Warm white light emitting ThO₂:Sm³⁺ nanorods: Cationic surfactant assisted reverse micellar synthesis and Photoluminescence properties

Graphical abstract: - Highlights: • ThO₂:Sm³⁺ nanoparticles have been synthesized using cationic surfactant assisted reverse micellar route. • HRTEM shows the formation of thoria nanorods. • Photoluminescence investigation shows host as well as samarium ion emission. • Time resolved fluorescence spectroscopy shows the presence of two types of samarium ion in thoria host. - Abstract: Sm³⁺ activated thorium oxide nanorods were synthesized by cationic surfactant assisted reverse micellar route. Phase purity, morphological and luminescent properties were investigated by X-ray diffraction, high resolution transmission electron microscopy and photoluminescence spectroscopy. Upon UV light excitation (245 nm), ThO₂:Sm³⁺ exhibited host emission at 447 nm, along with characteristic emission lines of Sm³⁺ at 569, 609, 662 and 716 nm. Lifetime spectroscopy shows the presence of two types of Sm³⁺ (τ = 1.1 ms and 4.9 ms) with different asymmetric ratios