Experimental Assessment and Data-Driven Modeling of 3D-Printed Conductive Patterns on Electrospun Substrates

Flexible electronics (FE) have emerged as a key technology with applications in various fields, e.g., energy storage and bioelectronics. Electrospinning (ES), inkjet printing (IJP), and intense pulsed light (IPL), constitute a flexible multi-stage system capable to handle high customization requirements. The ES/IJP/IPL system is used for flexible substrate fabrication, conductive patterns printing, and sintering, respectively. Although the ES/IJP/IPL system seems to be suitable for on-demand FE devices manufacturing, the correlation of materials and process parameters of individual stages (i.e., ES/IJP/IPL) with the FE devices performance (i.e., conductivity) remains unexplored. Therefore, the objective of this paper is to evaluate the integration of ES, IJP, and IPL, for future production of high-performance FE devices. Various materials and process parameters are used to investigate their influence on the FE device resistivity, including Polyacrylonitrile (PAN) at different concentrations in ES, distinct number of ink layers in IJP, and several sintering configurations in IPL. The study includes (1) an experimental assessment of the electrospun membrane morphology (e.g., fiber diameter) and ink coating characteristics (e.g., homogeneity) using scanning electron microscopy (SEM), and (2) a logistic regression (LR) classification model to predict FE conductive feasibility. The results indicate that membranes with larger fiber diameters benefit ink penetration, printed layer/multilayer consistency, and conductivity. This is corroborated with the LR model, where the number of printed layers, fiber diameter, and collector type, are identified as significant factors for accurately predicting conductive patterns feasibility.