Microwave preparation method of lanthanum-cerium-terbium oxide fluorescent powder

Abstract

The invention discloses a microwave preparation method of lanthanum-cerium-terbium oxide fluorescent powder, which comprises the following steps: taking oxalic acid, oxalate or ammonium bicarbonate asa precipitant; taking water and/or ethanol as a base solution, and adding a surface additive into the base solution; dropwise adding the raw material solution and a precipitant into the base solutionin twice under the action of ultrasonic waves and stirring, and aging, filtering and drying the obtained precipitate to obtain a lanthanum-cerium-terbium co-precipitate; putting the lanthanum-cerium-terbium co-precipitate into a microwave reactor for microwave heating; wherein the microwave power is 1-10 kW, the microwave heating frequency is 433-5900+/-50 MHz, a microwave output mode comprises one or a combination of continuous waves and pulse waves, the working time is 12-60 min, and performing heat preservation for 1-2 h to obtain the lanthanum-cerium-terbium oxide. The lanthanum-cerium-terbium oxide prepared by the method is consistent in particle size and uniform in morphology.

Description

technical field [0001] The invention relates to the field of preparation of rare earth oxides, in particular to a microwave preparation method of fluorescent powder of lanthanum cerium terbium oxide. Background technique [0002] The luminous intensity, luminous efficiency and resolution of the fluorescent material have a great relationship with the morphology of the phosphor powder. The higher the sphericity of the phosphor powder morphology, the better the luminous performance of the phosphor particles. Lanthanum cerium terbium oxide is a main three-color fluorescent material. The traditional preparation method is to form lanthanum cerium terbium oxalate by co-precipitation of lanthanum cerium terbium salt solution and oxalic acid solution, and then use lanthanum cerium terbium oxalate as the precursor Lanthanum cerium terbium oxide is obtained by burning at high temperature for 5-7 hours. In order to control the growth of the crystal form, various additives are added to i...

AI Technical Summary

Problems solved by technology

Lanthanum cerium terbium oxide is a main three-color fluorescent material. The traditional preparation method is to form lanthanum cerium terbium oxalate by co-precipitation of lanthanum cerium terbium salt solution and oxalic acid solution, and then use lanthanum cerium terbium oxalate as the precursor Lanthanum cerium terbium oxide is obtained by burning at high temperature for 5-7 hours. In order to control the growth of the crystal form, various additives are added to it to help control the growth of the crystal form; research shows that lanthanum cerium terbium oxalate The morphology of lanthanum, cerium and terbium oxides has a great influence on the morphology of lanthanum, cerium and terbium oxides; at the same time, high-temperature solid-phase methods are often used for preparation. When burning at high temperatures, the heat transfer is from the surface to the inside, which is easy to cause The grain size of crystal growth is poor, the morphology is difficult to control, and it is difficult to obtain products with uniform composition

At present, most of the lanthanum, cerium and terbium oxides sold on the market are hexagonal columnar particles, with different particle sizes, uneven shapes, and too many gaps, resulting in poor luminous efficiency and poor performance.

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