Electrospun polyvinyl acetate nanofiber modified quartz crystal microbalance for detection of primary alcohol vapor

Analytical parameters including sensitivity in the QCM sensing system are critical to understand its sensing mechanism. We investigated the QCM analytical parameters after the QCM electrode surface was modified with polyvinyl acetate (PVAc) nanofiber for primary alcohols' vapor detection. The PVAc nanofibers were prepared by electrospinning method and were observed using a scanning electron microscope (SEM). The modified QCM sensing system was used to test the vapor of primary alcohols. The QCM sensitivity for methanol, ethanol, n-propanol, n-butanol, and n-pentanol was found to be 6.8 +/- 0.4, 13.1 +/- 0.5, 25.2 +/- 1.1, 39.7 +/- 1.9, and 51.9 +/- 2.6 Hz mg(-1) L, respectively. The limit of detection for npentanol vapor was 0.023 mg/L, which the highest of all. The shortest response time was 4s, when it was exposed to methanol vapor. The intermolecular interaction between the active surface and gaseous molecules is believed to responsible for frequency shift. The concentration of the analyte in the air is linearly correlated to the compound vapor pressure. The results could provide a new promising way to detect vapor of structurally similar of volatile organic compounds (VOCs) by QCM. (C) 2019 Elsevier B.V. All rights reserved.