Self-catalytic solution for single-crystal nanowire and nanotube growth.

Vast majority of nanowires is grown by the chemical vapor deposition (CVD), molecular beam epitaxy (MBE), metal-organic CVD (MOCVD), or the laser ablation method via the vapor-liquid-solid (VLS) route. Others are grown via the oxide-assisted route. In this investigation a self-catalytic synthesis route based on VLS formalism and suitable for the CVD, MBE, MOCVD, or the laser ablation method has been described. Various issues pertaining to growth kinetics, nanowire alignment, diameter distribution, and nanotube formation have been addressed. The strength of the self-catalytic route has been highlighted. As this route does not make use of foreign element catalytic agents to mediate the synthesis, it suffers from difficulties. Attempts have been made to elucidate means to overcome these difficulties. Attempts have also been made to explain the means to separate the nanowires thus produced from the substrate/scaffold, and to control their physicochemical characteristics.