Controlled fabrication and property studies of nickel hydroxide and nickel oxide nanostructures

In this article, different Ni(OH)(2) nanostructures have been synthesized through a facile template-and surfactant-free approach. By adding additives, changing the nickel source or choosing different solvents, nickel hydroxide can be controllably synthesized from beta-Ni(OH)(2) nanodisks to hierarchical beta-Ni(OH)(2) superstructures assembled by nanoplate building blocks. This approach is very easy and only 2-3 chemicals and no template or surfactant are used. The growth rate has the most influence on the formation of beta-Ni(OH)(2) nanostructures with different assembling modes. The obtained beta-Ni(OH)(2) samples show different electrochemical behaviors with different superstructures. Furthermore, cubic nickel oxide (NiO) crystals with nanopores have also been successfully obtained by thermal decomposition of the as-synthesized beta-Ni(OH)(2) in air. The magnetic parameters of these NiO nanostructures are different and related to the change of the superstructures.