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

Jiemin Wang; Tairan Yang; Zequn Wang; Xuhui Sun; Meng An; Dan Liu; Changsheng Zhao; Gang Zhang; Weiwei Lei

doi:10.1007/s40820-023-01149-8

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

Nanomicro Lett. 2023 Jul 5;15(1):170. doi: 10.1007/s40820-023-01149-8.

Authors

Jiemin Wang¹, Tairan Yang², Zequn Wang³, Xuhui Sun³, Meng An⁴, Dan Liu⁵, Changsheng Zhao⁶, Gang Zhang⁷, Weiwei Lei⁸

Affiliations

¹ College of Biomedical Engineering, Sichuan University, Chengdu, 610064, People's Republic of China.
² Institute for Frontier Materials, Deakin University, Waurn Ponds Campus, Locked Bag 20000, Geelong, Victoria, 3220, Australia.
³ College of Mechanical and Electrical Engineering, Shaanxi University of Science and Technology, Xi'an, 710021, People's Republic of China.
⁴ College of Mechanical and Electrical Engineering, Shaanxi University of Science and Technology, Xi'an, 710021, People's Republic of China. anmeng@sust.edu.cn.
⁵ Institute for Frontier Materials, Deakin University, Waurn Ponds Campus, Locked Bag 20000, Geelong, Victoria, 3220, Australia. dan.liu@deakin.edu.au.
⁶ State Key Laboratory of Polymer Materials Engineering, College of Polymer Science and Engineering, Sichuan University, Chengdu, 610065, People's Republic of China. zhaochsh70@scu.edu.cn.
⁷ Institute of High Performance Computing A*STAR, Singapore, 138632, Singapore. zhangg@ihpc.a-star.edu.sg.
⁸ Institute for Frontier Materials, Deakin University, Waurn Ponds Campus, Locked Bag 20000, Geelong, Victoria, 3220, Australia. weiwei.lei@deakin.edu.au.

Abstract

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 mm² 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.

Keywords: Boron nitride nanosheets; Nacre-inspired composites; Smart thermal management; Thermochromic; Viscoelastic.