Thermal properties of CNT-Alumina nanocomposites

Carbon nanotube-alumina (CNT-Al2O3) nanocomposites have been synthesized by direct growth of CNTs on alumina by chemical vapor deposition (CVD) and the as-grown nanocomposites were densified by spark plasma sintering (SPS). The thermal properties of carbon nanotube-alumina composites have been investigated as a function of CNT content and the sintering temperature. The notably enhanced thermal properties were achieved including a heat capacity of 6.09 J/g K at 400 °C in the 19.10 wt% CNT-Al2O3 nanocomposites sintered at 1450 °C, a thermal diffusivity of 13.98 mm2/s, and a thermal conductivity of 90.44 W/mK in the 7.39 wt% CNT-Al2O3 nanocomposites sintered at 1550 °C. Hence, CNTs are considered to be able to form a new generation of engineered CNT-ceramic materials offering extremely improved thermal properties.