Chemically bonded phosphate ceramics reinforced with carbon nanotubes

We report herein, a scalable method for the preparation of alumina (Al2O3)-phosphate ceramics reinforced with carbon nanotubes (CNTs). All composites were manufactured by direct on-site growth of CNTs on ceramic particles via catalytic chemical vapour deposition. Introduction of catalyst metals to the substrate was achieved through two simple approaches, drip-coating and vacuum filtration, both of which have been reviewed. Transmission electron microscopy was utilised to investigate the interface between the Al2O3 surface and the in-situ CNTs. Resultant ceramics were produced by impregnating phosphoric acid into the Al2O3+CNT nanocomposite powder followed by die-pressing. In order to maintain the integrity of the CNTs, dehydration/curing was performed at 130-150○C. Scanning electron microscopy was elected to comparatively characterise the microstructure of this type of ceramic nanocomposite against its monolithic equivalent. Possible mechanisms by which specific features have formed are discussed.