Microstructures and Luminescent Properties of Sm3+-Doped KSr2Nb5O15 Prepared by Molten Salt Synthesis Method

To explore the excellent luminescent activator and associated luminescent behavior for the development of the potential coupling effect about luminescent and photochromic properties of novel KSr2Nb5O15 materials, the Sm3+-doped KSr2Nb5O15 powders have been prepared using the molten salt method. The effects of Sm3+ doping on the phases, morphologies, bonding vibrations, and luminescent properties have been investigated. The results show that the Sm3+-doped KSr2Nb5O15 powders can emit orange light (main peak wavelength around 601 nm) under the blue light (407 nm) excitation, and the optimal doping concentration of Sm3+ is 10 mol%. The main emission band is well matched with the photochromic absorption band of KSN host. The inversion symmetry of the environment around Sm3+ in KSN lattice and the electric dipole transition of Sm3+ are affected by the neighboring Nb(II)O-6 octahedrons. The related concentration quenching mechanism of luminescence and the effect of Sm3+ doping on the KSN lattice structures are further discussed.