Sol–gel synthesis of mesoporous spherical zirconia
Abstract
Mesoporous spherical zirconia (ZrO2) with a surface area of 113 m2 g−1 and average pore size of 5.0 nm is prepared by a sol–gel method with ZrOCl2·8H2O precursors and Sodium Dodecyl Sulfonate (SDS) templates with subsequent annealing at 500 °C in air. After calcination at 700 °C, the tetragonal phase transfers to monoclinic zirconia and the surface area is reduced to 26 m2 g−1. The mesoporous spherical structure, which is assembled by aggregation of the ZrO2 nanoparticles, is confirmed by characterization using low and wide-angle X-ray diffraction, Transmission Electron Microscopy (TEM) and Scanning Electron Microscopy (SEM). Mesoporous ZrO2 with a surface area of 113 m2 g−1 has a higher adsorption for Cs ion (357 mg g−1). For the 700 °C calcinated ZrO2, the absorption capacity at equilibrium is only 188 mg g−1.