Microscale hybrid 3D printed ultrahigh aspect ratio embedded silver mesh for flexible transparent electrodes

Increasing the aspect ratio (AR) of embedded metal meshes (EMMs) is an effective approach to solve the “trade-off” effect of flexible transparent electrodes (FTEs). However, achieving low-cost and green manufacturing of ultrahigh AR EMM still faces great challenges. Here, we report a novel solution for the ultrahigh AR EMMs by microscale hybrid printing nano silver paste. An improved printed nozzle is introduced to facilitate the stable electric-filed-driven 3D printing, then the imprinting process is used to achieve an EMM with AR of up to 20.1, which is the highest AR ever reported. The fabricated FTE exhibits unprecedented photoelectric performance with a figure of merit of up to 88,194 and excellent optoelectronic properties after rigorous mechanical and environmental stability tests. Its practical application was also demonstrated to be feasible through flexible transparent heater and electromagnetic shielding. The proposed method provides a promising strategy to fabricate FTEs with ultrahigh AR EMM.