Highly Flexible Few-layer Ti3C2 MXene/Cellulose Nanofiber Heat-spreader Films with Enhanced Thermal Conductivity

MXenes, two-dimensional transition metal carbides, exhibit excellent properties in many fields such as energy storage. And the first discovered, Ti3C2 has been widely used in lithium ion battery. However, thermal property and delamination of few-layer MXenes were insufficiently explored. In this work, Few-layer Ti3C2 nanosheets were prepared under ultra-high pressure and by low temperature exfoliation. And a flexible cellulose nanofiber (CNF)/Ti3C2 composite film was fabricated by simple vacuum-assisted filtration. The heat spreader of Ti3C2/CNF papers exhibits in-plane and out-of-plane thermal conductivity of 11.57 and 1.57 W m-1 K-1 with loading 50 wt% of filler, respectively. Moreover, the synthesized Ti3C2/CNF composite films presented outstanding flexibility because the films can be fold to any shape, which enables Ti3C2/CNF composite films to be the potential application in flexible electronic devices for heat dissipation