Impact of Ce/Zr Ratio in the Nanostructured Ceria and Zirconia Composites on the Selective CO₂ Adsorption.

ABSTRACT: High surface-area, mesoporous CeO₂, ZrO_2, and Ce-Zr composite nanoparticles were developed using the hydrothermal template-assisted synthesis method. Samples were characterized using XRD, N₂ physisorption, TEM, XPS, and FT-IR spectroscopic methods. The CO₂ adsorption ability of the obtained materials was tested under dynamic and equilibrium conditions. A high CO₂ adsorption capacity in CO₂/N₂ flow or CO₂/N₂/H₂O was determined for all studied adsorbents depending on their composition flow. A higher CO₂ adsorption was registered for Ce-Zr composite nanomaterials due to the presence of strong O^2- base sites and enriched surface oxygen species. The role of the Ce/Zr ratio is the process of the formation of highly active and selective adsorption sites is discussed. The calculated heat of adsorption revealed the processes of chemisorption and physisorption. Experimental data could be appropriately described by the Yoon-Nelson kinetic model. The composites reused in five adsorption/desorption cycles showed a high stability with a slight decrease in CO₂ adsorption capacities in dry flow and in the presence of water vapor.

SUBMITTER: Issa G 

PROVIDER: S-EPMC10490239 | biostudies-literature | 2023 Aug

REPOSITORIES: biostudies-literature