Templateless, Plating‐Free Fabrication of Flexible Transparent Electrodes with Embedded Silver Mesh by Electric‐Field‐Driven Microscale 3D Printing and Hybrid Hot Embossing

Abstract

performance, transparent conductive oxides, as represented by indium tin oxide (ITO), have been mostly used widely for transparent electrodes (TEs) in the past few decades. However, the inherent properties of ITO such as brittleness and poor flexibility hinder its applications for flexible and stretchable optoelectronic products. [10] Hence, many alternatives to ITO have been developed to address these challenges for the next generation of FTEs, such as graphene, [11] carbon nanotubes, [12,13] conductive polymers, [14][15][16][17][18] transparent thin metal films, [19,20] random metal nanowires, [2,21] regular metalmesh, [22,23] and hybrid materials. [24,25] Among these FTEs, metal-mesh possesses excellent mechanical flexibility and optoelectronic properties. In particular, the trade-off between low sheet resistance and the high transmittance of TEs can be parametrically designed and further optimized by simply changing the line width, pitch, aspect ratio (AR), shape, and arrangement of the mesh. The metal mesh can be fabricated with a low-cost and large-area manufacturing process (such as solution-process), which can be carried out in a vacuum-free environment and usually requires only a low temperature process. [26][27][28][29][30] So far, FTEs based on metal mesh Flexible transparent electrodes (FTEs) with an embedded metal mesh are considered a promising alternative to traditional indium tin oxide (ITO) due to their excellent photoelectric performance, surface roughness, and mechanical and environmental stability. However, great challenges remain for achieving simple, cost-effective, and environmentally friendly manufacturing of high-performance FTEs with embedded metal mesh. Herein, a maskless, templateless, and plating-free fabrication technique is proposed for FTEs with embedded silver mesh by combining an electric-field-driven (EFD) microscale 3D printing technique and a newly developed hybrid hot-embossing process. The final fabricated FTE exhibits superior optoelectronic properties with a transmittance of 85.79%, a sheet resistance of 0.75 Ω sq −1 , a smooth surface of silver mesh (R a ≈ 18.8 nm) without any polishing treatment, and remarkable mechanical stability and environmental adaptability with a negligible increase in sheet resistance under diverse cyclic tests and harsh working conditions (1000 bending cycles, 80 adhesion tests, 120 scratch tests, 100 min ultrasonic test, and 72 h chemical attack). The practical viability of this FTE is successfully demonstrated with a flexible transparent heater applied to deicing. The technique proposed offers a promising fabrication strategy with a cost-effective and environmentally friendly process for high-performance FTE.

Cost-Effective Fabrication of Transparent Strain Sensors via Micro-Scale 3D Printing and Imprinting

“…The intersection points cannot be lapped when printing the grid structure, which is unfavorable for PDMS films with manufactured channel structures [ 41 ]. Silver grid printing has good consistency and neat intersections and is a simple process, which is suitable for master molds of PDMS films with channel structure manufacturing [ 42 ]. The silver grid structure (width of 20 µm; five layers) was deposited on the hydrophobic glass surface using EFD microscale 3D printing technology and cured at 100 °C for 30 min to enhance the hardness of the silver paste structure ( Figure 1 a).…”

“…In this study, an efficient, low-cost, and mass-produced EFD micro-scale 3D printing [ 41 , 42 , 43 , 44 , 45 , 46 ] and molding hybrid method is proposed to fabricate PDMS channel films. MWCNTs were filled into PDMS films with channel networks to prepare flexible strain sensors with high sensitivity, transparency, and stretchability.…”

Flexible transparent electrodes based on metallic micro–nano architectures for perovskite solar cells

“…Ordered MMNAs are a kind of metal mesh or grid with regular micro-nano primary cells and periods. The metal grids can be fabricated by ink-jet printing, [156][157][158] screen printing, 159 gravure printing, 43,160,161 self-assembling, 82 lithographic imprinting, 132,133 laser direct writing, 65,134 electrochemical deposition, 135,136 thermal evaporation, 162 or the combination process of these methods. 163,164 Among these methods, printing methods are widely used to fabricate flexible metal grids, due to the low processing temperature and large-scale accessibility.…”

Recent Advances in Design and Preparation of Polymer-Based Thermal Management Material

“…3D printing is an emerging technology, which can construct programmed microscopic and macroscopic structures [ 89 , 90 ], to realize the orderly stacking of thermally conductive fillers. Guo et al [ 86 ] used 3D printing technology to prepare graphene/thermoplastic polyurethane (PU) composites.…”