Retention Behaviours Of Carbon In Sol-Gel Derived ZrO2 Studied By Fourier Transform Infrared Spectroscopy

The carbon retention patterns based on evolution of FT-IR spectra at different calcination temperatures for ZrO 2 gels derived from Zr-n-propoxide-acetylacetone-water-isopropanol system are examined in detail. For most captured carbon species, carbon can be depleted at relatively low temperature of about 400°C. However, for lattice-included species, especially those incorporated into lattice during phase transition, a temperature around 900°C is needed to eliminate carbon in the gels. It is found that water treatment alone does not provide new routes for carbon retention in as-prepared ZrO 2 gels. When gels are pre-treated with Ni 2+ and water, new forms of carbon containing species can be observed. This is attributed to an inter-diffusion of Ni 2+ and ZrO 2 matrix and the catalytic effect of resultant solid solution NiO-ZrO 2 on the retained carbon.