Preparation and characterization of rare earth orthoborates, LnBO3 (Ln = Tb, La, Pr, Nd, Sm, Eu, Gd, Dy, Y) and LaBO3:Gd, Tb, Eu by metathesis reaction: ESR of LaBO3:Gd and luminescence of LaBO3:Tb, Eu

Highlights: {yields} Orthoborates and their solid solutions were prepared by metathesis reaction. {yields} NaCl (by-product) is the driving force for these metathesis reactions. {yields} Structural refinement for TbBO{sub 3} was carried out. {yields} Spin-Hamiltonian parameters of Gd{sup 3+} were deduced from the ESR spectra of LaBO{sub 3}:Gd. -- Abstract: Lanthanide orthoborates of composition LnBO{sub 3} (Ln = Tb, La, Pr, Nd, Sm, Eu, Gd, Dy, Y) and LaBO{sub 3}:Gd, Tb, Eu have been prepared by metathesis reaction. This method provides a convenient route for the synthesis of orthoborates and its solid solutions at low temperatures. Powder X-ray diffraction and FT-IR spectroscopy were used to characterize these borates. Rare earth borates, (LnBO{sub 3}) are isomorphous with different forms of CaCO{sub 3} depending on the radius of rare earth ion. LaBO{sub 3}, LaBO{sub 3}:Gd, Tb, Eu, PrBO{sub 3}, NdBO{sub 3} crystallized in aragonite structure, SmBO{sub 3} crystallized in H-form and TbBO{sub 3}, EuBO{sub 3}, GdBO{sub 3}, DyBO{sub 3}, YBO{sub 3} crystallized in vaterite structure. The structural analysis of TbBO{sub 3} was carried out. The morphology of these borates was obtained from Scanning electron microscopy. Spin-Hamiltonian parameters for Gd{sup 3+} are deduced from room temperature electron spin resonance spectrum of LaBO{sub 3}:Gd. Themore » luminescence of LaBO{sub 3}:Tb, Eu gave characteristics peaks corresponding to Tb{sup 3+}, Eu{sup 3+} respectively.« less