Capillarity‐Assisted 3D Patterning of Liquid Metal

Abstract Flexible electronics with sophisticated 3D architectures enable multidimensional functionalities and multi‐component integration, thus surpassing their 2D counterparts in soft robotics and wearable sensors. Because of its unique metallic and fluidic characteristics, liquid metal (LM) has proven to be an excellent material for fabricating flexible electronics. However, its low viscosity and high surface tension have primarily restricted LM to the creation of 2D‐patterned films on flat surfaces, significantly limiting the complexity and functionality of the resulting flexible devices. In this work, inspired by the capillary‐driven liquid flow in a hierarchical lattice matrix, a 3D patterning method is proposed for LM and extended to the fabrication of porous materials with flexible conductivity. The feasibility and versatility of the proposed method are showcased by fabricating tunable electromagnetic interference shielding materials, programmable 3D circuits, and customizable wearable sensors, highlighting its potential for promoting the development of integrated circuits and wearable electronics.