Influence of rare earth elements (REEs) on the structure and optical properties of lithium zirconium phosphate (LZP)

Abstract

The objective of presented study was to verify the concept of the formation of the REE–LZP solid solutions according to two different substitution models and to examine optical absorption properties of the samples for pigment application.

Influence of lattice strain on Er3+ ions activated magnesium zirconium phosphate phosphors: Morphological, structural, and photoluminescence properties

“…Also, the lattice strain strongly depends on the Er 3+ ion dopant with an average value of ~ 2.42 × 10 -3 , which is almost identical to the pure/undoped MgZr 4 (PO 4 ) 6 phosphor (2.99 × 10 -3 ). According to Nath et al [13], the slight change in lattice strain is ascribed to the lattice expansion in the crystalline nanopowders as a result of size confinement. On the contrary, doping MgZr 4 (PO 4 ) 6 with Er 3+ ions could initiate atomic rearrangement thus modifies the size confinement as compared to pure MgZr 4 (PO 4 ) 6 and then leads to decrease lattice strain.…”

“…Among various host lattices, magnesium zirconium orthophosphate (MZP) nanophosphor having a NASICON type crystal structure has been found to be an appropriate host material for rare earth ions as well as for application as microwave dielectric materials [14,15] and as solid electrolyte in high temperature electrochemical sensor in non-ferrous scrap metal refining and virgin metal alloying operations [16,17,18]. This host crystal is also suitable for exploiting photoluminescence properties of the Er 3+ -ion dopant due to its properties such as a high phonon energy of 1030 cm − 1 , high refractive index (MgO = 1.735, ZrO 2 = 2.180-2.670, and PO 4 = 1.603), high transmittance at visible-NIR wavelength, and thermal stability [13]. MZP doped with luminescent rare earth such as Er 3+ -ions would be suitable material as a result of an intrinsically faster photoluminescence emission for numerous applications including a scintillator, light emitting diodes, photocatalyst, and biosensing in the visible-NIR wavelength region (400 to 800 nm).…”

“…The MZP phosphor as a host would enable incorporation of a high rare earth ions concentration and solubility along with weak ion-ion interactions to minimise PL and lifetime quenching. Over the years, several methods have been reported for synthesising undoped and rare-earth ions doped alkali metal zirconium phosphate, which include co-precipitation method, solid-state reaction, sol-gel and combustion [4,13,14,15,16]. Adamu et al [14] synthesised MgZr 4 (PO 4 ) 6 nanophosphors using novel and economical sol-gel method at a reduced temperature to investigate the calcination process, and possible phase transformation due to its potential application as a solid state electrochemical sensor in non-ferrous scrap metal refining.…”

“…al. [13] prepared NASICON-like ion conductive rhombohedral rare earth elements doped lithium zirconium phosphate utilising two different synthesis approaches including polymerizable-complex Pechini method and a solid state reaction. They examined the crystal structure and characteristics of their colour optical properties in the visible spectrum (400 to 700 nm) for pigment application.…”