Ultrarobust Photothermal Materials via Dynamic Crosslinking for Solar Harvesting

Abstract Highly efficient and mechanically durable photothermal materials are urgently needed for solar harvesting, but their development still remains challenging. Here, inspired by the hierarchically oriented architecture of natural spider silk, an ultrarobust liquid metals (LMs)/polymer composite is presented via dynamic crosslinking based on the unique mechanical deformable characteristic of LMs. Dynamically cross‐linked core–shell structured LMs droplets can be squeezed along with the orientational crystallization of polymer chains during drawing, thus enabling LMs nanoparticles to be uniformly programmed in the rigid polyethylene nanofiber skeleton. The resultant composite exhibits an unprecedented combination of strong broad‐band light absorption (96.9–99.3%), excellent photothermal conversion ability, remarkable mechanical property (tensile strength of 283.7 MPa, which can lift 200 000 times its own weight), and long‐term structural reliability (bearing 100 000 bending cycles). A powerful and durable solar thermoelectric generator system for real‐environmental solar‐heat‐electricity conversion is further demonstrated, providing a valuable guidance for the design and fabrication of high‐performance solar‐harvesting materials.