Preparation of long-lasting phosphorescent materials through combustion method

The experiment of preparing long-lasting phosphorescent materials through the combustion method
Experimental Objectives: 1. Learn to rapidly synthesize long-lasting luminescence materials using the combustion method. 2. Understand long-lasting luminescence materials and their long-lasting luminescence principles. 3. Learn the basic methods for rapidly synthesizing inorganic oxides and nanomaterials using the combustion method.
The synthesis method of long-lasting glow materials and the relevant experimental steps for synthesizing them using the combustion method
Experimental principle:
The combustion method is also known as self-propagating high-temperature synthesis method. It is a high-heat chemical system that, after being triggered by external energy to undergo local chemical ignition, forms a leading combustion wave, allowing the chemical reaction to continuously spread until the entire system reacts.
This experiment is carried out by using a mixed system of metal nitrates and organic dyes. By dissolving them in a solvent to form a solution and achieving uniform mixing, high-temperature combustion is used to synthesize aluminates. The metal nitrates undergo boiling, concentration, smoke emission, and ignition at high temperatures, and then quickly burn in the form of a combustion wave, maintaining and spreading itself, resulting in a foamy powder. 2Al(NO3)3 + Sr(NO3)2 +20/3CO(NH2)2 + 10O2 -——SrAl2O4 + 40/3H2O +32/3N2 + 20/3CO2
Experimental equipment and materials:
Main reagents: Eu2O3, Dy2O3, strontium nitrate, aluminum nitrate, urea, boric acid, dilute nitric acid
Equipment and instruments: analytical balance, beaker, glass rod, pipette, muffle furnace, porcelain crucible, fluorescence spectrometer
Experimental steps:
(1) Preparation of precursors: Weigh 0.088 grams of Eu2O3; 0.093 grams of Dy2O3; 2.116 grams of strontium nitrate, 7.5 grams of aluminum nitrate, 15 grams of urea; 0.18 grams of boric acid.
1. Dissolve the rare earth oxides with a certain amount of nitric acid and prepare a nitrate ion solution of rare earth ions A.
2. Dissolve the weighed strontium nitrate, aluminum nitrate, urea, and boric acid with a certain amount of water, and heat under stirring to about 70 degrees Celsius to obtain solution B.
3. In a stirring state, slowly add A to B, maintain heating and stirring for a while to make the system mixed evenly and evaporate some water.
4. Transfer the mixture to a ceramic crucible to obtain the precursor that can be used for combustion.
(2) Combustion synthesis of samples: First, preheat the muffle furnace to about 600 degrees Celsius, then quickly place the previous precursors into it. After a few minutes, you can observe the intense boiling and expansion of the reactants, followed by the spread from top to bottom. After the reaction is complete, take it out, cool it down, and you will obtain a foamy synthetic product – long persistence material.
(3) Characterization: After taking out, load the sample, measure the emission spectrum and absorption spectrum of the sample with a spectrophotometer, obtain the corresponding data, organize them, and through software fitting, obtain the relevant graphs.