title: A surface acoustic wave humidity sensor with high sensitivity based on electrospun MWCNT/Nafion nanofiber films.
abstract: Humidity detection has been widely used in a variety of fields. A humidity sensor with high sensitivity is reported in this paper. A surface acoustic wave resonator (SAWR) with high resonance frequency was fabricated as a basic sensitive component. Various nanotechnologies were used to improve the sensor's performance. A multi-walled carbon nanotube/Nafion (MWCNT/Nafion) composite material was prepared as humidity-sensitive films, deposited on the surface of an SAWR by the electrospinning method. The electrospun MWCNT/Nafion nanofiber films showed a three-dimensional (3D) porous structure, which was profitable for improving the sensor's performance. The new nano-water-channel model of Nafion was also applied in the humidity sensing process. Compared to other research, the present sensor showed excellent sensitivity (above 400 kHz/% relative humidity (RH) in the range from 10% RH to 80% RH), good linearity (R(2) > 0.98) and a short response time (∼3 s@63%).
authors.affiliation: Department of Biomedical Engineering, Zhejiang University, Hangzhou, People's Republic of China. thunder@zju.edu.cn
authors.forename: Lei
authors.initials: L
authors.lastname: Sheng
authors.forename: Chen
authors.initials: C
authors.lastname: Dajing
authors.forename: Chen
authors.initials: C
authors.lastname: Yuquan
mesh_terms: D000162:Acoustics; D005465:Fluorocarbon Polymers / Q000737:chemistry*; D006813:Humidity; D057139:Nanofibers / Q000737:chemistry* / Q000648:ultrastructure; D036103:Nanotechnology / Q000295:instrumentation* / Q000379:methods*; D037742:Nanotubes, Carbon / Q000737:chemistry* / Q000648:ultrastructure; D015203:Reproducibility of Results; D013499:Surface Properties; D013696:Temperature
chemical_list: D005465:Fluorocarbon Polymers; D037742:Nanotubes, Carbon; C040402:perfluorosulfonic acid