Influence of counter-ions on the self-assembly of ZrO2 nanodisks

In three strong inorganic acidic conditions (HNO(3), HCl and H(2)SO(4)), we have prepared a series of air-water interfacial zirconium dioxide (ZrO(2)) films at normal temperature via a self-assembly technique, by using dodecylbenzenesulfonic acid (DBSA) as template and Zr(OC(4)H(9))(4) as precursor. X-ray diffraction (XRD), transmission electron microscope (TEM), UV-vis and fluorescence spectra have been used to characterize the ZrO(2) films. Results show that a number of worm-like mesoporous nanodisks and ambiguously mesoporous nanodisks are observed in the ZrO(2) films with NO(3)(-) and SO(4)(2-) counter-ions, respectively. Remarkably, a great many perfect target-like multiring nanodisks are obtained in the ZrO(2) sample with Cl(-) counter-ion. The self-assembly mechanism for ZrO(2) nanodisks has been purposely discussed. A model based on the structural changes with respect to the influence of counter-ions on the self-assembly of ZrO(2) nanodisks is therefore proposed. In addition, the structural changes for the ZrO(2) films self-assembled at a higher temperature have been discussed in combination with the influence of counter-ions.