Cellulose based Janus-aerogel composite as magnetically actuated thermal interface materials

A Janus-aerogel composite is developed, integrating high thermal conductivity and magnetic-driven positioning. • Liquid metal-constructed continuous networks greatly reduce intrinsic thermal resistance for efficient heat dissipation. • The composite displays efficient heat dissipation and stability in LEDs, CPUs, and electricity transformer boxes. With the miniaturization of electronic devices, interfacial thermal management encounters substantial challenges. However, conventional thermal dissipation materials incorporated with rigid thermal fillers fail to construct tight, durable, and tunable thermal conduction pathways, thereby limiting their application in electronic device heat dissipation. This work reports a magnetically actuated thermal-conductive NdFeB/cellulose nanofiber (CNF)/polyvinyl alcohol (PVA)/liquid metal (LM) (MCPL) aerogel film with a Janus inner structure, in which the flexible LM-CNF/PVA constructs an efficient thermal conduction network, LM-enriched bottom surface provides higher in-plane conductivity, and the NdFeB particles-stratified layer endows the excellent magnetic actuation. The LM forms continuous thermal conduction pathways within the aerogel network, thus significantly reduces the intrinsic thermal resistance (3.16 cm 2  K W −1 ) and achieves good in-plane thermal conductivity (1.632 W m −1  K −1 ). Unlike conventional thermal interface materials, the MCPL enables precise positioning and dynamic adhesion under magnetic regulation, which effectively realizes tunable interfacial thermal conductivity and enhances interfacial affinity. When deployed in LEDs, CPUs, and electrical transformer boxes, the MCPL exhibit controllable thermal conduction behavior, superior heat dissipation capacity and long-term operational stability. This material offers an innovative strategy for intelligent thermal management of electronic devices and facilities. Download: Download high-res image (386KB) Download: Download full-size image