Highly sensitive and ultrafast response surface acoustic wave humidity sensor based on electrospun polyaniline/poly(vinyl butyral) nanofibers

• Published in: Analytica chimica acta Vol. 748; pp. 73 - 80
• Main Authors: Lin, Qianqian, Li, Yang, Yang, Mujie
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 20.10.2012; Elsevier
• Subjects: Analytical chemistry; Chemistry; Composite nanofibers; Detection; Electrospinning; Exact sciences and technology; General, instrumentation; Humidity; Humidity sensor; Linearity; Nanofibers; Polyaniline; Polyanilines; Sensors; Surface acoustic wave; Surface acoustic waves; Humidity sensor; Electrospinning; Surface acoustic wave; Polyaniline; Composite nanofibers; Performance evaluation; Surface acoustic wave sensors; Acoustic wave; Nanofiber; Humidity; Response surface; Aniline polymer; Scanning electron microscopy; Desiccation; Surface wave; Fluorides oxides; Polymer; Chemical sensor; Electron microscopy; Sensitivity; Response time; Linearity; Morphology; Frequency; Ethylene oxide; Detection; Methyl methacrylate; Room temperature
• ISSN: 0003-2670; 1873-4324
• DOI: 10.1016/j.aca.2012.08.041

[Display omitted] ► Polyanline/poly(vinyl butyral) nanofibers are prepared by electrospinning. ► Nanofiber-based SAW humidity sensor show high sensitivity and ultrafast response. ► The SAW sensor can detect very low humidity. Polyaniline (PANi) composite nanofibers were deposited on surface acoustic wave (SAW) resonator with a central frequency of 433MHz to construct humidity sensors. Electrospun nanofibers of poly(methyl methacrylate), poly(vinyl pyrrolidone), poly(ethylene oxide), poly(vinylidene fluoride), poly(vinyl butyral) (PVB) were characterized by scanning electron microscopy, and humidity response of corresponding SAW humidity sensors were investigated. The results indicated that PVB was suitable as a matrix to form nanofibers with PANi by electrospinning (ES). Electrospun PANi/PVB nanofibers exhibited a core–sheath structure as revealed by transmittance electron microscopy. Effects of ES collection time on humidity response of SAW sensor based on PANi/PVB nanofibers were examined at room temperature. The composite nanofiber sensor exhibited very high sensitivity of ∼75kHz/%RH from 20 to 90%RH, ultrafast response (1s and 2s for humidification and desiccation, respectively) and good sensing linearity. Furthermore, the sensor could detect humidity as low as 0.5%RH, suggesting its potentials for low humidity detection. Attempts were done to explain the attractive humidity sensing performance of the sensor by considering conductivity, hydrophilicity, viscoelasticity and morphology of the polymer composite nanofibers.