Synthesis of NiO nanowires by a sol-gel process

A sol-gel process and subsequent calcination was employed to fabricate NiO nanowires. It is identified that the obtained NiO nanowires are hexagonal and single crystalline in nature. It is also found that some of the nanowires branch. The formation mechanism of NiO nanowires has been discussed. It is considered that the sol-gel process in which the citric acid acted as the chelate played a critical role in the formation of NiO nanowires, and the vapor-solid (VS) mechanism was responsible for the formation of the nanowires. (c) 2005 Elsevier B.V. All rights reserved.