LAUSR

Abstract In this study, formaldehyde (FA) adsorption was performed by measuring the frequency change in quartz crystal microbalance (QCM) sensor, which coated with CuO-ZnO composite nanofibers by electrospinning method. The Zn(CH3COO)2 and Cu(CH3COO)2 with different molar ratios were added to the polyvinyl alcohol (PVA) polymer solution for electrospinning procedure and deposited on the surface of the QCM electrode. The QCM electrode was calcined at 350 °C for 5 h, then the CuO/ZnO composite nanofibers were characterized by Field Emission Scanning Electron Microscopes (FE-SEM), Fourier-Transform Infrared Spectroscopy (FTIR), Brunauer–Emmett–Teller (BET), and X-Ray Powder Diffraction (XRD), then formaldehyde adsorption properties were determined by using QCM sensors. When the increasing amount of FA is added to a closed system with a CuO/ZnO composite nanofiber coated QCM sensor, the resonance frequency was decreased. CuO/ZnO composite nanofibers with high surface area showed high adsorption capacity of FA even in the presence of intervening gases. The detection limit was found as 41 ppb, at room temperature. Also, to determine the homogeneity of CuO/ZnO composite nanofibers, the adsorption models were applied to adsorption data by using Scatchard, Langmuir, Freundlich, and Langmuir-Freundlich adsorption isotherms. The adsorption behavior of FA on CuO/ZnO composite nanofiber coated sensors was found as fitted with the Freundlich model.