Use of uranium-containing compound as scintillator

Abstract

The invention discloses use of a uranium-containing compound as a scintillator. The uranium-containing compound is a uranium-containing organic-inorganic hybrid compound or a uranium-containing inorganic compound. The uranium-containing organic-inorganic hybrid compound is a uranium-containing organic carboxylate or a uranium-containing organophosphate. The uranium-containing inorganic compound is a uranium-containing non-metallate, a uranium-containing metal salt, or a uranium-containing halide. The invention discloses the uranium-containing organic-inorganic compound or the uranium-containing inorganic compound having intrinsic scintillating ability, and provides a new concept and method for the development of (organic-inorganic, inorganic) scintillators of various chemical compositions and configurations with the uranium element.

Claims

1. A scintillator comprising a uranium-containing compound, wherein the uranium-containing compound is a uranium-containing organic-inorganic hybrid compound or a uranium-containing inorganic compound, wherein the uranium-containing organic-inorganic hybrid compound is a uranium-containing organic carboxylate of Formula (I) or a uranium-containing organophosphate of Formula (II): ##STR00012## and the uranium-containing inorganic compound is a uranium-containing non-metallate of Formula (III), or a uranium-containing metal salt of Formula (IV): ##STR00013## in which m is 1 or 2, and n is for 2; in Formula (I), R.sup.1 is selected from phenyl, substituted phenyl, or alkyl; in Formula (II), R.sup.2 is selected from phenyl, substituted phenyl or alkyl; in Formula (III), M is selected from the B, N, Si, Se, P, As, S or Te element; in Formula (IV), Y is selected from the Mo, V, Cr, Nb, W, Re, Ga, Ge, Sb or Sn element; and in Formulas (II), (III) and (IV), A.sup.n+ is independently selected from tetramethylammonium cation, Na.sup.+, K.sup.+, NH.sub.4.sup.+, Rb.sup.+, Cs.sup.+, Mg.sup.2+, Ca.sup.2+, Sr.sup.2+, Ba.sup.2+, Pb.sup.2+ or Bi.sup.2+.

2. The scintillator as claimed in claim 1, wherein R.sup.1 is phenyl or alkyl.

3. The scintillator as claimed in claim 2, wherein in Formula (I), the uranium-containing organic carboxylate is UO.sub.2(C.sub.9O.sub.6H.sub.4)(H.sub.2O), and the Formula (I) is a structural formula of: ##STR00014##

4. The scintillator as claimed in claim 3, wherein the UO.sub.2(C.sub.9O.sub.6H.sub.4)(H.sub.2O) is prepared by steps of: dissolving uranyl nitrate, boric acid, and 1, 3, 5-benzenetricarboxylic acid in water, sealing, and performing reaction at 190-250° C., cooling and washing the resulting solution to obtain the UO.sub.2(C.sub.9O.sub.6H.sub.4)(H.sub.2O).

5. The scintillator as claimed in claim 4, wherein a molar ratio of uranyl nitrate, boric acid, and 1, 3, 5-benzenetricarboxylic acid is 0.8-1:1-10:1-2.

6. The scintillator as claimed in claim 1, wherein in Formula (II), n is 1, R.sup.2 is phenyl, and A.sup.n+ is tetramethylammonium cation.

7. The scintillator as claimed in claim 6, wherein in Formula (II), the uranium-containing organophosphate has a structural formula of ##STR00015##

8. The scintillator as claimed in claim 1, wherein in Formula (III), n is 1, M is the B element, and A.sup.n+ is Na.sup.+.

9. The scintillator as claimed in claim 1, wherein in Formula (IV), n is 1, m is 2, Y is the element Mo, and A.sup.n+ is Na.sup.+, Li.sup.+, K.sup.+, Rb.sup.+ or Cs.sup.+; or n is 2, m is 1, Y is the Mo element, and A.sup.n+ is Mg.sup.2+, Ca.sup.2+, Ba.sup.2+, Pb.sup.2+ or Bi.sup.2+.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is a chart showing the radiation resistance vs element density;

(2) FIG. 2 is a schematic view of an X-ray tester;

(3) FIG. 3 shows X-ray fluorescence spectra of different materials;

(4) FIG. 4 shows the relationship between various X-ray powers and the fluorescence intensity of SCU-9;

(5) FIG. 5 shows the comparison of the irradiation stability and the variation trend in the irradiation stability of SCU-9 and CsI:Tl;

(6) FIG. 6 shows the comparison of the humidity stability and the variation trend in the humidity stability of SCU-9 and CsI:Tl; and

(7) FIG. 7 shows the radiation resistance test results of SCU-9 and CsI:Tl within a range of 30 eV-30 keV X-ray energy.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

(8) The invention will be further illustrated in more detail with reference to the accompanying drawings and embodiments. It is noted that, the following embodiments only are intended for purposes of illustration, but are not intended to limit the scope of the present invention.

Embodiment 1

(9) Synthesis of SCU-9 Crystal

(10) The reactants UO.sub.2(NO.sub.3).sub.2.6H.sub.2O, H.sub.3BO.sub.3, and 1,3,5-benzenetricarboxylic acid were placed into a polytetrafluoroethylene reactor at a molar ratio of 1:10:1, a small amount of deionized water was added to dissolve the reactants. The resulting mixture was sealed, heated up to 200° C. and heated for 3 days, and then gradually cooled to room temperature. The product was washed with a large amount of boiling water, until the boric acid was completely dissolved. The resulting crystalline product was washed with ethanol, and then air dried at room temperature, to obtain the SCU-9 crystal. A central metal UO.sub.2.sup.2+ of the crystalline product is coordinated with a carboxylic acid to form a one-dimensional linear polymer with a density of 2.85 g/cm.sup.3.

(11) An X-ray tester was used to test the X-ray fluorescence spectrum of the SCU-9 crystal. The structure of the X-ray tester is shown in FIG. 2. The sample in FIG. 2 is the SCU-9 crystal in this embodiment, and the test result is as shown by an upper curve in FIG. 3.

(12) In addition, the relationship between various X-ray powers and the fluorescence intensity of SCU-9 was tested. CsI:Tl was used as a control. The experimental results show that with the increase of X-ray energy, the fluorescence intensity of the sample also increases correspondingly (FIG. 4b, where the voltage is 40 kV), and the relationship between the two is linear (FIG. 4a), which is consistent with the application characteristic of scintillators.

(13) Luminescence stability under irradiation is another characteristic of the scintillators. FIG. 5a shows the comparison of the irradiation stability of SCU-9 and CsI:Tl, and FIGS. 5b and c show the variation trend in the irradiation stability of SCU-9 and CsI:Tl, respectively. The luminescence output of SCU-9 and CsI:Tl decreases with the increase of doses. The results show that SCU-9 still maintains a 65% luminescence output at a final dose of radiation of 53Gy. Under the same conditions, the luminescence output of CsI:Tl is only about 20%. In order to widen the scope of application, the stability of the scintillator at a high humidity is also a property needed to be determined. The experimental results are shown in FIG. 6. FIG. 6a shows the comparison of the humidity stability of SCU-9 and CsI:Tl. FIGS. 6b and c show the variation trend in the humidity stability of SCU-9 and CsI:Tl respectively. The luminescence output of SCU-9 and CsI:Tl decreases with the increase of the relative humidity. At 95% humidity, the luminescence output of CsI:Tl is decreased to 10% or less, while SCU-9 still maintains about 80% luminescence output.

(14) The radiation resistance of SCU-9 and CsI:Tl within a range of 30 eV-30 keV X-ray energy is calculated. As shown in FIG. 7, at 20 KeV or higher, the SCU-9 compound has a stronger radiation resistance than the commercial product CsI:Tl.

Embodiment 2

(15) Synthesis of (NaBUO-4)

(16) NaNO.sub.3, H.sub.3BO.sub.3, and UO.sub.2(NO.sub.3).sub.2.6H.sub.2O were placed into a polytetrafluoroethylene reactor at a molar ratio of 3:15:1, a small amount of deionized water was added to dissolve the above reactants. The resulting mixture was sealed, heated up to 190° C. and heated for 1 day, and then gradually cooled to room temperature. The product was washed with a large amount of boiling water, until the boric acid was completely dissolved. The resulting crystalline product was washed with ethanol, and then air dried at room temperature, to obtain the (NaBUO-4).

(17) Following the method as described in embodiment 1, the X-ray fluorescence spectrum of (NaBUO-4) was obtained. The result is as shown by a lower curve in FIG. 3.

Embodiment 3

(18) An uranium-containing organophosphate of Formula (II) has a structural formula below, which is referred to as ([TMA][(UO.sub.2).sub.2(1,3-pbpH)(1,3-pbpH.sub.2)]) below:

(19) ##STR00008##

(20) The preparation method is as follows.

(21) 1,3-phenylenebis(phosphonic acid) (1,3-bppH.sub.4), tetrabutylammonium hydroxide, and UO.sub.2(NO.sub.3).sub.2.6H.sub.2O were placed into a polytetrafluoroethylene reactor at a molar ratio of 2:2:1, 1 drop of hydrofluoric acid (HF) was added, and 1 mL of deionized water was added to dissolve the reactants. The resulting mixture was sealed, heated up to 200° C. and heated for 3 days, and then gradually cooled to room temperature. The product was washed with water, and then the resulting crystalline product was washed with ethanol, and air dried at room temperature, to obtain the compound [TMA][(UO.sub.2).sub.2(1,3-pbpH)(1,3-pbpH.sub.2)], which can be used as a scintillator.

Embodiment 4

(22) An uranium-containing metal salt of Formula (IV) has a structural formula below, hereafter referred to as Na.sub.2UO.sub.2(MoO.sub.4).sub.2H.sub.2O, wherein n is 1, m is 2, Y is the Mo element, and A.sup.n+ is Na.sup.+:

(23) ##STR00009##

(24) The preparation method is as follows.

(25) Na.sub.2MoO.sub.4 and UO.sub.2(NO.sub.3).sub.2.6H.sub.2O were placed into a polytetrafluoroethylene reactor at a molar ratio of 1:4, a small amount of deionized water was added to dissolve the reactants. The resulting mixture was sealed, heated up to 200° C. and heated for 3 days, and then gradually cooled to room temperature. The product was washed with a large amount of boiling water. The resulting crystalline product was washed with ethanol, and then air dried at room temperature, to obtain the Na.sub.2UO.sub.2(MoO.sub.4).sub.2H.sub.2O. The compound can be used as a scintillator.

Embodiment 5

(26) ##STR00010##

(27) In a compound of Formula (V), X is the Cl element, and B.sup.+ is the structural formula is shown below, and the compound is referred to as [BTA].sub.2[UO.sub.2Cl.sub.4]:

(28) ##STR00011##

(29) The preparation method is as follows.

(30) UO.sub.2(CH.sub.3COOH).sub.2.2H.sub.2O and phenyltriethylammonium hydroxide were placed into a beaker at a molar ratio of 1:2.9, 2 mL of hydrochloric acid was added, then 10 mL of deionized water was added to dissolve the reactants. The resulting mixture was volatilized for 5-7 days at room temperature until crystallization. The product was washed with water. The resulting crystalline product was washed with ethanol, and then air dried at room temperature, to obtain the compound [BTA].sub.2[UO.sub.2Cl.sub.4]. The compound can be used as a scintillator.

(31) The above description is only preferred embodiments of the present invention and not intended to limit the present invention, it should be noted that those of ordinary skill in the art can further make various modifications and variations without departing from the technical principles of the present invention, and these modifications and variations also should be considered to be within the scope of protection of the present invention.