A Simple Graphene NH₃ Gas Sensor via Laser Direct Writing

Dezhi Wu; Qianqian Peng; Shan Wu; Guangshun Wang; Lei Deng; Huiling Tai; Lingyun Wang; Yajie Yang; Linxi Dong; Yang Zhao; Jinbao Zhao; Daoheng Sun; Liwei Lin

doi:10.3390/s18124405

A Simple Graphene NH₃ Gas Sensor via Laser Direct Writing

Sensors (Basel). 2018 Dec 13;18(12):4405. doi: 10.3390/s18124405.

Authors

Dezhi Wu¹, Qianqian Peng², Shan Wu³, Guangshun Wang⁴, Lei Deng⁵, Huiling Tai⁶, Lingyun Wang⁷, Yajie Yang⁸, Linxi Dong⁹, Yang Zhao¹⁰, Jinbao Zhao¹¹, Daoheng Sun¹², Liwei Lin^{13

14}

Affiliations

¹ Department of Mechanical and Electrical Engineering, Xiamen University, Xiamen 361005, China. wdz@xmu.edu.cn.
² Department of Mechanical and Electrical Engineering, Xiamen University, Xiamen 361005, China. qianp77@stu.xmu.edu.cn.
³ Department of Mechanical and Electrical Engineering, Xiamen University, Xiamen 361005, China. 34520162201412@stu.xmu.edu.cn.
⁴ Department of Mechanical and Electrical Engineering, Xiamen University, Xiamen 361005, China. wanggs@stu.xmu.edu.cn.
⁵ Department of Mechanical and Electrical Engineering, Xiamen University, Xiamen 361005, China. 32020151153660@stu.xmu.edu.cn.
⁶ State Key Laboratory of Electronic Thin Films and Integrated Devices, University of Electronic Science and Technology of China, Chengdu 610054, China. taitai1980@uestc.edu.cn.
⁷ Department of Mechanical and Electrical Engineering, Xiamen University, Xiamen 361005, China. wangly@xmu.edu.cn.
⁸ State Key Laboratory of Electronic Thin Films and Integrated Devices, University of Electronic Science and Technology of China, Chengdu 610054, China. yangyajie@uestc.edu.cn.
⁹ Key Laboratory of RF Circuits and System of Ministry of Education, Hangzhou Dianzi University, Hangzhou 310018, China. donglinxi@hdu.edu.cn.
¹⁰ Department of Mechanical and Electrical Engineering, Xiamen University, Xiamen 361005, China. zhaoy@xmu.edu.cn.
¹¹ Department of Chemical Engineering, Xiamen University, Xiamen 361005, China. jbzhao@xmu.edu.cn.
¹² Department of Mechanical and Electrical Engineering, Xiamen University, Xiamen 361005, China. sundh@xmu.edu.cn.
¹³ Department of Mechanical and Electrical Engineering, Xiamen University, Xiamen 361005, China. lwlin@berkeley.edu.
¹⁴ Department of Mechanical Engineering, University of California at Berkeley, CA 94703, USA. lwlin@berkeley.edu.

Abstract

Ammonia gas sensors are very essential in many industries and everyday life. However, their complicated fabrication process, severe environmental fabrication requirements and desorption of residual ammonia molecules result in high cost and hinder their market acceptance. Here, laser direct writing is used to fabricate three parallel porous 3D graphene lines on a polyimide (PI) tape to simply construct an ammonia gas sensor. The middle one works as an ammonia sensing element and the other two on both sides work as heaters to improve the desorption performance of the sensing element to ammonia gas molecules. The graphene lines were characterized by scanning electron microscopy and Raman spectroscopy. The response and recovery time of the sensor without heating are 214 s and 222 s with a sensitivity of 0.087% ppm^-1 for sensing 75 ppm ammonia gas, respectively. The experimental results prove that under the optimized heating temperature of about 70 °C the heaters successfully help implement complete desorption of residual NH₃ showing a good sensitivity and cyclic stability.

Keywords: ammonia gas sensor; graphene; laser direct writing.