Abstract
Self-assembled CaWO4:Sm3+ microspheres were prepared via surfactant (sodium dodecyl sulfate) mediated hydrothermal method. The effect of pH and the concentration of surfactant on the morphology and photoluminescence of the synthesized phosphors have been studied. Samples were characterized by X-ray diffractometry (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and photoluminescence spectroscopy. The microspheres were found to have an average size of 1–2 µm. They were mesoporous in nature and constituted of nanocrystals of about 10–30 nm dimension. The TEM images revealed the interlinking framework of the nano-sized constituents which consequently lead to the formation of mesoporous microspheres. The lowering of pH causes a slight reduction in the size of microspheres which could have been attributed to loss of OH from the nanoparticle surface and subsequent retardation in the adsorption of growing molecular CaWO4:Sm3+ units. Also, as pH increases, crystallinity decreases. The increase in amount of SDS reduced the crystallinity of the materials, destroyed the monodispersity of microspheres and lowered the luminescence output. It was found that lower pH and higher monodispersity of microspheres are quite favourable for high luminescence output.
Highlights
The synthesis and fabrication of nano- or microstructures with uniformly well-defined size and morphology is highly important
This work presents the successful synthesis of CaWO4:Sm3? microspheres via conventional hydrothermal method using sodium dodecyl sulphate (SDS) as soft template
The microspheres are found to be mesoporous in nature with the constituting nanodimensional units having the size of 10–30 nm as revealed from the micrographs of scanning electron microscopy (SEM) and transmission electron microscopy (TEM)
Summary
The synthesis and fabrication of nano- or microstructures with uniformly well-defined size and morphology is highly important. The increase in amount of SDS reduced the crystallinity of the materials, destroyed the monodispersity of microspheres and lowered the luminescence output. The effect of variation of pH of the reaction medium and surfactant concentration on the morphology and photoluminescence of the phosphor materials has been studied. For the samples prepared at different SDS concentrations, i.e. 50 and 100 mM, the pH is adjusted to 9.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
