Improving a nozzle tip with a guard ring for an electrospray system

Abstract

The Electrospray technique allows the formation of small droplets from aqueous solutions that may contain nanoparticles of different materials in suspension, leading to the deposition of layers of the nanoparticles. The geometry of the nozzle and the electric field lines from the tip to substrate are key parameters to concentrate the jet of nanodroplets to enhance the deposition control. This work examines the introduction and effect of a guard ring placed at a specific distance from the nozzle. We have been able to make observations with a CCD camera of the fast formation of the Taylor cone with a long elongated jet of deionized water when both the guard ring and substrate are connected to ground. Main results show that the guard ring allows to concentrate the spray jet, reduces the voltage required to shape the cone and reduce the dispersion of the deposit.