Magnetic Fe3O4-Ag0 nanocomposites for effective mercury removal from water

In this study, magnetic Fe3O4 particles and Fe3O4-Ag0 nanocomposites were prepared by a facile and green method, fully characterized and used for the removal of Hg2+ from water. Characterizations showed that the Fe3O4 particles are quasi-spherical with an average diameter of 217 nm and metallic silver nanoparticles formed on the surface with a size of 23-41 nm. The initial Hg2+ removal rate was very fast followed by a slow increase and the maximum solid phase loading was 71.3 mg/g for the Fe3O4-Ag0 and 28 mg/g for the bare Fe3O4. The removal mechanism is complex, involving Hg2+ adsorption and reduction, Fe2+ and Ag0 oxidation accompanied with reactions of Cl- with Hg+ and Ag+. The facile and green synthesis process, the fast kinetics and high removal capacity and the possibility of magnetic separation make Fe3O4-Ag0 nanocomposites attractive materials for the removal of Hg2+ from wate

TERBIUM AND BARIUM CODOPED MESOPOROUS SILICA NANOPARTICLES WITH ENHANCED OPTICAL PROPERTIES

In this study, we showed for the first time that barium (Ba) codoping improves the luminescent properties of terbium (Tb)-doped SiO2 nanoparticles (NPs). In particular, the quantum yield (QY) of SiO2-Ba,Tb NPs was found to be ~10.7%, whereas the QY of bare SiO2-Tb NPs was only ~4.3%. Several mechanisms for luminescence enhancement have been proposed. We strongly believe that this methodology can be used to create alternative silica-based NPs with improved optical characteristics