Morphology-Controllable Preparation of CeO2 Materials for CO2 Adsorption

摘要

Three morphology controllable CeO2 crystals were successfully synthesized via the thermal decomposition of CeCO3OH precursors, which was newly prepared on the basis of a simple and template-free hydrothermal reaction between CeCl3 solution and a CO2-storage material (CO2SM). In the formation processes of three CeCO3OH precursors, the CO2SM could be newly used as raw material and structural director. Meanwhile, the results presented the wider pH values (5.24-8.35) for isoelectric point of CeCO3OH precursors. After the CeCO3OH precursors were isolated, the filtrate could be recycled to absorb CO2 again and prepare CeCO3OH precursors with two special polymorphs. Three as-prepared CeO2 crystals by annealing three CeCO3OH precursors at 500 ℃ for 4 h showed the maximum adsorption amounts of 23.5, 18.7 and 20.5 mg/g for 8% CO2/N2 mixture. As a result, this work provided the wider pH values for isoelectric point of CeCO3OH precursors and a simple method for the preparation of CeO2 crystals with a short time and CO2 adsorption properties.