Abstract
As an ultra-sensitivity sensor, a quartz crystal microbalance (QCM) could be used to quantitatively characterize the relation between QCM parameters and the characteristics of viscoelastic films. When a QCM coated with a viscoelastic thin film is in the gas phase, based on the constructive equation of the quartz crystal and ignoring the capacitance effect, the equivalent Butterworth–Van Dyke (BVD) model of the QCM and the explicit expression for its frequency shift are derived. The “extra mass effect” deduced by the complex modulus is also obtained. It is found that the tendency of the BVD model in this work agrees well with that of Voinova’s model, although both are derived in different ways. Meanwhile, it can be seen that the two above-mentioned models exhibit different characteristics when compared with Sauerbrey’s model and Arnau’s model. The BVD model will help analyze the properties of viscoelastic films in the gas phase.
Highlights
A quartz crystal microbalance (QCM) is an ultra-sensitivity sensing device
In this work, based on Reed’s work and ignoring the capacitance effect, the equivalent Butterworth–Van Dyke (BVD) model of a QCM and the explicit expression for its frequency shift are derived, which can be applied in data analysis when the QCM is used for the characterization of viscoelastic films in the gas phase
When a QCM is coated with a viscoelastic film in the gas phase, according to Eq (5) and ignoring the capacitance effect, one can obtain the equivalent BVD model
Summary
A quartz crystal microbalance (QCM) is an ultra-sensitivity sensing device. It was originally used as a micro-quality detection device to detect the mass change in the nanogram scale.1 In 1959, Sauerbrey derived the relation between the frequency shift of the QCM and the mass change on its surface.2 In the 1980s, Nomura demonstrated that the QCM could work normally in liquid.3 When one side of a QCM is in contact with Newtonian liquid, the frequency shift of the QCM depends on the product of the density and the viscosity of the liquid, as derived by Kanazawa in 1985.4 Later, researchers found that the QCM has unique advantages and great applications in chemical, biological, and medical fields to realize high precision measurement.5–13 Researchers such as Reed extended it further to the characteristic analysis of viscoelastic films.14 Ornella developed a cost-effective immunosensor based on a QCM, which has promising potential in the field of cell biology.15 Mujahid discussed the application of a QCM in biosensing.16 Hussain studied the copolymer thin film on the QCM.17. In this work, based on Reed’s work and ignoring the capacitance effect, the equivalent BVD model of a QCM and the explicit expression for its frequency shift are derived, which can be applied in data analysis when the QCM is used for the characterization of viscoelastic films in the gas phase.
Sign-in/Register to view highlights & summary 
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call