Improving Conductivity of Reduced Infill 3D-Printed Electrodes Through Tuning Infill Pattern and Orientation

3D printing has been shown to be a highly effective approach for the reproducible manufacturing of composite carbon electrodes. Various printing parameters have been effectively shown to enhance the electrochemical performance of 3D-printed electrodes through reducing contact resistance; however, most of these studies have been conducted using 100% infill electrodes. Our study explored how the infill pattern and printing orientation can impact the electrochemical performance of reduced infill carbon black/polylactic acid (CB/PLA) electrodes. We printed 30% infill CB/PLA electrodes in linear, grid, triangle, and wiggle infill patterns in both horizontal and vertical orientations and evaluated the performance using cyclic voltammetry, conductivity imaging, and contact angle measurements. CB/PLA electrodes made using a grid infill pattern in horizontal orientation and a linear infill pattern with vertical orientation had the highest current and lowest difference between the anodic and cathodic peak potentials for an inner-sphere redox probe. This study provides vital insight that the choice of infill pattern is important when printing in different orientations. The findings presented have significant implications on effective choice of printing parameters when crafting 3D-printed electrodes and electronic components.