A new and facile route has been developed to synthesize ultrafine nanowires, superthin nanoflakes and uniform nanodisks of beta-Ni(OH)(2) using ethanol as the growth media under hydrothermal conditions for the first example. The results show that beta-Ni(OH)(2) nanowires possess single-crystal structures with diameters of 2.0 +/- 0.5 nm and lengths of 22 +/- 5 nm; beta-Ni(OH)(2) nanoflakes have thin thicknesses (< 5 nm) and large areas (> 200 nm(2)); and the uniform nanodisks present hexagonal shapes with diameters of 150-180 nm and thicknesses of 20-25 nm. The proposed method here can be extended to synthesize other hydroxide and oxide nanostructures. (c) 2005 Elsevier B.V. All rights reserved.