Synthesis of boron nitride nanotubes <i>via</i> chemical vapour deposition: a comprehensive review

Boron nitride nanotubes (BNNTs) have been synthesized by various methods over the last two decades. Among the various growth techniques, chemical vapor deposition (CVD) is one of the best methods for the synthesis of BNNTs in terms of quality and quantity. It offers relatively easy control of different growth parameters such as growth mechanism, experimental set up, precursor variables, catalyst type and temperature, and hence has become very convenient to grow BNNTs with desired size and morphologies leading to various advanced applications. Here, we present a comprehensive review on BNNT growth by CVD techniques ranging from catalytic to plasma assisted CVD. Moreover, the importance of certain variables for an efficient production of BNNTs, and their effects on the size and morphology of the tubes are also discussed elaborately.