Sm doped mesoporous CeO2 nanocrystals: aqueous solution-based surfactant assisted low temperature synthesis, characterization and their improved autocatalytic activity
| Autor: | Amar Kundu, Bappaditya Mandal, S. Saha Ray, Aparna Mondal |
|---|---|
| Rok vydání: | 2016 |
| Předmět: |
Cell Survival
Surface Properties 02 engineering and technology 010402 general chemistry 01 natural sciences Antioxidants Catalysis law.invention Inorganic Chemistry Surface-Active Agents Pulmonary surfactant law Cell Line Tumor Humans Organic chemistry Calcination Particle Size High-resolution transmission electron microscopy Samarium Aqueous solution Chemistry Doping Temperature Water Cerium 021001 nanoscience & nanotechnology Nanocrystalline material 0104 chemical sciences Solutions Nanocrystal Chemical engineering Nanoparticles 0210 nano-technology Mesoporous material Porosity |
| Zdroj: | Dalton Transactions. 45:1679-1692 |
| ISSN: | 1477-9234 1477-9226 |
| DOI: | 10.1039/c5dt03688g |
| Popis: | Mesoporous Sm(3+) doped CeO2 (Ce-Sm) with a nanocrystalline framework, a high content of Ce(3+) and surface area (184 m(2) g(-1)), have been synthesized through a facile aqueous solution-based surfactant assisted route by using inorganic precursors and sodium dodecyl sulphate as a template. The XRD results indicate that the calcined Ce-Sm and even the as-prepared material have a cubic fluorite structure of CeO2 with no crystalline impurity phase. XRD studies along with HRTEM results confirmed the formation of mesoporous nanocrystalline CeO2 at a lower temperature as low as 100 °C. A detailed analysis revealed that Sm(3+) doping in CeO2 has increased the lattice volume, surface area, mesopore volume and engineered the surface defects. Higher concentrations of Ce(3+) and oxygen vacancies of Ce-Sm resulted in lowering of the band gap. It is evident from the H2-TPR results that Sm(3+) doping in CeO2 strongly modified the reduction behavior of CeO2 by shifting the bulk reduction at a much lower temperature, indicating increased oxygen mobility in the sample which enables enhanced oxygen diffusion at lower temperatures, thus promoting reducibility, i.e., the process of Ce(4+)→ Ce(3+). UV-visible transmission studies revealed improved autocatalytic performance due to easier Ce(4+)/Ce(3+) recycling in the Sm(3+) doped CeO2 nanoparticles. From the in vitro cytotoxicity of both pure CeO2 and Sm(3+) doped CeO2 calcined at 500 °C in a concentration as high as 100 μg mL(-1) (even after 120 h) on MG-63 cells, no obvious decrease in cell viability is observed, confirming their excellent biocompatibility. The presence of an increased amount of surface hydroxyl groups, mesoporosity, and surface defects have contributed towards an improved autocatalytic activity of mesoporous Ce-Sm, which appear to be a potential candidate for biomedical (antioxidant) applications. |
| Databáze: | OpenAIRE |
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