Sensitive and Selective NH₃ Monitoring at Room Temperature Using ZnO Ceramic Nanofibers Decorated with Poly(styrene sulfonate)

Rafaela S Andre; Dongwook Kwak; Qiuchen Dong; Wei Zhong; Daniel S Correa; Luiz H C Mattoso; Yu Lei

doi:10.3390/s18041058

Sensitive and Selective NH₃ Monitoring at Room Temperature Using ZnO Ceramic Nanofibers Decorated with Poly(styrene sulfonate)

Sensors (Basel). 2018 Apr 1;18(4):1058. doi: 10.3390/s18041058.

Authors

Rafaela S Andre^{1

2

3}, Dongwook Kwak⁴, Qiuchen Dong⁵, Wei Zhong⁶, Daniel S Correa^{7

8}, Luiz H C Mattoso^{9

10}, Yu Lei¹¹

Affiliations

¹ Department of Chemical and Biomolecular Engineering, University of Connecticut, 191 Auditorium Road, Storrs, CT 06269, USA. lela_rsa@hotmail.com.
² Nanotechnology National Laboratory for Agriculture (LNNA), Embrapa Instrumentação, São Carlos 13560-970, SP, Brazil. lela_rsa@hotmail.com.
³ PPGQ, Department of Chemistry, Center for Exact Sciences and Technology, Federal University of São Carlos (UFSCar), São Carlos 13565-905, SP, Brazil. lela_rsa@hotmail.com.
⁴ Department of Materials Science and Engineering, University of Connecticut, 97 North Eagleville Road, Storrs, CT 06269, USA. dongwook.kwak@uconn.edu.
⁵ Department of Biomedical Engineering, University of Connecticut, 260 Glenbrook Road, Storrs, CT 06269, USA. qiuchen.dong@uconn.edu.
⁶ Department of Chemistry, University of Connecticut, 55 North Eagleville Road, Storrs, CT 06269, USA. wei.zhong@uconn.edu.
⁷ Nanotechnology National Laboratory for Agriculture (LNNA), Embrapa Instrumentação, São Carlos 13560-970, SP, Brazil. daniel.correa@embrapa.br.
⁸ PPGQ, Department of Chemistry, Center for Exact Sciences and Technology, Federal University of São Carlos (UFSCar), São Carlos 13565-905, SP, Brazil. daniel.correa@embrapa.br.
⁹ Nanotechnology National Laboratory for Agriculture (LNNA), Embrapa Instrumentação, São Carlos 13560-970, SP, Brazil. luiz.mattoso@embrapa.br.
¹⁰ PPGQ, Department of Chemistry, Center for Exact Sciences and Technology, Federal University of São Carlos (UFSCar), São Carlos 13565-905, SP, Brazil. luiz.mattoso@embrapa.br.
¹¹ Department of Chemical and Biomolecular Engineering, University of Connecticut, 191 Auditorium Road, Storrs, CT 06269, USA. yu.lei@uconn.edu.

Abstract

Ammonia (NH₃) gas is a prominent air pollutant that is frequently found in industrial and livestock production environments. Due to the importance in controlling pollution and protecting public health, the development of new platforms for sensing NH₃ at room temperature has attracted great attention. In this study, a sensitive NH₃ gas device with enhanced selectivity is developed based on zinc oxide nanofibers (ZnO NFs) decorated with poly(styrene sulfonate) (PSS) and operated at room temperature. ZnO NFs were prepared by electrospinning followed by calcination at 500 °C for 3 h. The electrospun ZnO NFs are characterized to evaluate the properties of the as-prepared sensing materials. The loading of PSS to prepare ZnO NFs/PSS composite is also optimized based on the best sensing performance. Under the optimal composition, ZnO NFs/PSS displays rapid, reversible, and sensitive response upon NH₃ exposure at room temperature. The device shows a dynamic linear range up to 100 ppm and a limit of detection of 3.22 ppm and enhanced selectivity toward NH₃ in synthetic air, against NO₂ and CO, compared to pure ZnO NFs. Additionally, a sensing mechanism is proposed to illustrate the sensing performance using ZnO NFs/PSS composite. Therefore, this study provides a simple methodology to design a sensitive platform for NH₃ monitoring at room temperature.

Keywords: NH3 sensor; PSS; ZnO NFs; good sensitivity; room temperature sensing.