Fine tuning of the sizes and phases of ZrO2 nanocrystals

Monodisperse and pure phase zirconia (tetragonal: T-ZrO 2 ; monoclinic: M-ZrO 2 ) nanocrystals with finely tuned sizes as well as ultrathin T-ZrO 2 nanowires have been selectively synthesized by a facile solvothermal method. For the first time, a diagram of the size to effective strain was mapped for both T-ZrO 2 and M-ZrO 2 , which gives a good explanation for the size- and cation doping-dependent stability of the two phases on the sub-10 nm scale. This work may expand our understanding of the phase properties of not only zirconia, but also various other polymorphic nanocrystals.