IMPROVED RADIATION SHIELDING

Abstract

Layered nanolaminates (LNL) containing assembled sheets of 2-dimensional (2D) materials with high atomic numbers (Z). namely of transition metal dichalcogenides. Group III and IV chalcogenides and chalcogenides. which have high radiation shielding properties due to the density of their nucleus.

Claims

1. An X-ray radiation shielding material having a layered nanolaminate structure (nacre like) composed of assembled sheets of lead-free 2-dimensional (2D) materials with single or few atomic layers thickness and atomic number.

2. The X-ray radiation shielding material of claim 1, wherein the layered nanolaminate composite structure has a thickness from 1.0 um to 10.000 um

3. The X-ray radiation shielding material of claim 1, wherein the 2D materials are at least one material selected from the group consisting of made of Transition Metal Dichalcogenides (Ti, V, Zr, Nb, Mo, Hf, Ta, W, Re, Pd. Pt), Group III and IV Chalcogenides (Al, Si, Ga, Ge, In, Sn, Sb, Bi) or Chalcogenides (S, Se, Te).

4. The X-ray radiation shielding material of claim 1, wherein the layered nanolaminate structure is made by one type of 2D material, i.e. a homologous structure.

5. The X-ray radiation shielding material of claim 1, wherein the layered nanolaminate structure is a composite made by two or more 2D materials., i.e. a heterologous structure.

6. The X-ray radiation shielding material of claim 5, wherein the layered nanolaminate composite structure is made by two 2D materials in an alternating layer arrangement.

7. The X-ray radiation shielding material of claim 5, wherein the layered nanolaminate composite structure is made by two 2D materials mixed together.

8. The X-ray radiation shielding material of claim 5, wherein the layered nanolaminate composite heterologous structure is made by at least two 2D materials and organized in an alternating layer arrangement.

9. The X-ray radiation shielding material of claim 5, wherein the layered nanolaminate composite heterostructure is made by more than two 2D materials mixed together

10. The X-ray radiation shielding material of claim 5, combined with at least one of a metal film, polymer, clay or inorganic oxides which are incorporated as one or more layers.

11. The X-ray radiation shielding material of claim 5, wherein the composite structure is made by two 2D materials organized into micro laminated segments of each 2D material composed of layered nanolaminate structures.

12. The X-ray radiation shielding material of claim 11, wherein the micro laminated structures are organized in the subsequent order of each 2D material

13. The X-ray radiation shielding material of claim 11, wherein the micro laminated structures are organized in a random and mixed order of each 2D material

14. The X-ray radiation shielding material of claim 5, wherein the composite heterostructures is made by more than two 2D materials organized into micro laminated segments of each 2D material composed of layered nanolaminate structures.

15. The X-ray radiation shielding material of claim 14, wherein the micro laminated composite heterostructures is organized in the subsequent order of each 2D material.

16. The X-ray radiation shielding material of claim 14, wherein the micro laminated composite heterostructures are organized in a random or mixed order of each 2D material.

17. The X-ray radiation shielding material of claim 11, in combination with at least one other materials such selected from the group of metal films (Tin, Cu, Al, steel, Ni), polymer, clays and inorganic oxides which are incorporated as one or more layers in their structure

18. The X-ray radiation shielding material of claim 1, in combination with incorporated leaded shielding materials such as leaded glass, leaded films, and/or Barium sulphate plasters etc.

19. An ionizing (X-ray, gamma, neutron) radiation shielding material comprising layered nanolaminate structures (nacre like) composed of assembled sheets of lead-free 2-dimensional (2D) materials with single or few atomic layers thickness and atomic number

20. The X-ray radiation shielding material of claim 19, for Neutron radiation shielding nanolaminate structure of 2D materials including graphene, hexagonal boron nitride (hBN) and boron-carbide (BN).

21. The X-ray radiation shielding material of claim 20, wherein the layered nanolaminate composite structure has a thickness from 1.0 um to 10.000 um

22. The X-ray radiation shielding material of claim 20, wherein the layered nanolaminate composite structure is made of graphene and its derivates such Graphene oxide, functionalized graphene and doped graphene

23. The X-ray radiation shielding material of claim 20, wherein the layered nanolaminate composite structure is made of boron-doped graphene

24. The X-ray radiation shielding material of claim 20, wherein the layered nanolaminate composite structure is made of hexagonal boron nitride (hBN)

25. The X-ray radiation shielding material of claim 20, wherein the layered nanolaminate composite structure is made of boron carbide (BC)

26. The X-ray radiation shielding material of claim 20, where layered nanolaminate composite structure is made of a combination of graphene or B-doped graphene and hBN.

27. The X-ray radiation shielding material of claim 20, wherein the layered nanolaminate composite structure is made of a combination of graphene or B doped graphene and boron carbide (BC)

28. The X-ray radiation shielding material of claim 20, wherein layered nanolaminate composite structure is made of a combination of hBN and boron carbide (BC)

29. The X-ray radiation shielding material of claim 20, where layered nanolaminate composite heterostructure is made of a combination of graphene or B-doped graphene, hBN and boron carbide (BC) with equal ratio.

30. The X-ray radiation shielding material of claim 20, wherein the layered nanolaminate composite heterostructure is made of a combination of graphene or B-doped graphene, hBN and boron carbide (BC) with different ratios.

31. The X-ray radiation shielding material of claim 20 combined with polymers such as HDPE, polyesters, epoxy etc

32. The X-ray radiation shielding material of claim 20 combined with other conventional neutron shielding materials.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0045] By way of example only, an embodiment of the invention is described more fully hereafter, with reference to the accompanying drawings, in which:

[0046] FIG. 1 is a schematic representation of an embodiment of the present invention showing the 2D arrangement of material;

[0047] FIG. 2 is a graph showing the increase in attenuation of X-ray energy with reducing the thickness of material;

[0048] FIG. 3 is a graph showing the Raman spectra of bulk and exfoliated MoS.sub.2;

[0049] FIG. 4 is a graph of average MoS.sub.2 particle size distribution (ca 432 nm);

[0050] FIG. 5 is a TEM image of exfoliated MoS.sub.2 (scale bar=10 nm), and inset picture a zoom-in image of six atomic layers of MoS.sub.2 structure;

[0051] FIGS. 6a and 6a is a photograph and SEM image of bulk MoS.sub.2 film;

[0052] FIGS. 7a and 7a is a photograph and SEM image of layered nanolaminated MoS.sub.2 film

[0053] FIG. 8a is a graph of the X-ray transmission of bulk and exfoliated MoS.sub.2 composite films, and the controls (air and membrane) (experimental data is extremely reproducible with a standard deviation?0.001%);

[0054] FIG. 8b is an-ray transmission of the exfoliated MoS.sub.2 composite compared with increasing total composite film thicknesses;

[0055] FIG. 9 is an image of MXene film, SEM and TEM images as well as an Energy-dispersive spectrum (EDS) of the graph of the MXene film;

[0056] FIG. 10 is a graph showing X-ray transmission (%) of Mxene film A, B, C and D at different thicknesses (40-180 ?m) performed using 30 KV X-ray energy using thickness 500 um and 1000 um showing shielding attenuation below 10%;

[0057] FIG. 11 is a schematic representation of the synthesis and film preparation, a) mechanical exfoliation of bulk antimony (Sb) combining wet-ball milling and ultrasonication in isopropanol/water (4:1) medium, b) conventional composite structure of X-ray shielding, c) sandwiched laminated approach of shielding;

[0058] FIG. 12 shows the structural and chemical properties of exfoliated FL-Sb. a) SEM micrograph of FL-Sb, b) particle size distribution (Inset image-dispersed FL-Sb in Isopropanol), c) high-resolution TEM image of FL-Sb, d) AFM of FL-Sb, e) line profile showing thickness of the FL-Sb, f) EDS spectrum of FL-Sb, g) X-ray diffraction pattern of FL-Sb, h) Raman spectrum of FL-Sb, i) TGA of FL-Sb;

DETAILED DESCRIPTION OF THE INVENTION

[0059] The present invention is based on the discovery that 2D materials with single or few atomic layer structures organized with nano-layered architecture with nanogaps can provide a structural modes of the radiation attenuation with additional scattering or absorption of photons, electrons and neutrons. This finding has not previously been observed and has not occurred in bulk structures where shielding is defined by Z number, density and materials thickness. The invention is to build on the synergetic combinations of structural properties of single atomic 2D sheets of 2D materials, their high surface area to the volume aspect ratio, and their nano-layered organization of the films with radiation absorption directed by z number that will provide a cascade of scattering/absorption events in interaction with electromagnetic waves, which is not possible with continuous bulk materials. An embodiment of the present invention is shown schematically in FIG. 1 with the scattering of X-ray over a series of 4 separate layers in the 2D arrangement. FIG. 2 shows the change in attenuation over a change in thickness of the material.

Materials and methods

Materials

[0060] Molybdenum disulphide powder (MoS.sub.2, 99.99%, 23 ?m) and sodium bromide (NaBr) was purchased from Chem-Supply (Australia). Carboxymethylcellulose sodium salt (CMC, high viscosity) was provided by Aldrich Sigma (Australia). Hydrophilic PTFE membrane filter (pore size: 0.45 ?m, diameter: 47 mm, thickness: 25 ?m) was purchased from Filter-Bio (China).

Experiments

Exfoliation of MoS.SUB.2 .via Ball Milling

[0061] Bulk MoS.sub.2 powder was exfoliated using a Planetary Ball Mill PM 200 (Retsch, Australia) with zirconium balls (3 mm in diameter). NaBr was added to facilitate the process of the ball milling with a weight ratio of NaBr: MoS.sub.2 at 20:1, and the weight ratio of balls to powder was also 20:1. After the dry ball milling process, NaBr in the as-prepared mixture was washed several times with distilled (DI) water with the aid of a centrifuge (Sigma, Australia, 4200 rpm) and then dried in an oven at 50? C. overnight.

MoS.SUB.2 .Composite Films Preparation

[0062] Bulk and ball-milled (exfoliated) MoS.sub.2 were dispersed with deionised (DI) water and then bath-sonicated for 1 h, respectively. CMC solution (0.5 wt. %) was added to the as-prepared MoS.sub.2 solution with the optimized weight ratio. The mixture was then stirred constantly for 3 h and followed by vacuum filtration onto the membrane, and the composite film was then dried for 12 h in air at the ambient environment (24? C.).

Characterization on MoS.SUB.2 .Composite Films

[0063] The synthesized MoS.sub.2 composite films were characterized by a scanning electron microscopy (SEM, FEI Quanta 450, USA) for surface morphology, and composite thickness. SEM was also performed in backscattered electron (BSE) mode to evaluate the homogeneity of the composite material at an accelerating voltage of 10 kV. X-ray diffractometer (XRD, Rigaku Miniflex 600, Japan) for the measurements of the crystalline forms in the composites were collected in the range of 2?=20-80? (scan rate of 10? C. min.sup.?1). The vibrational characterization and layer identification of bulk and exfoliated MoS.sub.2 were analyzed by Raman spectroscopy (LabRAM HR Evolution, Horiba Jvon Yvon Technology, Japan) using 532 nm laser as the excitation source in the range of 300-500 cm.sup.?1. A 50? objective was used with the laser powder kept at 100%, and all spectra were collected using an acquisition time of 1 s for 3 accumulations. The total composite film thickness (t.sub.CompM) was calculated as equation (1),

[00001]$\begin{array}{cc}{t}_{\mathrm{CompM}}=t_{\mathrm{Comp}}+t_M& \left(1\right)\end{array}$

[0064] Where t.sub.Comp is the composite thickness and t.sub.M is the membrane thickness given as 25 ?m.

X-Ray Attenuation Testing

[0065] X-ray attenuation is the reduction of the intensity of X-ray when it travels through matter (Viegas et al., 2017). The attenuation properties of the controls (air and membrane) and as-prepared MoS.sub.2 composite samples were measured using a Gulmay D3150 superficial X-ray (SXR) unit. The distances between the X-ray tube and the material sample, and the material sample to the detector were both set to 50 cm. The detector used to measure the transmission was a NE 2571 farmer type ionization chamber (Phoenix Dosimetry Ltd, UK). The samples were exposed to the X-ray voltage at 30 kVp (0.20 mm A1 HVL) for 0.50 mins with the material sample placed over a collimator of diameter 1 cm. The X-ray transmission was calculated as the charge collected by the ionization chamber with the sample divided by the transmission dose without the sample. Each sample was measured three times and determined by the arithmetic mean.

[0066] The X-ray attenuation of an X-ray beam through any material can be estimated as a function of the linear attenuation coefficient (?) as equation (2),

[00002]$\begin{array}{cc}I=I_0{e}^{-ut}& \left(2\right)\end{array}$

[0067] Where I and I.sub.0 are the final X-ray intensity after the attenuation by the sample and the X-ray intensity before passing through the sample, respectively, and t is the material thickness (mm). The X-ray transmission (T) can be expressed as equation (3),

[00003]$\begin{array}{cc}T=\left(I/I_0\right)?100\%& \left(3\right)\end{array}$

Characterization of Exfoliated MoS.SUB.2 .and MoS.SUB.2 .Composite Films

[0068] Facile and effective ball-milling methods exfoliate a large quantity of MoS.sub.2 into small layered sheets in FIG. 2(a). SEM image in FIG. 2(b) showed that the large layered MoS.sub.2 sheets with a particle size of 23 ?m were exfoliated into the small and irregular sheets (FIG. 2(c)). EDX analysis was performed to evaluate whether additional elements were generated during ball-milling procedure. The elemental composition of both bulk and exfoliated MoS.sub.2 indicated only the presence of Mo and S as major elements, there was no other additional alteration occurred after ball milling.

[0069] XRD is used to provide the evidence of phase identification for crystalline materials. A typical peak for MoS.sub.2 at 2?=14.9? and a decrease in intensity with an increase in width of the peak represented successfully exfoliated MoS.sub.2 via ball milling. FTIR spectra indicated that a characteristic peak at 470 cm.sup.?1 was detected in both bulk and exfoliated MoS.sub.2, a decreasing intensity of this peak in the exfoliated MoS.sub.2 could be contributed to the smaller thickness after ball milling.

[0070] Raman spectrum of bulk and exfoliated MoS.sub.2 are shown in FIG. 3, indicating that bulk MoS.sub.3 was successfully converted to exfoliated MoS.sub.2, where the typical A.sub.1g and E.sup.1.sub.2g peaks of exfoliated MoS.sub.2 were significantly weakened and blue-shifted by 2.45 cm.sup.?1 relative to those of bulk MoS.sub.2, due to the thickness and lateral size reduction. The frequency difference (??) between A.sub.1g (401.20 cm.sup.?1) and E.sup.1.sub.2g (376.60 cm.sup.?1) of exfoliation MoS.sub.2 was 24.60 cm.sup.?1, which was applied to the identification of the layer number (N) as shown in equation (4),

[00004]$\begin{array}{cc}??\left(A_{1g}-E_{2g}^1\right)=25.8-8.4/N& \left(4\right)\end{array}$

[0071] The calculated N of exfoliated MoS.sub.2 was reduced to 7 layers, evidence of the successful delamination of the bulk MoS.sub.2, which was supported by the particle size reduced to 432.10 nm in FIG. 4 and confirmed by TEM image in FIG. 5 as 6 layers

[0072] FIGS. 6a and 7a show the photographs of bulk and exfoliated MoS.sub.2 composite films along with their SEM images (FIGS. 6b and 7b) of corresponding to their thicknesses. The thickness of bulk MoS.sub.2 composite film was 111.05 ?m, by adding the same amount of exfoliated MoS.sub.2, the thickness of the composite film decreased to 87.07 ?m in FIG. 5(a, b), it was due to the fact that the micro-sized MoS.sub.2 sheets could not provide a dense and smooth coverage and also increase the voltage of the film.

X-Ray Attenuation Measurements

[0073] FIG. 8a shows the X-ray attenuation performance of the as-prepared MoS.sub.2 composites compared to the controls (air and membrane). The membrane did show a slight decrease in the X-ray transmission but only by 1.20%; while it is negligible, there still is a small effect on the X-ray shielding. Comparing with bulk and exfoliated MoS.sub.2 composites, it clearly illustrated that by decreasing the particle size of MoS.sub.2 from 23 ?m to 432.10 nm, there was a significant decrease on X-ray transmission from bulk MoS.sub.2 composite (64.10%) to the exfoliated one (55.96%), indicating that exfoliated MoS.sub.2 composite film presented more effective X-ray shielding ability with a less thickness (87.07 ?m) compared to its bulk material.

Material Thickness

[0074] The photon intensity of X-ray can be reduced by absorption or scattering by several factors, and thickness is one of important factors in radiation shielding application. FIG. 8b shows that by increasing the thickness of the exfoliated MoS.sub.2 composite films from 0.11 mm to 1.34 mm this could attenuate X-ray transmission down to 0.09%, which was similar to X-ray transmission of 0.20 mm Pb (0.10%) calculated by XCOM. Although the optimized thickness (1.34 mm) was thicker than the 0.20 mm Pb-equivalent materials used for X-ray protection garments, the weight of optimized exfoliated MoS.sub.2 composite films (minus the membranes) at 1.18 g was half lighter than the 0.20 mm Pb (2.17 g).

MXene Preparation

[0075] The synthesis steps of MXene materials mainly followed a literature guideline [13]. Briefly, the small pieces of Ti.sub.3AlC.sub.2 max phase were ground into fine powders using a mortar, and the powders having a particle size of less than 25 ?m were selected by a 25 ?m sieve and collected for further use. Lithium fluoride (1.5 g) was added to 20 ml of 9M HCl solution in a reaction vessel under and stirred with a magnetic bar, then 1 gram of Ti.sub.3AlC.sub.2 was slowly added into the solution. The mixture was maintained in an oil bath environment at 35? C. for 24 h. After the etching reaction was completed, the reacted mixture was subjected to centrifugal washing with deionised H.sub.2O at 3,500 rpm for 30 minutes. This washing procedure was repeated 5 to 6 times until the pH value reached around 6, and a relatively pure Ti.sub.3C.sub.2T.sub.x product (MXene) was obtained.

[0076] After washing, the product was ultrasonically separated to obtain a two-dimensional layered MXene material. A small amount of MXene powder was obtained by drying the raw MXene material, and its electrical conductivity was tested. The resulting product was subjected to characterisation measurements (SEM, XRD and EDS) to observe its structure and predict its properties. This prepared MXene material was stored in the refrigerator and used in the subsequent preparation of conductive films.

Fabrication of MXene Conductive Films

[0077] An appropriate amount of MXene material that was refrigerated was taken out, deionised water was added and sonicated for 1 hour to obtain an MXene suspension. The MXene suspension after sonication was allowed to stand for 2 hours, and the supernatant was taken for further use. Different volumes (2 ml, 5 mL and 8 mL) of as-prepared MXene solutions were slowly filtrated by a vacuum filtration system to form conductive films on the membranes. The MXene-deposited membrane connected to the suction filter was placed in a vacuum drying oven and dried at 40? C. for 12 h. After that, the entire system was taken out from the vacuum drying oven, the suction filter was removed, and then the dried MXene conductive film was carefully separated from the membrane. Resistance measurements on samples of different thicknesses were performed on a 4-point multi-height probe system, and the thickness of the films was measured by cross-sectional SEM images.

[0078] As shown above, the use of an embodiment of the present invention in exfoliated MoS.sub.2 composite was applied to X-ray shielding applications. The optimized weight ratio of exfoliated MoS.sub.2 composite with a thickness of 1.34 mm provided effective X-ray shielding performance at the low energy (30 kVp). In addition, the embodiment of the present invention shows that the weight of the exfoliated MoS.sub.2 composite (1.18 g) provided the similar X-ray transmission as 0.20 mm Pb (2.17 g), and both of MoS.sub.2 and CMC are economical and environmentally friendly raw materials, which further enhances the potential use of this novel composite shielding material. This new, lightweight, non-Pb material composite effectively demonstrates its ability as an X-ray shielding alternative to the traditional materials. [0079] A. In some embodiments there is an X-ray radiation shielding material having a layered nanolaminate structure (nacre like) composed of assembled sheets of lead-free 2-dimensional (2D) materials with single or few atomic layers thickness and atomic number. [0080] B. The radiation shielding material of A, wherein the layered nanolaminate composite structure has a thickness from 1.0 um to 10.000 um [0081] C. The X-ray radiation shielding material of claim A or B, wherein the 2D materials are at least one material selected from the group consisting of made of Transition Metal Dichalcogenides (Ti, V, Zr, Nb, Mo, Hf, Ta, W, Re, Pd. Pt), Group III and IV Chalcogenides (Al, Si, Ga, Ge, In, Sn, Sb, Bi) or Chalcogenides (S, Se, Te). [0082] D. The X-ray radiation shielding material of A or B, wherein the layered nanolaminate structure is made by one type of 2D material, i.e. a homologous structure. [0083] E. The X-ray radiation shielding material of A or B, wherein the layered nanolaminate structure is a composite made by two or more 2D materials., i.e. a heterologous structure. [0084] F. The X-ray radiation shielding material of E, wherein the layered nanolaminate composite structure is made by two 2D materials in an alternating layer arrangement. [0085] G. The X-ray radiation shielding material of E, wherein the layered nanolaminate composite structure is made by two 2D materials mixed together. [0086] H. The X-ray radiation shielding material of E, wherein the layered nanolaminate composite heterologous structure is made by at least two 2D materials and organized in an alternating layer arrangement. [0087] I. The X-ray radiation shielding material of E, wherein the layered nanolaminate composite heterostructure is made by more than two 2D materials mixed together [0088] J. The X-ray radiation shielding material of any one of E-H, combined with at least one of a metal film, polymer, clay or inorganic oxides which are incorporated as one or more layers. [0089] K. The X-ray radiation shielding material of claim E, wherein the composite structure is made by two 2D materials organized into micro laminated segments of each 2D material composed of layered nanolaminate structures. [0090] L. The X-ray radiation shielding material of claim K wherein the micro laminated structures are organized in the subsequent order of each 2D material [0091] M. The X-ray radiation shielding material of claim K wherein the micro laminated structures are organized in a random and mixed order of each 2D material [0092] N. The X-ray radiation shielding material of claim E, wherein the composite heterostructures is made by more than two 2D materials organized into micro laminated segments of each 2D material composed of layered nanolaminate structures. [0093] O. The X-ray radiation shielding material of claim N wherein the micro laminated composite heterostructures is organized in the subsequent order of each 2D material. [0094] P. The X-ray radiation shielding material of claim N wherein the micro laminated composite heterostructures are organized in a random or mixed order of each 2D material. [0095] Q. The X-ray radiation shielding material of any one of K-P, in combination with at least one other materials such selected from the group of metal films (Tin, Cu, Al, steel, Ni), polymer, clays and inorganic oxides which are incorporated as one or more layers in their structure [0096] R. The X-ray radiation shielding material of any one of A-Q in combination with incorporated leaded shielding materials such as leaded glass, leaded films, and/or Barium sulphate plasters etc. [0097] S. Ionizing (X-ray, gamma, neutron) radiation shielding material comprising layered nanolaminate structures (nacre like) composed of assembled sheets of lead-free 2-dimensional (2D) materials with single or few atomic layers thickness and atomic number [0098] T. The X-ray radiation shielding material of S for Neutron radiation shielding nanolaminate structure of 2D materials including graphene, hexagonal boron nitride (hBN) and boron-carbide (BN). [0099] U. The X-ray radiation shielding material of T, wherein the layered nanolaminate composite structure has a thickness from 1.0 um to 10.000 um [0100] V. The X-ray radiation shielding material of T and U, wherein the layered nanolaminate composite structure is made of graphene and its derivates such Graphene oxide, functionalized graphene and doped graphene [0101] W. The X-ray radiation shielding material of T and U, wherein the layered nanolaminate composite structure is made of boron-doped graphene [0102] X. The X-ray radiation shielding material of T and U, wherein the layered nanolaminate composite structure is made of hexagonal boron nitride (hBN) [0103] Y. The X-ray radiation shielding material of T and U, wherein the layered nanolaminate composite structure is made of boron carbide (BC) [0104] Z. The X-ray radiation shielding material of T and U where layered nanolaminate composite structure is made of a combination of graphene or B-doped graphene and hBN. [0105] AA. The X-ray radiation shielding material of T and U, wherein the layered nanolaminate composite structure is made of a combination of graphene or B doped graphene and boron carbide (BC) [0106] AB. The X-ray radiation shielding material of T and U, wherein layered nanolaminate composite structure is made of a combination of hBN and boron carbide (BC) [0107] AC. The X-ray radiation shielding material of T and U where layered nanolaminate composite heterostructure is made of a combination of graphene or B-doped graphene, hBN and boron carbide (BC) with equal ratio. [0108] AD. The X-ray radiation shielding material of T and U, wherein the layered nanolaminate composite heterostructure is made of a combination of graphene or B-doped graphene, hBN and boron carbide (BC) with different ratios. [0109] AE. The X-ray radiation shielding material of T and AD combined with polymers such as HDPE, polyesters, epoxy etc [0110] AF. The X-ray radiation shielding material of T and AD combined with other conventional neutron shielding materials

[0111] Although the invention has been herein shown and described in what is conceived to be the most practical and preferred embodiment, it is recognized that departures can be made within the scope of the invention, which is not to be limited to the details described herein but it is to be accorded the full scope of the appended claims so as to embrace any and all equivalent devices and apparatus.