Technology for enhancing luminous intensity of Gd2O2S: Tb < 3 + > fluorescent material by doping Al < 3 + > / Sc < 3 + >

Abstract

The invention discloses a technology for enhancing the luminous intensity of a Gd2O2S: Tb < 3 + > fluorescent material by doping Al < 3 + > / Sc < 3 + >. According to the technology, the Gd2O2S: Tb < 3 + > fluorescent material is taken as a basis, Al < 3 + > / Sc < 3 + > ions are introduced, the position of Gd < 3 + > is replaced by Al < 3 + > / Sc < 3 + >, the symmetry of a crystal field environment around Tb < 3 + > is changed, the photoluminescence intensity of the fluorescent material is enhanced, and the cathode ray luminous intensity of the fluorescent material is also improved.

Description

Technical Field

[0001] The present invention relates to a method for enhancing Gd2O2S:Tb 3+ The technology of luminous intensity of fluorescent materials can enhance the photoluminescence intensity and cathode ray luminescence intensity of fluorescent materials, and belongs to the field of optoelectronic functional materials. Background Art

[0002] Rare earth doped oxysulfide-based fluorescent material is a kind of luminescent material with excellent performance. Gd2O2S (GOS), as the matrix of luminescent material, has the advantages of excellent luminescent performance, high thermal stability and chemical stability. By doping with rare earth elements, the luminescent efficiency of the material can be significantly improved and the luminescent color can be adjusted to obtain fluorescent materials with high color purity, long fluorescence lifetime and good stability.

[0003] Gd2O2S:Tb 3+ Fluorescent materials are widely used cathode ray luminescent materials, mainly used in photoelectric imaging devices such as low-light image intensifiers, scintillator detectors, and neutron photography technology. They are also key materials for X-ray luminescence and high-energy particle detection. With the development of science and technology, the needs of national defense and military construction, and people's production and life, Gd2O2S:Tb with higher luminescence performance 3+ Fluorescent materials can enhance the imaging performance of various optoelectronic imaging devices and equipment, and have significant value for the development of optoelectronic imaging devices in my country. In 2016, Kh. Rezaee Ebrahim Saraee et al. from the University of Isfahan developed a GOS: Tb, Dy nano-phosphor and prepared it into a fluorescent screen for X-ray imaging applications. 3+ Ion doping, Dy 3+ With Tb 3+ There is energy transfer between them, and the activation of Dy has an effect on Gd2O2S:Tb 3+ The spectral characteristics of the luminescent material have a significant impact, which promotes the improvement of luminescence intensity. In 2020, Wenhua Zhang et al. from Shanghai University of Science and Technology developed a Gd2O2S:Tb 3+ ,Dy 3+ Phosphor, and explored Ta 5+ ions in Gd2O2S:Tb 3+ and Gd2O2S:Tb 3+ ,Dy 3+ The promoting effect of 3+ The co-doping of Dy 3+ and Tb 3+ There is a strong energy transfer between them, which promotes the Gd2O2S:Tb 3+ The luminous intensity is improved. 5+The doping of Gd2O2S:Tb can eliminate some S vacancies. 3+ The luminous intensity of the phosphor increases. In 2010, Fei Wang et al. from Kunming University of Science and Technology and East China University of Science and Technology prepared a GOS: Tb 3+ The phosphor is doped with a certain amount of zinc oxide. 2+ The addition of ions improves the luminescence performance (including brightness and chromatic purity), reduces the lattice size, and simplifies the Gd 3+ Ions and Tb 3+ Ions and Tb 3+ Ions and Tb 3+ Energy transfer between ions enhances Tb 3+ The self-sensitization of ions improves the luminescence performance. At present, there are endless studies on rare earth-doped Gd2O2S-based fluorescent materials at home and abroad. Through different regulation methods and different process optimization methods, the luminescence efficiency of Gd2O2S-based phosphors has been enhanced and the spectrum has been regulated, which has promoted the application and performance improvement of Gd2O2S-based fluorescent materials under X-ray, cathode ray and near-infrared light excitation. However, in the realization of high-resolution, high-sensitivity X-ray imaging and low-light night vision applications, it is still necessary to continuously improve Gd2O2S:Tb 3+ The luminous efficiency and luminous intensity of fluorescent materials. Based on this, the present invention proposes Al 3+ / Sc 3+ Micro-doping enhanced Gd2O2S:Tb 3+ A technique for measuring the luminous intensity of fluorescent materials. Summary of the invention

[0004] In order to improve the Gd2O2S:Tb 3+ The luminescent properties of fluorescent materials are enhanced by the present invention. 3+ Technology for measuring the intensity of photoluminescence and cathodoluminescence of fluorescent materials.

[0005] The present invention uses Gd2O2S:Tb 3+ Phosphor is based on Gd2(SO4)3·8H2O, Gd2O3, Tb4O7, Al2O3, Sc2O3, C powder and Na2CO3 as raw materials, and Al 3+ Sc 3+ ions, with a molar concentration of 0-10%, at 1250-1350°C for 2-3 hours to obtain fluorescent material samples. 3+ Sc 3+ The radius is small and it is easy to penetrate into the lattice. 3+ Sc 3+ Replaced Gd 3+ The position of Tb 3+The symmetry of the surrounding crystal field environment changes, which will reduce the activation agent Tb 3+ The spacing between ions helps to increase the luminescence intensity of the material. 3+ Sc 3+ The incorporation of ions helps to optimize the crystal structure of gadolinium oxysulfide, reduce lattice defects and impurities, and a good crystal structure helps to reduce non-radiative transitions and energy losses, thereby improving the luminous efficiency of the material. The technical effect of the present invention is obvious, greatly improving the Gd2O2S:Tb 3+ Luminescence intensity of fluorescent materials: The advantages of the present invention are twofold: first, the photoluminescence intensity of fluorescent materials is enhanced; second, the cathode ray luminescence intensity of fluorescent materials is increased. BRIEF DESCRIPTION OF THE DRAWINGS

[0006] Figure 1 The Gd2O2S:Tb 3+ ,Al 3+ XRD patterns of fluorescent material samples.

[0007] Figure 2 The present invention Gd2O2S:Tb 3+ ,Al 3+ With Gd2O2S:Tb 3+ Photoluminescence emission spectra of fluorescent materials.

[0008] Figure 3 The present invention Gd2O2S:Tb 3+ ,Al 3+ With Gd2O2S:Tb 3+ Photoluminescence excitation spectrum of fluorescent materials.

[0009] Figure 4 The present invention Gd2O2S:Tb 3+ ,Al 3+ With Gd2O2S:Tb 3+ Emission spectrum of fluorescent material under cathode excitation.

[0010] Figure 5 The present invention Gd2O2S:Tb 3+ ,Sc 3+ With Gd2O2S:Tb 3+ Photoluminescence emission spectra of fluorescent materials.

[0011] Figure 6 The present invention Gd2O2S:Tb 3+ ,Sc 3+ With Gd2O2S:Tb 3+ Photoluminescence excitation spectrum of fluorescent materials.

[0012] Figure 7The present invention Gd2O2S:Tb 3+ ,Sc 3+ With Gd2O2S:Tb 3+ Emission spectrum of fluorescent material under cathode excitation. DETAILED DESCRIPTION

[0013] The specific process of the fluorescent material with excellent luminescence performance in the present invention is described as follows:

[0014] (1) Gd2(SO4)3·8H2O, Gd2O3, Tb4O7, Al2O3, Sc2O3, C powder and Na2CO3 were used as raw materials, wherein Na2CO3 was used as a sintering aid. 2-x-y O2S:xT 3+ ,yAl 3+ The amount of each raw material is calculated according to the stoichiometric ratio, where x is Tb 3+ The doping amount of ions, x is 6at%, y is Al 3+ The doping amount of ions (y=0, 0.01, 0.03, 0.05, 0.07). The content of sintering aid Na2CO3 is 14wt% of the product mass.

[0015] (2) According to the preparation of 5 g sample, the corresponding amount of Gd2(SO4)3·8H2O, Gd2O3, Tb4O7, Al2O3, Sc2O3, C powder and Na2CO3 raw materials were weighed using a precision electronic balance, the weighed raw materials were placed in an agate mortar, ground for 20 to 60 min to mix the raw materials evenly, and then placed in a 25 ml alumina crucible;

[0016] (3) The 25 ml crucible containing the raw materials is placed into a 100 ml crucible, which is then placed into a box-type resistance furnace and heated from room temperature to 1250-1350°C at a heating rate of 5°C / min and kept warm for 2-3 h.

[0017] (4) After sintering, the furnace is cooled, and the sample is taken out and pickled, centrifuged, and dried to obtain Gd2O2S:Tb with excellent luminescence performance. 3+ ,Al 3+ Fluorescent material samples.

[0018] Example 1:

[0019] The present invention Gd2O2S:Tb 3+ ,Al 3+ The preparation method of the fluorescent material, the detailed steps are as follows:

[0020] (1) According to Gd 2-x-y O2S:xT 3+ ,yAl 3+The amount of each raw material is calculated according to the stoichiometric ratio, where x is Tb 3+ The doping amount of ions, x is 6at%, y is Al 3+ The doping amount of ions, y, is 7at%.

[0021] (2) According to the preparation method of 5 g sample, the corresponding amount of Gd2(SO4)3·8H2O, Gd2O3, Tb4O7, Al2O3, C powder and Na2CO3 raw materials were weighed using a precision electronic balance, the weighed raw materials were placed in an agate mortar, ground for 20 to 60 min to mix the raw materials evenly, placed in an alumina crucible, and sent into a box-type resistance furnace for calcination at 1250 to 1350°C and kept warm for 2 to 3 h.

[0022] (3) After sintering, the sample was washed with acid for 2 to 4 times, then washed with anhydrous ethanol for 2 to 4 times, and then dried at 80°C for 6 to 12 hours to obtain Gd2O2S:Tb 3+ ,Al 3+ Fluorescent material samples.

[0023] Figure 1 The prepared Gd2O2S:Tb 3+ ,Al 3+ The XRD pattern of the fluorescent material sample is consistent with the diffraction pattern of the standard card PDF#26-1422, indicating that the Gd2O2S phase was successfully synthesized. 3+ and Al 3+ It successfully entered the Gd2O2S matrix, and the diffraction peak was sharp, the intensity was high, and the crystallinity was good.

[0024] Figure 2 The prepared Gd2O2S:Tb 3+ ,Al 3+ Fluorescent material samples and Gd2O2S:Tb 3+ Photoluminescence emission spectrum of fluorescent materials. At 544nm, the photoluminescence intensity of the sample of the present invention is higher than that of Gd2O2S:Tb 3+ The luminous intensity of the fluorescent material increased by 52%.

[0025] Figure 3 The prepared Gd2O2S:Tb 3+ ,Al 3+ Fluorescent material samples and Gd2O2S:Tb 3+ Photoluminescence excitation spectrum of fluorescent materials.

[0026] Figure 4 The prepared Gd2O2S:Tb 3+ ,Al 3+ Fluorescent material samples and Gd2O2S:Tb 3+The cathode ray luminescence spectrum of the fluorescent material shows that at 544 nm, under the excitation of cathode rays, the luminescence intensity of the sample of the present invention is higher than that of Gd2O2S:Tb 3+ The luminous intensity of the fluorescent material increased by 34.5%.

[0027] Example 2:

[0028] The present invention Gd2O2S:Tb 3+ ,Sc 3+ The preparation method of the fluorescent material, the detailed steps are as follows:

[0029] (1) According to Gd 2-x-y O2S:xT 3+ ,ySc 3+ The amount of each raw material is calculated according to the stoichiometric ratio, where x is Tb 3+ The doping amount of ions, x is 6at%, y is Sc 3+ The doping amount of ions, y, is 5at%.

[0030] (2) According to the preparation method of 5 g sample, the corresponding amount of Gd2(SO4)3·8H2O, Gd2O3, Tb4O7, Sc2O3, C powder and Na2CO3 raw materials were weighed using a precision electronic balance, the weighed raw materials were placed in an agate mortar, ground for 20 to 60 min to mix the raw materials evenly, placed in an alumina crucible, sent into a box-type resistance furnace, and calcined at 1250°C for 2 h.

[0031] (3) After sintering, the sample was washed twice with acid and then twice with anhydrous ethanol, and then dried at 80 °C for 6 h to obtain Gd2O2S:Tb 3+ ,Sc 3+ Fluorescent material samples.

[0032] Figure 5 The prepared Gd2O2S:Tb 3+ ,Sc 3+ Fluorescent material samples and Gd2O2S:Tb 3+ Photoluminescence emission spectrum of fluorescent materials. At 544nm, the photoluminescence intensity of the sample of the present invention is higher than that of Gd2O2S:Tb 3+ The luminous intensity of the fluorescent material increased by 21%.

[0033] Figure 6 The prepared Gd2O2S:Tb 3+ ,Sc 3+ Fluorescent material samples and Gd2O2S:Tb 3+ Photoluminescence excitation spectrum of fluorescent materials.

[0034] Figure 7The prepared Gd2O2S:Tb 3+ ,Sc 3+ Fluorescent material samples and Gd2O2S:Tb 3+ The cathode ray luminescence spectrum of the fluorescent material shows that at 544 nm, under the excitation of cathode rays, the luminescence intensity of the sample of the present invention is higher than that of Gd2O2S:Tb 3+ The luminous intensity of the fluorescent material has been increased by 19%.

Claims

1. An enhanced Gd2O2S:Tb 3+ The technology of luminescence intensity of fluorescent materials is based on Gd2O2S:Tb 3+ Based on fluorescent materials. Introducing Al 3+ / Sc 3+ Ion, Al 3+ The molar concentration of Sc is 0-10%, 3+ The molar concentration is 0 to 10%, thereby enhancing the photoluminescence intensity and cathode ray luminescence intensity of the fluorescent material.

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