Full‐Component Recyclable and Electrical Insulating Lignocellulosic‐Encapsulated Liquid Metal for Efficient Thermal Management

Abstract Applying advanced thermal interface materials (TIMs) to fill the air gaps between microelectronic material surfaces and the radiator is an effective method for reducing thermal contact resistance and ensuring the efficient and stable operation of electronic devices. However, most of the conductive and difficult‐to‐recycle TIMs limit the economic and safe application of this technology at scale. In this work, a full‐component recyclable and electrical insulating lignocellulosic‐encapsulated eutectic gallium–indium (LCE) is presented for efficient thermal management. Colloidal encapsulation and nanofiber‐bridging are used to fabricate non‐covalent and stable hierarchical interface structures. This structure achieves a eutectic gallium–indium (EGaIn) content as high as 97.8 wt.% and an electrical resistivity of 1.303 × 10 6 Ω m caused by a multi‐component synergy from lignin and cellulose nanofibers with abundant functional groups. The LCE coating delivers highly efficient, stable, and safe thermal dissipation, reducing the core temperature of a fully loaded central processing unit by 35 °C. When electronic devices reach the end of their service life, the LCE can be easily removed from their surfaces and achieve full‐component recovery. This research paves a new path for developing green advanced manufacturing processes and the sustainable application of economical, efficient, and environmentally friendly thermal management materials.