High Surface‐Area Ceria Aerogel

Abstract

Ceria (CeO 2 ) aerogels with high surface area and high porosity have been prepared. Ce‐methoxyethoxide diluted in excess methoxyethanol was slowly hydrolyzed to yield a gel, which was then supercritically dried in CO 2 . Both as‐synthesized and annealed aerogels were examined by X‐ray powder diffraction, infrared spectroscopy, scanning electron microscopy, and BET surface area and pore‐size analyses. Thermal analysis of the as‐synthesized gel showed it to contain only ∼5 wt% residual organics, which were removed by 300°C under oxygen. The unheated ceria aerogel was crystalline and exhibited a specific surface area of 349 m 2 /g with average pore diameter of ∼21.2 nm and 90% porosity. Heat treatment led to a reduction of porosity and pore size, as would be expected, but the extremely narrow pore‐size distribution of the aerogel was retained.