This study examined the growth mechanism of In(OH)(3) nanocubes formed during the hydrothermal reaction of a solution containing In(NO3)(3)center dot 6H(2)O, NaOH, and H2O2. Regardless of the pH of the stock solution, an abnormal growth behavior was detected i.e. only a few particles grew to a very large size. However, the mean edge lengths of the nanocubes decreased significantly from 100-450 to 20-70nm with increasing pH of the stock solution from 4 to 8.8. This was attributed to the active nucleation of In(OH)(3) nanocubes at pH 8.8 and the limitation of their growth due to the restricted source materials. The growth of In(OH)(3) nanocubes was explained in terms of a two-dimensional nucleation and growth mechanism. (C) 2008 Elsevier B.V. All rights reserved.