Strong europium luminescence in lanthan-euripium-erbium-calcium-vanadate nanocrystals, the result of codoping optimization

TL;DR

This study synthesizes lanthanum vanadate nanoparticles co-doped with calcium, europium, and erbium, revealing how dopant concentrations influence crystal structure and significantly enhance europium luminescence through optimized codoping.

Contribution

It elucidates the mechanisms by which calcium and erbium impurities affect europium luminescence and identifies compositions with improved luminescence intensity.

Findings

Crystal structure shifts from monoclinic to tetragonal with increased dopants.

Nanoparticles exhibit two distinct shapes.

Luminescence intensity depends on dopant-induced lattice and defect modifications.

Abstract

Co-doped with calcium, europium and erbium ions lanthanum vanadate crystalline nanoparticles are synthesized and investigated with a goal to clarify the mechanisms of calcium and erbium impurities effects on europium ions luminescence and to find compositions with enhanced luminescence intensity. The XRD analysis reveals dependence of crystal structure on dopants concentration: monoclinic crystal phase is observed for low dopant concentrations and content of tetragonal crystal phase increases with dopant concentrations increase. The SEM investigation reveals formation of nanoparticles with two types of shapes. Photoluminescence spectra consist of lines caused by inner transitions in the erbium and europium ions. It has been shown that dependence of the europium ions luminescence intensity on the calcium and erbium concentrations is caused by cumulative effects of dopants on crystal lattice structure, on defects in the first coordination sphere of the europium ions and on efficiency of excitation energy transfer.