Preparation And Properties Of Rare Earth-doped Down Conversion Materials

Rare earth elements have excellent optical properties.Spectrum conversion technology by doping rare earth has been better studied and applied in LED lighting,fluorescent imaging,light conversion film and other aspects.Based on orthogonal experiment design method,neodymium nitrate hexahydrate and hexamethylene tetramine as the raw materials to prepare for rare earth doped downconversion materials.Using the chemical titration to deduce the composition of rare earth doped downconversion material and analyzed it by Fourier Infrared Spectrometer,X ray diffracmeter and thermogravimetric aralyzer-differtial theral analy.These are designed to achieve the spectrum inversion from visible area to near-infrared area by the pyrotechnic formular of rare earth doped down-conversion materials.The best preparation process was confirmed.Using neodymium nitrate hexahydrate and hexamethylene tetramine molar ratio 1:2,agitation speed 260r/min,reaction time 80 min and temperature 30 ? successfully prepared with the rare earth doped downconversion material with productivity 75.54%.Based on chemistry results,laws of conservation of mass and charge obtained that rare earth doped downconversion materials contain neodymium ion 22.33%,hexamethylene tetramine 42.64%,nitrate 19.04%,hydroxide 2.71% and hydrone 13.27%,which molar ratio is approximately equal to 1:2:2:1:5.Analysis results of FT-IR,XRD and TG-DTA further confirms Chemical formula is Nd·(C₆H₁₂N₄)2·?NO₃^-?₂·?OH^-?·5H₂O.Pyrotechnic with different oxygen balance radiation intensity tests at 350nm¹050nm show that with 10% rare earth doped downconversion materials pyrotechnics radiation energy 71.82% higher than without at 760nm¹050nm.Combustion spectrum test with 5%,10%,15% rare earth doped downconversion materials pyrotechnics at 500nm⁹00nm show that the percentage of the total radiation energy of pyrotechnic with rare earth doped 14.35% higer than without at 760nm⁹00nm.