edu.cn.
⁴ School of Physical Electronics, University of Electronic Science and Technology of China, Chengdu 610054, China. xtzu@uestc.edu.cn.
⁵ Sichuan Institute of Piezoelectric and Acousto-Optic Technology, Chongqing 400060, China. ma_jinyi163@163.com.
⁶ Sichuan Institute of Piezoelectric and Acousto-Optic Technology, Chongqing 400060, China. wanglu720@163.com.
⁷ School of Physical Electronics, University of Electronic Science and Technology of China, Chengdu 610054, China. richard.fu@northumbria.ac.uk.
⁸ Faculty of Engineering & Environment, University of Northumbria, Newcastle upon Tyne NE1 8ST, UK. richard.fu@northumbria.ac.uk.

Abstract

Using a seed layer-free hydrothermal method, ZnO nanorods (NRs) were deposited on ST-cut quartz surface acoustic wave (SAW) devices for ammonia sensing at room temperature. For a comparison, a ZnO film layer with a thickness of 30 nm was also coated onto an ST-cut quartz SAW device using a sol-gel and spin-coating technique. The ammonia sensing results showed that the sensitivity, repeatability and stability of the ZnO NR-coated SAW device were superior to those of the ZnO film-coated SAW device due to the large surface-to-volume ratio of the ZnO NRs.

Keywords: NH3 sensor; ZnO nanorods; seed layer-free growth; surface acoustic wave (SAW) device.