PHOTO-LUMINESCENT MATERIAL OF RARE-EARTH ORTHO-BORATE AND A METHOD FOR PRODUCING THE SAME

摘要

The invention is related to a new compound belonging to the class of luminophors, the family of layered three-cation ortho-borates of general formula ABC(BO)where A, B, C are cations of alkaline, alkali-earth and rare-earth metals. The new photo-luminescent material of formula composition KSrTb(BO)irradiates light in the range of 355 to 620 nm, has a spatial group P2/m of monoclinic crystal system, lattice parameters a=9.298Å, b=5.366Å, c=637Å, β=117.53. During introduction of Sr cation, no reducing atmosphere is required for Tbtransition to Tb. KSrTb(BO)is produced by solid-phase synthesis including preparation of initial mixture of components containing, respectively, % by mass: potassium carbonate KCO- 13.11; strontium carbonate SrCO- 28.00; boric acid HBO- 23.45 and terbium oxide TbO- 35.44, holding at a temperature of 650-700°C during 24 hours, thorough grinding of the sintered product and reheating from 650-700°C to 900-950°C with holding during 8-12 hours.