Flexible multiwalled carbon nanotubes/cellulose nanofibers membrane with rapid temperature increasing induced by interface strengthening

Towards advanced electrical heaters with superior Joule heating property, high electrical conductivity has al-ways been critical issue. Herein, in addition to the commonly recognized factor of electrical conductivity, we proved that the composite interface poses significant effect on temperature increasing as electrical heaters. Specifically, direct fluorination utilizing F2/N2 was applied to selectively decorate the outer walls of multiwalled carbon nanotubes (MWCNTs) while keeping the inner tube intact, which was followed by compositing it with cellulose nanofibers (CNFs) to prepare F-MWCNTs/CNFs flexible membrane. Due to the enhanced electrostatic interaction at the interface and stronger phonon vibrational coupling, interfacial phonon diffusion was significantly improved, which facilitated a higher temperature increase rate in the F-MWCNTs/CNFs membrane compared to the unmodified MWCNTs/CNFs membrane when subjected to an electric field. This unique inter-facial effect holds promise for the development of high-performance electrical heaters with rapid response.