Surfactant assisted synthesis of high surface area ceria modified mesoporous tetragonal zirconia powder and its chromium adsorption study

Abstract

Mesoporous zirconia modified by ceria has been synthesized through a surfactant-assisted route by using zirconyl oxychloride and ceric ammonium nitrate as precursors and dodecylamine as a template. The as-synthesized inorganic-template hybrid possesses high surface area (275 m 2 g −1) and large pore volume (0.52 cm 3 g −1). A template-free mesoporous zirconia–ceria with a decreased surface area of 80 m 2 g −1 and pore volume of 0.07 cm 3 g −1 was formed by heat treatment of the as-synthesized matrix at 500 °C for 2 h. The introduction of as small as 2 mol% ceria into the zirconia lattice has helped in stabilizing the technologically important tetragonal (t-) phase of zirconia up to 800 °C. The sample obtained even after calcination at 500 °C exhibits high adsorption capacities, ∼85% for chromium(VI) ions from aqueous solutions without any adjustment of pH, at room temperature, and within a period as short as 1 h. These present studies show that the mesoporous zirconia modified by ceria could be considered as a potential adsorbent for removing toxic Cr(VI) ions from aqueous solutions.