Fabrication of Nonconductive Microscale Patterns on Ion Exchange Membrane by Laser Process

Abstract

The electroconvection generated on the surface of an ion exchange membrane (IEM) is closely related to the electrical/chemical characteristics or topology of the IEM. In particular, when non-conductive regions are mixed on the surface of the IEM, it can have a great influence on the transfer of ions and the formation of nonlinear electroconvective vortices, so more theoretical and experimental studies are necessary. Here, we present a novel method for creating microscale non-conductive patterns on the IEM surface by laser ablation, and successfully visualize microscale vortices on the surface modified IEM. Microscale (~300 µm) patterns were fabricated by applying UV nanosecond laser processing to the non-conductive film, and were transferred to the surface of the IEM. In addition, UV nanosecond laser process parameters were investigated for obvious micro-pattern production, and operating conditions were optimized, such as minimizing the heat-affected zone. Through this study, we found that non-conductive patterns on the IEM surface could affect the generation and growth of electroconvective vortices. The experimental results provided in our study are expected to be a good reference for research related to the surface modification of IEMs, and are expected to be helpful for new engineering applications of electroconvective vortices using a non-conductive patterned IEM.