CeO2 nanocrystals (NCs) have attracted increasing interest over the past few years, in particular for their use in catalytic reactions. Syntheses mediated by near- and supercritical alcohols have proven to be innovative ways to obtain CeO2 NCs with controlled crystallite sizes (from 3 to 8 nm depending on the alcohol) and surface functionalities, with alcohol moieties. When submitted to a thermal treatment at 500 °C, required to desorb/degrade surface organic species, these powders displayed different behaviors depending on the alcohol used during the synthesis. Cerium oxide powders synthesized in sc-MeOH, sc-EtOH and sc-iPrOH undergo sintering during treatment at 500 °C, with a decrease of their specific surface area. Conversely, those synthesized in sc-BuOH, nc-PentOH and nc-HexOH keep their initial crystallite sizes and morphology, but show a great enhancement of their specific surface area (up to 200 m(2) g(-1)), which is unprecedented after such a thermal treatment.
Keywords: alcohols; cerium oxide; specific surface area; supercritical fluids; thermal treatment.
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