Study of The Effects of Multiple Monolayers of Polyvinylidene Fluoride

Indianapolis, IN

A material that can spontaneously polarize due to the application of an electric field is known as a ferroelectric material. This spontaneous polarization is due to the dipoles aligning to the direction of the applied electric field. By graphing the polarization of the crystal against the applied electric field a hysteresis graph is produced. By reversing the direction of the applied electric field, the polarization of the crystal is reversed, which gives the hysteresis graph a characteristic “S” shape. The width of the hysteresis graph is known as the coercivity, which is the amount of electric field that is required to revert the polarization of the crystal back to zero net-polarization. A well-known ferroelectric material is Polyvinylidene Fluoride; which is the subject of this study. The hypothesis of this study is that by adding more nanometers of Polyvinylidene Fluoride to increase the thickness of a sample of Polyvinylidene Fluoride, the coercivity of the hysteresis graph will become smaller as the thickness becomes greater. This hypothesis was tested by finding the coercivity of several test sample each with a different number of monolayers. By testing different samples coercivity and plotted the coercivity against the number of monolayers, which subsequently formed a power law decay curve. This power law decay confirmed the hypothesis, that as the thickness increases the coercivity of the polyvinylidene fluoride will decrease.