Ultraviolet excited or near ultraviolet excited borate fluorescent powder and preparation method thereof

Abstract

The invention discloses ultraviolet excited or near ultraviolet excited borate fluorescent powder and a preparation method thereof. A structural formula of the borate fluorescent powder is Ba(2-x-z)Sr(z)Ca(1-y)(BO3)2:xEu<2+>, yMn<2+>, wherein x, y and z are respectively mol percentages of the Eu<2+>, the Mn<2+> and the Sr<2+> in a compound; x is not less than 0 and not more than 0.15; y is not less than 0 and not more than 0.15; z is not less than 0 and not more than 1.5, and the values of x and y are zero simultaneously. The fluorescent powder disclosed by the invention has the advantages of no sulfur, stable performance, wider excitation spectrum, excitation range of 300-430 nm, transmission wavelength of 400-700 nm and suitability for excitation of ultraviolet excited and near ultraviolet LEDs (Light Emitting Diode); the light color of the fluorescent powder disclosed by the invention is adjustable and can be continuously converted from green light to red light according to needs; and the preparation method disclosed by the invention has the advantages of simplicity, feasibility, easiness for operation, easiness for production, no pollution and low cost.

Description

technical field [0001] The invention belongs to the field of fluorescent powder materials, and in particular relates to a borate fluorescent powder for a light-emitting diode (LED), in particular to a borate fluorescent powder excited by ultraviolet or near ultraviolet rays and a preparation method thereof. Background technique [0002] White LED has the advantages of high luminous efficiency, low power consumption, long service life, green environmental protection, etc., and has broad application prospects and value. At present, white LEDs have been applied in many fields such as liquid crystal display backlights, indicator lights, and general lighting, and have a tendency to replace various bulbs and fluorescent lamps currently used. This new type of green light source will surely become a new generation of lighting source, which has extensive and far-reaching significance for energy saving, environmental protection, and improvement of people's quality of life. [0003] A...

AI Technical Summary

Problems solved by technology

However, the white light obtained by this scheme lacks red components, has a high color temperature (>5500K), and low color rendering (Ra<80)

In addition, because the blue light and red light come from different substrates, the color matching process requires high requirements, and the thermal stability of luminescence is not ideal.

Although the three primary color phosphors (RGB phosphors) that emit red, green, and blue light excited by purple light or ultraviolet light are combined to produce white light, it is expected to obtain high color rendering (Ra>90), but the commonly used red powder is Y 2 o 2 S:Eu 3+ , the green powder is ZnS:Cu + ,Al 3+ , the blue powder is BaMgAl 10 o 17 :Eu 2+ There is a reabsorption problem that leads to a decrease in luminous efficiency, and the adjustment and control of the phosphor powder ratio is not easy to solve, resulting in a reduction in the life of the lumen efficiency of white LED devices and an increase in cost

Images