Thermal conductivity of carbon/boron nitride heteronanotube and boron nitride nanotube buckypapers
To date, there has been limited reporting on the fabrication and properties of macroscopic sheet assemblies (specifically buckypapers) composed of carbon/boron nitride core-shell heteronanotubes (MWCNT@BNNT) or boron-nitride nanotubes (BNNTs).
A team of researchers headed by the department and working alongside the University of Lancaster report in their paper* (which is featured on the cover of ACS Applied Nano Materials) on the synthesis of MWCNT@BNNTs via a facile method involving Atmospheric Pressure Chemical Vapour Deposition (APCVD) and the safe h-BN precursor ammonia borane. These MWCNT@BMMYs were used as sacrificial templates for BNNT synthesis by thermal oxidation of the core carbon. Buckypaper fabrication was facilitated by facile sonication and filtration steps.
To test the thermal conductivity properties of these new buckypapers, in the interest of thermal management applications, the authors developed a novel technique of advanced scanning thermal microscopy (SthM). They measured a 14% increase in thermal conductivity of the MWCNT@BBNT buckypaper relative to a controlled multiwalled carbon nanotube (MWCNT) buckypaper. The BNNT buckypaper exhibited approximately half the thermal conductivity of the MWCNT control, which they attribute to the turbostratic quality of the BNNTs.
To the best of the authors' combined knowledge, the work set out in this paper achieves the first thermal conductivity measurement of a MWCNT@BNNT buckypaper and of a BNNT buckypaper composed of BNNTs not synthesised by high energy techniques.
