A Thermochromic, Viscoelastic Nacre-like Nanocomposite for the Smart Thermal Management of Planar Electronics

• Published in: Nano-micro letters 2023-12, Vol.15 (1), p.170-170, Article 170
• Main Authors: Wang, Jiemin, Yang, Tairan, Wang, Zequn, Sun, Xuhui, An, Meng, Liu, Dan, Zhao, Changsheng, Zhang, Gang, Lei, Weiwei
• Format: Article
• Language: English
• Subjects: Adhesive strength; Boron nitride nanosheets; Contact resistance; Cooling; Electronics; Elongation; Engineering; Heat conductivity; Heat transfer; Nacre; Nacre-inspired composites; Nanocomposites; Nanoscale Science and Technology; Nanotechnology; Nanotechnology and Microengineering; Smart thermal management; Special issue on Thermally Conductive Materials with Focus on Nanoscale; Spreaders; Stretchability; Thermal conductivity; Thermal contact resistance; Thermal management; Thermal resistance; Thermochromic; Thermochromism; Thermodynamic properties; Viscoelastic; Viscoelasticity
• ISSN: 2311-6706; 2150-5551
• DOI: 10.1007/s40820-023-01149-8

Highlights Construction of a viscoelastic composite nacre with a ripple-like layered architecture through supramolecular interactions. Outstanding self-adhesion, self-healing and scrape-resistant mechanical and thermal properties. Utility as an integrated heat spreader and TIMs for “chameleon-like” thermal management of planar soft electronics. Cutting-edge heat spreaders for soft and planar electronics require not only high thermal conductivity and a certain degree of flexibility but also remarkable self-adhesion without thermal interface materials, elasticity, arbitrary elongation along with soft devices, and smart properties involving thermal self-healing, thermochromism and so on. Nacre-like composites with excellent in-plane heat dissipation are ideal as heat spreaders for thin and planar electronics. However, the intrinsically poor viscoelasticity, i.e., adhesion and elasticity, prevents them from simultaneous self-adhesion and arbitrary elongation along with current flexible devices as well as incurring high interfacial thermal impedance. In this paper, we propose a soft thermochromic composite (STC) membrane with a layered structure, considerable stretchability, high in-plane thermal conductivity (~ 30 W m −1  K −1 ), low thermal contact resistance (~ 12 mm 2  K W −1 , 4–5 times lower than that of silver paste), strong yet sustainable adhesion forces (~ 4607 J m −2 , 2220 J m −2 greater than that of epoxy paste) and self-healing efficiency. As a self-adhesive heat spreader, it implements efficient cooling of various soft electronics with a temperature drop of 20 °C than the polyimide case. In addition to its self-healing function, the chameleon-like behavior of STC facilitates temperature monitoring by the naked eye, hence enabling smart thermal management.