title: SAW Humidity Sensor Sensitivity Enhancement via Electrospraying of Silver Nanowires.
abstract: In this research, we investigated the influence of the surface coatings of silver nanowires on the sensitivity of surface acoustic wave (SAW) humidity sensors. Silver nanowires, with poly(vinylpyrrolidone) (PVP), which is a hydrophilic capping agent, were chemically synthesized, with an average length of 15 µm and an average diameter of 60 nm. Humidity sensors, with 433 MHz frequency dual-port resonator Rayleigh-SAW devices, were coated by silver nanowires (AgNWs) using the electrospray coating method. It was demonstrated that increasing thickness of coated AgNW on the surfaces of SAW devices results in increased sensitivity. The highest frequency shift (262 kHz) in these SAW devices was obtained with an injection of 0.5 mL of the AgNW solution with a concentration of 0.5 mg/mL at an injection rate of 1 mL/h. It also showed the highest humidity sensitivity among the other prepared SAW devices.
authors.affiliation: Istanbul Sehir University, Department of Industrial Engineering, Altunizade Mh., Kusbakisi Cad., No. 27, Uskudar-Istanbul 34662, Turkey. faridirani@std.sehir.edu.tr.
authors.forename: Farid
authors.initials: F
authors.lastname: Sayar Irani
authors.affiliation: Istanbul Sehir University, Department of Industrial Engineering, Altunizade Mh., Kusbakisi Cad., No. 27, Uskudar-Istanbul 34662, Turkey. bahadir.tunaboylu@tubitak.gov.tr.|Tubitak Marmara Research Center, PK 21, Gebze, Kocaeli 41470, Turkey. bahadir.tunaboylu@tubitak.gov.tr.
authors.forename: Bahadir
authors.initials: B
authors.lastname: Tunaboylu
keywords: electrospray; humidity sensor; silver nanowire; surface acoustic wave (SAW) sensor