Electrohydrodynamic Jet Printed 3D Metallic Grid: Toward High-Performance Transparent Electrodes

2D metallic grids that consist of various nanomaterials that are suitable for the replacement of indium tin oxide in transparent electronics (TEs) manufacturing. High-resolution conductive grids with large open areas are often required while considering high transmittance. However, previous research shows that this kind of TE often cannot have high transmittance and low sheet resistance simultaneously; it hinders the fabrication techniques and materials from practical applications. Herein, direct fabrication of a high-performance TE through electrohydrodynamic jet 3D printing technique is reported. Micro-scale 3D metallic grids with an aspect ratio of above-5 were printed on a polyester film using Ag nanoparticles. The metal grids with high aspect ratios exhibit an average sheet resistance of 3 Ω sq⁻¹ and transparency of 96%. Both optical and electrical performances are significantly enhanced for which the large cross-section of the metallic grid is contributed. Furthermore, the flexibility of printed TE is also characterized by the bending and recovering test. It is believed that the printed flexible TE, which utilize a high aspect ratio, 3D metallic grids may replace the conventional ITO glass for which both high transmittance and conductivity are achieved with economic efficiency.