Comparative study of optical and structural properties of electrospun 1-dimensional CaYAl3O7:Eu3 + nanofibers and bulk phosphor

Abstract

We report the optical and structural studies of Eu3+-doped 1-dimensional CaYAl3O7 nano-fiber phosphor. CaYAl3O7:Eu3+ phosphors were synthesized by electrospinning technique and the pristine nano-fibers were annealed at 900 degrees C to form well crystallized uniform fibers. Under ultraviolet excitation, the CaYAl3O7:Eu3+ exhibited red emission, due to transitions in the 4f states of Eu3+. In order to explore the difference between the quantum efficiency of nano-fiber and bulk CaYAl3O7:Eu3+ phosphor, detailed structural and optical analyses were carried out. The structural analysis of the CaYAl3O7:Eu3+ nano-fibers indicates that the structural environment surrounding the dopant Eu3+ ion was more unstable in nano-fiber when compared to a bulk sample. Decay curves for both the samples when fitted with double exponential decay model indicate that the nano-fiber has shorter decay time, arising from the larger contribution from the non-radiative decay, due to defect levels introduced in the host lattice.