Experimental and Simulation Studies of the Effects of Nanosecond Pulse Frequency on the Dielectric Motion of BNNSs

Abstract

Application of nanosecond pulsed electric fields to insulating nanoparticles can be used to prepare oriented high-performance composites, but the mechanism and related laws are still unclear. Therefore, in this article, highly insulating boron nitride nanosheet (BNNS) nanoparticles are selected, their alignment motions under different nanosecond intraburst frequencies (100 Hz–1 MHz) are studied for the first time in both experiments and simulations, and the two sets of results are compared and analyzed. The results show that the simulation results based on COMSOL are in good agreement with the experimental results, the variations in the local orientation angle with time and the local orientation time with intraburst frequency can be expressed by an allometric function, and the variation in the center-to-center distance with time can be described by an exponential decay function. Further experiments show that with the continuous application of the pulsed electric field, short chains of BNNSs continue to move to form longer chains, and long chains of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$342~\mu \text{m}$ </tex-math></inline-formula> form under the external application of the pulsed electric field for 3 min. The good agreement between experiments and simulations verifies the strong reliability of the proposed theory and the established mathematical model for predicting the orientation alignment motion of BNNS particles. The theory and simulation method can be used as effective tools to predict the trajectories of nanoparticles under a nanosecond pulsed electric field and their final alignment into chains.