Synthesis and Characterization of Highly Fluorescent Multi-Coloured Upconversion Nanomaterials

Abstract

The current research project work essentially deals with the synthesis of highly bright fluorescent nanoparticles which have the ability to emit wavelength shorter than that of the pumped wavelength. The synthesis was carried out using thermal decomposition method to dope lanthanide ions into the host lattice using lanthanum oxides as precursors. The Upconversion NPs formed were either capped by oleylamine or oleic acid, yielding their dispersibility in organic solvents and preventing them from agglomeration. We developed UCNPs having varied colours which can prove useful for barcoding and imaging purposes. Further, we functionalised our NPs with silica using reverse micro-emulsion technique. These bifunctional nanocomposites increase the stability of upconversion materials and prevent the escape of rare earth ions from the lattice. The characterization for all the particles was carried out using XRD, EDAX, FTIR, DLS and Zeta potential analysis.