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Abstract

In this study, the structural, optical, and radiation shielding characteristics of a PVA/PVP blend loaded with varying ratios (0%, 1%, 2%, and 3 wt%) of Cr₂O₃ nanoparticles (NPs) are studied. This research is driven by the increasing demand for lightweight, flexible, and transparent shielding materials as alternatives to traditional, heavy, and hazardous substances such as lead. This study’s novelty arises in establishing a thorough correlation between the microstructural modifications induced by Cr₂O₃ NPs and their subsequent optical and theoretically assessed radiation shielding features. The X-ray diffraction (XRD) analysis of the produced Cr₂O₃ NPs revealed a crystallite size of 42 nm. The optical band gap value of the PVA/PVP mix was 3.51 eV, which decreased to 1.97 eV with the incorporation of 3% wt. of Cr₂O₃ NPs. The PVA/PVP mix shows an Urbach energy value of 1.42 eV, which incrementally increases to 3.98 eV when the concentration of Cr₂O₃ NPs in the PVA/PVP blend escalates from 0 to 3% by weight. The impact of Cr₂O₃ NPs concentration on the radiation shielding characteristics of PVA/PVP/Cr₂O₃ nanocomposites has been theoretically assessed using the Phy-X tool and the XCOM database. The HVL value varied from 0.475 cm to 29.137 cm for PVA/PVP at 0.015 MeV and 15 MeV, respectively. At the same time, the HVL value ranged from 0.259 cm to 28.161 cm for the PVA/PVP/3%Cr₂O₃ nanocomposites at 0.015 MeV and 15 MeV, respectively. The exposure buildup factor (EBF) of PVA/PVP/Cr₂O₃ nanocomposites has been analyzed as a function of photon energy. Furthermore, the equivalent atomic number (Zeq) values for PVA/PVP/Cr₂O₃ nanocomposites have been studied. The optical features and radiation shielding performance of PVA/PVP/Cr₂O₃ nanocomposites make them suitable for radiation shielding applications.

Keywords

PVA/PVP optical features radiation shielding

Introduction

Researchers have been interested in wide-band-gap semiconductors for decades due to their potential uses in electrical and optoelectronic devices as well as their unexpected properties.¹ Nanostructures of semiconductor metal oxides are intriguing to nanoscience and nanotechnology despite their unusual structural geometry, due to their frequently exhibiting unique characteristics compared to their coarse-grained counterparts.^1,2 Polymer nanocomposites incorporating diverse additives, including metal oxides, carbon-based nanomaterials, and high-Z metal nanoparticles, have garnered considerable interest for industrial applications due to their enhanced mechanical, electrical, and thermal properties.^3–21 Trivalent chromium oxide (Cr₂O₃) is the most stable among other chromium oxide phases, including hexavalent (CrO₃) and tetravalent (CrO₂).² Cr₂O₃ exhibits antiferromagnetism and possesses a substantial energy gap of up to 3.4 eV, finding utility in several applications, including the production of pigments for ceramics, coatings, paints, and printing.¹ Moreover, it has been examined as a lithium cathode, solar absorber, catalyst, and hydrogen sorbent.^22,23 Additionally, it is utilized in electrohydrogenation, dehydrogenation, dye removal, biomedical applications, and gas sensing.^24–26 Chromium oxide-based polymer nanocomposites, such as nano-Cr₂O₃, are increasingly recognized for their ability to combine the processability and flexibility of polymers with the superior thermal, optical, and dielectric properties of chromium oxide fillers, thereby facilitating the development of materials with multiple applications for advanced technologies. Cr₂O_3-doped polymer blends in flexible electronic and energy-storage devices exhibit enhanced dielectric constant, loss, and AC conductivity with increasing nanoparticle loading and frequency, rendering them suitable for storage capacitors, solid-state semiconductors, and other electrical uses. The integration of Cr₂O₃ nanoparticles into polymers diminishes the optical energy band gap, enhances UV absorption, and modifies refractive index dispersion, facilitating the tuning of optical constants for UV-blocking coatings, optoelectronic components, and photonic devices.^27,28

Polyvinyl alcohol (PVA) is a semicrystalline polymer that provides numerous applications due to the presence of hydroxyl groups and hydrogen bonding. Due to its affinity with biological systems, it can also serve as a medicinal agent. Furthermore, PVA exhibits solubility in organic solvents, hydrophilicity, crystallinity, and self-lubricating characteristics.^29–31

In the same way, polyvinylpyrrolidone (PVP) is readily soluble in water and an environmentally friendly polymer that possesses exceptional properties, including compatibility, a superior dielectric constant, and low environmental impact. The interaction between PVA and PVP occurs through hydrogen bonding between the hydroxyl group of PVA and the carbonyl group of PVP. Minor incorporations of PVP are considered to improve miscibility, strengthen hydrogen-bonding interactions, and promote the uniform dispersion of nanoparticles, whereas larger PVP concentrations can negatively impact the mechanical strength of PVA-based films.³² A consistent distribution of fillers in the polymers would be achieved by merging polymers with nanofillers.^33,34

Many nanocomposites of PVA/PVP with different fillers have been studied, including silicon dioxide, titanium dioxide, zinc oxide, cadmium sulfide, copper oxide, manganese oxide, and magnesium oxide.³⁵ Dhatarwal and Sengwa³¹ have documented the optical characteristics of PVP/PVA/Al₂O₃ nanocomposite films. In our previous work, we prepared PVA/PVP (80/20 wt%) loaded with V₂O₅ NPs for optoelectronics.³⁶

Our review of the relevant literature indicates that no effort has been conducted to investigate the optical characteristics and radiation shielding properties of the PVP/PVA mix loaded with Cr₂O₃ nanoparticles (NPs). Therefore, taking into consideration these facts, the purpose of this paper is to investigate in depth the optical behavior of the PVP/PVA/Cr₂O₃ films with a fixed polymer blend compositional ratio (90/10 wt%) and varying amounts of loaded Cr₂O₃ NPs (0, 1, 2, and 3 wt%) to investigate their potential applications in optoelectronic devices. In addition, the influence of the concentration of Cr₂O₃ NPs on the radiation shielding properties of PVA/PVP/Cr₂O₃ nanocomposites has been theoretically estimated using the Phy-X program and the XCOM database. Additionally, the exposure buildup factor (EBF) and the equivalent atomic number (Zeq) values for PVA/PVP/Cr₂O₃ nanocomposites have been studied.

Experimental

Using the co-precipitation method, we have synthesized pure Cr₂O₃ NPs. Chromium (III) nitrate nonahydrate chemical reagents of 99.9% purity were utilized as Cr precursor. The magnetic stirrer continuously agitated 0.1 M of Cr precursor solution for half an hour. The pH value was subsequently regulated by adding an aqueous ammonia solution dropwise. At a pH of 9, the green precipitates commence to form. The soluble impurities were removed by filtering and washing the precipitates formed with distilled water multiple times. Next, the Cr₂O₃ NPs precipitate was dried at 200°C and annealed at 900°C in a muffle furnace for 3 hours. The PVA/PVP films doped with Cr₂O₃ NPs were prepared according to the steps described in our previous work.³⁶

The mass attenuation coefficient (MAC), the half-value layer (HVL), the tenth-value layer (TVL), the mean free path (MFP), the effective atomic number (Z_eff), and the effective electron density (N_eff) values were calculated according to37–40.

Results and Discussions

Structural Analyses

Figure 1(a) displays the X-ray diffraction patterns (XRD) of the synthesized powder Cr₂O₃ NPs. The appearance of sharp peaks in the Cr₂O₃ pattern corroborates the presence of nanoparticles. The angular positions are 24.4°, 33.63°, 36.15°, 41.1°, 50.22°, 54.8°, 63.3°, and 65.10°corresponding to the planes (012), (104), (110), (113), (024), (116), (214), and (300), correspondingly. The observed peak positions correspond well with JCPDS file number 1308-38-9, indicating rhombohedral lattice planes with parameters a = 4.958 Ǻ and c = 13.594 Ǻ.⁴¹ Figure 1(b) shows EDX spectra of Cr2O3 NPs, which affirmed the presence of Cr and O elements with no foreign elements. Additionally, EDX mapping images confirmed the uniform distribution of Cr and O elements over the sample (Figure 2).

Figure 1.

(a) XRD profile and (b) EDX spectra of Cr₂O₃ NPs.

Figure 2.

EDX mapping images of Cr₂O₃ NPs.

Figure 3 displays XRD patterns of the PVA/PVA pure and PVA/PVP/x wt% Cr₂O₃ (x = 1, 2, and 3). A relatively broad peak at 2θ = 19.26° can be observed, which may be attributed to the amorphous polymer matrix of the PVA/PVP blend.³³ Moreover, the diffraction patterns of PVA/PVP/x wt% Cr₂O₃ (x = 1, 2, and 3). The prepared films exhibit both the diffraction peak of PVA/PVP and the diffraction peaks of Cr₂O₃, which means that characteristic peaks demonstrate that Cr₂O₃ NPs indeed occur in the amorphous phase of PVA/PVP. The figure illustrates that the relative intensity of the peak of PVA/PVP (2θ = 19.26°) diminishes following the incorporation of Cr₂O₃ NPs into a PVA/PVP matrix. At a doping concentration of 1 wt% Cr₂O₃, new peaks at 2θ values of 24.4, 33.6, 36.6, and 54.8° corresponding to the crystal planes (012), (104), (110), and (116) of crystalline Cr₂O₃⁴² begin to emerge with impressive, heightened intensities. The distinctive peaks indicate that Cr₂O₃ NPs are present in the amorphous phase of PVA/PVB. Simultaneously, as the content of Cr₂O₃ NPs rises, the severity of these peaks escalates.

Figure 3.

XRD patterns of PVA/PVP/x wt% Cr₂O₃ (x = 0, 1, 2, and 3).

Additionally, the average grain size of the acquired phase D was estimated by applying Debye–Scherrer’s formula provided below⁴³:

D = K_{s} \times λ_{C u} \times {(F W H M \times \cos θ_{B r a g g})}^{- 1}

(1)where λ_Cu denotes the X-ray wavelength, FWHM denotes the full width at half-maximum intensity of the peak, θ_Bragg represents the Bragg reflection angle, and K_s is a constant that equals

(2 \sqrt{\ln 2 / π})

. The subsequent equation can be employed to determine the micro-strain exerted on the internal matrix of the crystalline lattice in the Cr₂O₃ and PVA/PVP/x wt% Cr₂O₃ (x = 1, 2, and 3), utilizing the computed values of the average crystalline grain size corresponding to each prominent peak in the X-ray diffraction pattern⁴⁴:

ε_{μ} = 0.25 \times F W H M \times \cos θ_{B r a g g}

(2)

Moreover, the pertinent connection is employed to compute the dislocation density of the crystallization phases in the Cr₂O₃ and PVA/PVP/x wt% Cr₂O₃ (x = 1, 2, and 3)⁴⁴:

δ = D^{- 2}

(3)

The values of D,

ε_{μ}

and

δ

are enumerated in Table 1. The reported values of the interplanar spacing d are also in Table 1.⁴¹ The table indicates that the average grain size improves with higher Cr₂O₃ content in the PVA/PVP polymer matrix, while the values of other parameters decrease. This trend suggests that the addition of Cr₂O₃ nanoparticles causes grain growth, likely due to particle agglomeration or enhanced crystallization, which in turn influences the composite’s structural and physical properties.

Table 1.

The crystallite size (D), micro-strain (ε), and dislocation density (δ) of pure Cr₂O₃, and PVA/PVP/x wt% Cr₂O₃ (x = 1, 2, and 3).

Sample	d	D (nm)	ε (×10⁻³)	δ (×10⁻³) lines/nm²
Cr₂O₃	3.626	41.963	0.71	0.57
PVA/PVP/1 wt% Cr₂O₃	2.662	22.84	1.28	1.92
PVA/PVP/2 wt% Cr₂O₃	2.477	33.33	0.88	0.90
PVA/PVP/3 wt% Cr₂O₃	1.670	48.54	0.60	0.42

The augmentation in crystallite size indicates a strengthened contact between the polymer chains and Cr₂O₃ nanoparticles, facilitating the rise of crystallite size, as previously documented.⁴⁵ This signifies an improvement in the interaction between the Cr₂O₃ nanofiller, increasing the size of the Cr₂O₃ nanoparticle coalescence in the polymers. Conversely, this reduces micro-strain and dislocation density within the system as the Cr₂O₃ content escalates.⁴⁵ The structural properties of the obtained films will influences both the optical and radiation shielding properties.

Optical Characteristics

Figure 4 depicts the absorbance spectra of the PVA/PVP/Cr₂O₃ nanocomposites. A markedly reduced absorbance was noticed over the visible spectrum. It is noteworthy that absorbance rises when λ drops and with a boost in the concentration of Cr₂O₃ NPs in PVA/PVP. Increasing the Cr₂O₃ NPs loading produces a gradual redshift in the PVP/PVA/Cr₂O₃ absorption bands, moving the spectral features to longer wavelengths as the concentration rises. This behavior is because of the rising Cr₂O₃ NPs concentrations, which produce more localized energy levels and defects that promote light absorption.³⁶ Multiple investigations identified these shifts in behavior.^46–50 The unpaired electron pairs of oxygen atoms in PVA and the n→π* and π→π* transitions related to the carbonyl group (C = O) in PVP are identified by their UV absorbance behavior, which depends on the wavelength.³⁶

Figure 4.

The absorbance spectra of the PVA/PVP/Cr₂O₃ nanocomposites.

Tauc’s relation can be employed to determine the direct band gap E_g from the absorbance edge, as indicated by the absorption spectra⁵¹:

{(α h ν)}^{s} = A (h ν - E_{g})

(4)

The extrapolation procedure, previously described,^47,52,53 is used to ascertain the Eg values of PVA/PVP/Cr₂O₃ nanocomposites. Figure 5(a) illustrates the ${(α h ν)}^{2}$ plot against hν for PVA/PVP/Cr₂O₃ nanocomposites. The bandgap values for PVA/PVP/Cr₂O₃ films at varied Cr₂O₃ NPs contents are presented in Table 2. The reduction in the optical band gap (Eg) of the PVA/PVP blend from 3.51 eV to 1.97 eV when doped with 3% wt Cr₂O₃ nanoparticles can be ascribed from the construction of chemical bonds between the polymer chains as well as Cr₂O₃, which creates localized states within the band edges. This process effectively narrows the band gap by introducing energy states inside the forbidden gap, facilitating electronic transitions at lower energies. This behavior leads to a diminished value of the available energy transitions.^53–55 Increasing the Cr₂O₃ nanoparticle content, along with the accompanying growth in crystallite size, leads to a noticeable narrowing of the band gap. This occurs because larger crystallites reduce the quantum confinement effect, resulting in a narrower band gap. Additionally, oxygen vacancies and defects created during growth further lower the band gap by introducing localized states.^56,57 According to AlAbdulaal et al.,⁵⁸ the optical bandgap for PVA/PVP/K₂Cr₂O₇ nanocomposites ranged from 5.14 to 2.3 eV as the levels of K₂Cr₂O₇ increased. The produced PVA/PVP/Cr₂O₃ nanocomposites have a significantly reduced and adjustable optical bandgap, making them appropriate for optoelectronics applications. In comparison to the materials listed in Table 3, the bandgap values of our samples fall within a more advantageous region, suggesting high potential for applications that require a low bandgap.

Figure 5.

(a) ${(α h ν)}^{2}$ against hν and (b) $\ln α$ versus $h ν$ of the PVA/PVP/Cr₂O₃ nanocomposites.

Table 2.

Optical band gap and Urbach energy Eu for PVA/PVP/Cr₂O₃ nanocomposites.

Sample	Eg (eV)	Eu (eV)
PVA/PVP	3.51	1.42
PVA/PVP +1%Cr₂O₃	3.32	2.56
PVA/PVP +2%Cr₂O₃	2.70	3.27
PVA/PVP +3%Cr₂O₃	1.97	3.98

Table 3.

optical bandgap of different composites compared to those for PVA/PVP/Cr₂O₃ nanocomposites.

Composites	Bandgap (eV)	Refs.
PVA/PVP/Cr₂O₃	3.51-1.97	This work
PMMA-PEG-SnO₂-SiC	3.95	¹⁵
PEO/SiO₂-SiC	3.3-3.7	¹⁴
PVP-Si₃N₄-TiN	3.1-2.4	¹³
PS/SiO₂–Sb₂O₃	3.6-1.8	¹²
PVA/SiO₂/BaTiO₃	4.4-3.2	¹⁰
PMMA/SiC/CdS	3.82-3.2	⁹
PVA/Cr₂O₃/C₃N₄	5.41- 5.10	²⁸
CMC/PEG/Cr₂O₃/V₂O₅	5.6-4.7	⁷²

Urbach energy Eu refers to the exponential variation in defects in the PVA/PVP/Cr₂O₃ nanocomposites.⁵⁹ The correlation between the photon energy and Urbach energy can be expressed as⁶⁰:

\ln α = {\ln α}_{0} + (h ν / E u)

(5)

Figure 5(b) illustrates the relationship between ln α and hν for the PVA/PVP/Cr₂O₃ nanocomposites. Consequently, the Urbach energy values were calculated and shown in Table 2. The PVP/PVA blend exhibits a Urbach energy value of 1.42 eV, which increases progressively to 3.98 eV when the Cr₂O₃ NPs concentration in the PVP/PVA rises. This result indicates that the energy band gap of PVA/PVP/Cr₂O₃ nanocomposites is marginally reduced, since electronic transitions are notably enhanced by increased structural disorder and the formation of localized states.^31,52

The refractive index (n) and the extinction coefficient (k) are optical features that significantly influence the advantageous technological applications of nanocomposites in optical technology and optoelectronic systems.^31,61,62 The refractive index (n) and the extinction coefficient (k) have been calculated as follows^63–68:

n = \frac{1 + R}{1 - R} + \sqrt{\frac{4 R}{{(1 - R)}^{2}} - k^{2}}

(6)

k = \frac{α λ}{4 π}

(7)

The relation between reflectance (R), refractive index (n), and the extinction coefficient (k) and versus λ plots for the PVA/PVP/Cr₂O₃ nanocomposites is illustrated in Figure 6. Extinction coefficient plots, as shown in Figure 6(a), were remarkably comparable to absorbance curves in outline. Figure 6(b) shows the reflectance (R) spectra for the PVA/PVP/Cr₂O₃ films. Furthermore, as shown in Figure 6(a) and 6(c), the extinction coefficient of the PVA/PVP/Cr₂O₃ films is substantially much less than their refractive indices. It was established that the n values drop with reduced wavelengths.³¹ For other nanocomposites, there is evidence of a change in the relationship between n and λ in the literature.^31,69,70 The results might be interpreted as a variation in the density of the PVA/PVP, resulting in changes in the reflectance points inside the host medium. The interaction between the Cr₂O₃ and the PVA/PVP framework alters the polarization, affecting the refractive index.⁷¹

Figure 6.

The relation between (a) k, (b) R, and (c) n versus λ plots for the PVA/PVP/Cr₂O₃ nanocomposites.

Radiation Shielding

The composites combine Cr₂O₃ NPs in a PVA/PVP matrix, showing an increase in the density of the samples with increasing the ratio of Cr₂O₃ NPs (Table 4).

Table 4.

Chemical composition ratios and density of the PVA/PVP/Cr₂O₃ nanocomposites.

Samples	H	C	O	N	Cr	Density (g/cm³)
PVA/PVP	0.090532	0.5556	0.341266	0.012603		1.298101
PVA/PVP/1%Cr₂O₃	0.089636	0.550099	0.341013	0.012478	0.006774	1.307829
PVA/PVP/2%Cr₂O₃	0.088757	0.544706	0.340766	0.012355	0.013416	1.317510
PVA/PVP/3%Cr₂O₃	0.087895	0.539417	0.340524	0.012236	0.019928	1.327143

Figure 7 exhibits the variation of MAC with gamma energy for the PVA/PVP/Cr₂O₃ nanocomposites. The results show that the MAC in the low energy region is greater than at high energy. The MAC increases with the increase in doping with Cr₂O₃. This is because gamma rays’ interaction with matter depends on their energy and the density of matter, or, in other words, the atomic number of matter. The effect of Cr₂O₃ is apparent in low gamma energy (<0.1 MeV) because the photoelectric absorption process is dominant. The key players for the probability are strongly dependant on the energy of the gamma rays as well as the atomic number. The effect of Cr₂O₃ decreases at intermediate energies (>0.1 MeV) because the effect of the photoelectric absorption procedure is reduced, and the Compton scattering is dominant. Herein, the achived probability related to this process depends weakly on the energy of gamma rays as well as the atomic number. It depends on the electron density, which is proportional to Z/A and nearly constant for the PVA/PVP/Cr₂O₃ nanocomposites. The effect of Cr₂O₃ decreases at high energies, where the pair production is the most dominant interaction process. The probability of pair production varies approximately as the square of the atomic number Z and differs slightly.^73,74 Table S1 shows the mass attenuation coefficient (μ/ρ) (cm²/g) for the PVA/PVP/Cr₂O₃ nanocomposites at various energies.

Figure 7.

The change of mass attenuation coefficient (MAC) for the PVA/PVP/Cr₂O₃ nanocomposites.

Figure 8 shows the variation of LAC for the PVA/PVP/Cr₂O₃ nanocomposites with gamma energy. The LAC shows the same behavior as the MAC. Additionally, the half-value layer (HVL) represents the utmost frequently employed factor for explaining the penetration capability of the various types of radaitions or specific radiations as well as the penetration through specific objects.

Figure 8.

The change of linear attenuation coefficient (LAC) for the PVA/PVP/Cr₂O₃ nanocomposite films.

Figure 9 (a) shows the change in HVL for the PVA/PVP/Cr₂O₃ nanocomposites with photon energy. In this figure, the HVL decreases slightly with an increase in the Cr₂O₃ NPs ratio and increases with an rise in the photon energy. A value of HVL changed from 0.475 cm to 29.137 cm for PVA/PVP at 0.015 MeV and 15 MeV, respectively. The HVL value changed from 0.371 cm to 28.802 cm for the PVA/PVP/1%Cr₂O₃ at 0.015 MeV and 15 MeV, respectively. Also, the HVL value changed from 0.305 cm to 28.478 cm and from 0.259 cm to 28.161 cm for the PVA/PVP/2%Cr₂O₃ and PVA/PVP/3%Cr₂O₃, respectively, at 0.015 MeV and 15 MeV. The change of the tenth value layer (TVL) and mean free path (MFP) for the PVA/PVP/Cr₂O₃ nanocomposites is shown in Figure 9(b) and (c). It should be noted that, the diffences in TVL as well as MFP with the energy has the same trend as that detected for the interpretation of HVL.

Figure 9.

(a) The change of the HVL, (b) TVL, and (c) MFP values for the PVA/PVP/Cr₂O₃ nanocomposites.

Figure 10 illustrates the Z_eff and N_eff variation for the PVA/PVP/Cr₂O₃ nanocomposites with different weight percentages of Cr₂O₃ subjected to gamma-ray radiation. The mass attenuation coefficients of the compound, the elements, and the corresponding proportions significantly influence the variation in Z_eff and N_eff. Therefore, the Z_eff and N_eff escalated with increased Cr₂O₃ into PVA/PVP, indicating a rise in the mass attenuation coefficient. These results validate the radiation-shielding potential of the PVA/PVP/Cr₂O₃ nanocomposites.

Figure 10.

The variation of (a) Z_eff and (b) N_eff for the PVA/PVP/Cr₂O₃ nanocomposites.

Figure 11 illustrates the exposure buildup factor (EBF) of the PVA/PVP/Cr₂O₃ nanocomposites as a function of photon energy and the films’ thickness in mean free path (MFP). The EBFs generally have small values across the higher and lower energies, with a peak appearing at middle energies. Furthermore, due to the predominance of the photoelectric effect (PE) at lower energies, many photons ultimately dissipate or deplete all of their energy. This results in a decrease in the number of photons building up. Compton scattering (CS) is a primary component of intermediate energy levels.⁷⁵

Figure 11.

The exposure buildup factor (EBF) of the PVA/PVP/Cr₂O₃ nanocomposites as a function of photon energy.

The estimated equivalent atomic number (Z_eq) for PVA/PVP/Cr₂O₃ nanocomposites, with differing quantities of Cr₂O₃, was presented in Figure 12. The equivalent atomic number reaches the peak values of PVA/PVP/Cr₂O₃ nanocomposites when the photoelectric effect (PE) predominates.

Figure 12.

The estimated Z_eq of PVA/PVP/Cr₂O₃ nanocomposites.

Conclusion

This work investigates the optical characteristics and radiation shielding properties of a PVP/PVA mixture loaded with varying ratios of Cr₂O₃ nanoparticles (0%, 1%, 2%, and 3%). XRD of the synthesized powder Cr₂O₃ NPs exhibited a crystallite size of 42 nm. The PVA/PVP film’s Eg value was 3.51 eV; with the addition of 3% wt Cr₂O₃ NPs, it was lowered to 1.97 eV. The PVA/PVP blend exhibits an Eu value of 1.42 eV, which increases progressively to 3.98 eV when the Cr₂O₃ NPs concentration in the PVA/PVP rises to 3% wt. In addition, the influence of the concentration of Cr₂O₃ NPs on the radiation shielding properties of PVA/PVP/Cr₂O₃ nanocomposites has been theoretically estimated using the Phy-X program and the XCOM database. The value of HVL changed from 0.475 cm to 29.137 cm for PVA/PVP at 0.015 MeV and 15 MeV, respectively. The HVL value changed from 0.371 cm to 28.802 cm for the PVA/PVP/1%Cr₂O₃ at 0.015 MeV and 15 MeV, respectively. Also, the HVL value changed from 0.305 cm to 28.478 cm and from 0.259 cm to 28.161 cm for the PVA/PVP/2% Cr₂O₃ and PVA/PVP/3%Cr₂O₃, respectively, at 0.015 MeV and 15 MeV. The exposure buildup factor (EBF) of the PVA/PVP/Cr₂O₃ nanocomposites as a function of photon energy has been studied. The equivalent atomic number (Zeq) values for PVA/PVP/Cr₂O₃ nanocomposites have also been estimated. It should be noted that the obtained experimental and theoretical results confirm the ability for employing such materials in various optical applications and applications besides their capability for used them as radiation shielders.

Supplemental Material

Supplemental Material - Correlated structural, optical, and radiation shielding characteristics of PVA/PVP/Cr₂O₃ nanocomposites

Supplemental Material for Correlated structural, optical, and radiation shielding characteristics of PVA/PVP/Cr₂O₃ nanocomposites by B. Alayed, A. Z. Mahmoud, Mohammed O. Alziyadi, Asma Alkabsh, Amani Alruwaili, M. S. Shalaby in Journal of Thermoplastic Composite Materials

Footnotes

Acknowledgements

The authors extend their appreciation to the Deanship of Scientific Research at the Northern Border University, Arar, KSA, for funding this research work through the project number NBU-FFR-2024-885-08.

Author contributions

B. Alayed: Funding, Measurements, review the final version, Amani Alruwaili: measurements, Software, Validation, Writing - review & editing. Mohammed O. Alziyadi: Funding resources, Experimental measurements, Software, Asma Alkabsh: Funding sources, measurements, Software, Mustafa Shalaby: Conceptualization, Methodology, Software, Data curation, Project administration, Writing - original draft, Writing - review & editing.

Declaration of conflicting interests

The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Funding

The authors disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: The Deanship of Scientific Research at the Northern Border University, Arar, KSA, for funding this research work through the project number NBU-FFR-2024-885-08.

Data Availability Statement

All data generated or analysed during this study are included in this published article.*

Supplemental Material

Supplemental material for this article is available online.

References

Sone

Manikandan

Gurib-Fakim

, et al. Single-phase α-Cr2O3 nanoparticles’ green synthesis using Callistemon viminalis’ red flower extract. Green Chem Lett Rev 2016; 9(2): 85–90.

Balouria

Singh

Debnath

, et al. Synthesis and characterization of sol-gel derived Cr2O3 nanoparticles. AIP Conf Proc 2012; 1447(1): 341–342.

Hashim

Ibrahim

Hadi

. Fabrication of PS/Si3N4/SrTiO3 multifunctional nanocomposites and boosting their microstructure and optical and dielectric features for energy storage and nanodielectric applications. J Mater Sci Mater Electron 2025; 36(5): 312.

Obaid

Hashim

Rabee

. Manufacturing and ameliorating the morphological, structural and optical features of PVA-CS/SiO2-TaC futuristic nanostructures for radiation shielding and photonics applications. J Inorg Organomet Polym Mater 2025.

Hashim

Ahmed

Ibrahim

, et al. Ameliorating the features of TiN/SiO2 promising nanoceramic doped optical polymer for multifunctional optoelectronics applications. Silicon 2025; 17(3): 585–598.

Sattar

Hashim

. Quaternary PMMA-PEG/SnO2-SiC nanocomposite films for flexible nanodielectric and energy storage applications. Silicon 2025; 17(7): 1681–1692.

Hashim

Ibrahim

Hadi

. Fabrication of SiC-Al2O3 nanoceramic doped organic polymer for flexible nanoelectronics and optical applications. Silicon 2024; 16(18): 6575–6587.

Hashim

Kareem

Ibrahim

. Production and ameliorating the characteristics of (SiO2-CdS) futuristic nanoceramic doped optical material for flexible nanoelectronics applications. Silicon 2025; 17(3): 517–530.

Hashim

Alshrefi

Abed

, et al. Synthesis and boosting the structural and optical characteristics of PMMA/SiC/CdS hybrid nanomaterials for future optical and nanoelectronics applications. J Inorg Organomet Polym Mater 2024; 34(2): 703–711.

10.

Hashim

Mohammed

Hadi

, et al. Synthesis and augment structural and optical characteristics of PVA/SiO2/BaTiO3 nanostructures films for futuristic optical and nanoelectronics applications. J Inorg Organomet Polym Mater 2024; 34(2): 611–621.

11.

Hashim

Ibrahim

Hadi

. Boosting of morphological, structural and optical characteristics of SiC-NiO inorganic nanomaterials merged organic polymer for optoelectronics applications. J Inorg Organomet Polym Mater 2024; 34(12): 6180–6187.

12.

Abdulsalam

Hashim

Mohammed

. Synthesis and tuning the morphological and optical features of PS/SiO2–Sb2O3 promising hybrid nanomaterials for radiation shielding and futuristic optoelectronics applications. J Mater Sci Mater Electron 2025; 36(8): 480.

13.

Hashim

Ibrahim

Rashid

, et al. Synthesis and augmented morphological and optical properties of Si3N4-TiN inorganic nanostructures doped PVP for promising optoelectronics applications. J Inorg Organomet Polym Mater 2025; 35(2): 827–837.

14.

Abbas

Ibrahim

Hashim

, et al. Ameliorating and tailoring the features of Silica-Silicon Carbide Nanoceramic doped polyethylene oxide for promising optoelectronics applications. Silicon 2025; 17(3): 697–707.

15.

Sattar

Hashim

. Fabrication of PMMA/PEG/SnO2/SiC quaternary multifunctional nanostructures and exploring the microstructure and optical features for radiation attenuation and flexible photonics applications. J Mater Sci Mater Electron 2024; 35(31): 2015.

16.

Abdulsalam

Hashim

Mohammed

. Fabrication and ameliorating the performance of PS/SiO2-Sb2O3 futuristic films for high energy storage capacitors and biomedical applications. Trans Electr Electron Mater 2025; 26(3): 395–404.

17.

Fouad

Ali

El-Sayed Seleman

, et al. Mechanical properties and wear performance of denture base polymethyl methacrylate reinforced with nano Al2O3. J Thermoplast Compos Mater 2024; 37: 08927057241241500.

18.

Shokrieh

Joneidi

Mosalmani

. Characterization and simulation of tensile behavior of graphene/polypropylene nanocomposites using a novel strain-rate-dependent micromechanics model. J Thermoplast Compos Mater 2013; 28(6): 818–834.

19.

Rhalmi

Lahkale

Ben Zarouala

, et al., Enhanced optical, dielectric, and mechanical properties of starch-based nanocomposite films reinforced with layered double hydroxide. J Thermoplast Compos Mater 2024; 38(5):1862-1885.

20.

Al-Shawabkeh

Elimat

Abushgair

. Effect of non-annealed and annealed ZnO on the optical properties of PVC/ZnO nanocomposite films. J Thermoplast Compos Mater 2021; 36(3): 899–915.

21.

Vyshakh

Arun

Sathian

, et al. Effect of boehmite nanoparticles on structural, optical, thermal, mechanical and electrical properties of poly (methyl methacrylate) nanocomposites for flexible optoelectronic devices. J Thermoplast Compos Mater 2023; 36(12): 4927–4944.

22.

Dehno Khalaji

. Cr2O3 nanoparticles: synthesis, characterization, and magnetic properties. Nanochem Res 2020; 5(2): 148–153.

23.

Cui

Xia

Cui

, et al. Novel morphologies and growth mechanism of Cr2O3 oxide formed on stainless steel surface via Nd: YAG pulsed laser oxidation. J Alloys Compd 2015; 635: 101–106.

24.

Khamlich

McCrindle

Nuru

, et al. Annealing effect on the structural and optical properties of Cr/α-Cr2O3 monodispersed particles based solar absorbers. Appl Surf Sci 2013; 265: 745–749.

25.

Khamlich

Nemraoui

Mongwaketsi

, et al. Black Cr/α-Cr2O3 nanoparticles based solar absorbers. Phys B Condens Matter 2012; 407(10): 1509–1512.

26.

Chang

Q-Y

Yin

, et al. Tuning adsorption and catalytic properties of α-Cr2O3 and ZnO in propane dehydrogenation by creating oxygen vacancy and doping single Pt atom: a comparative first-principles Study. Ind Eng Chem Res 2019; 58(24): 10199–10209.

27.

Saraji

Alijani

. A molecularly imprinted polymer on chromium (ΙΙΙ) oxide nanoparticles for spectrofluorometric detection of bisphenol A. Spectrochim Acta Mol Biomol Spectrosc 2021; 255: 119711.

28.

Alshammari

. Synthesis of Cr2O3/C3N4 doped PVA polymer membranes for optoelectronic applications. Polym Test 2024; 141: 108651.

29.

Khairy

Elsaeedy

Mohammed

, et al. Anomalous behaviour of the electrical properties for PVA/TiO2 nanocomposite polymeric films. Polym Bull 2020; 77(12): 6255–6269.

30.

Zhang

Jin

, et al. Controllably degradable transient electronic antennas based on water-soluble PVA/TiO2 films. J Mater Sci 2018; 53(4): 2638–2647.

31.

Dhatarwal

Sengwa

. Investigation on the optical properties of (PVP/PVA)/Al2O3 nanocomposite films for green disposable optoelectronics. Phys B Condens Matter 2021; 613: 412989.

32.

Lewandowska

. The miscibility of poly(vinyl alcohol)/poly(N-vinylpyrrolidone) blends investigated in dilute solutions and solids. Eur Polym J 2005; 41(1): 55–64.

33.

Rajesh

Crasta

Rithin Kumar

, et al. Structural, optical, mechanical and dielectric properties of titanium dioxide doped PVA/PVP nanocomposite. J Polym Res 2019; 26(4): 99.

34.

Jeyabanu

Siva

Nallamuthu

, et al. Investigation of electrochemical studies of magnesium ion conducting poly (vinyl alcohol)–poly (vinyl pyrrolidone) based blend polymers. J Nanosci Nanotechnol 2018; 18(2): 1103–1109.

35.

Siva

Vanitha

Murugan

, et al. Studies on structural and dielectric behaviour of PVA/PVP/SnO nanocomposites. Compos Commun 2021; 23: 100597.

36.

Alziyadi

Alruwaili

Said

AMB

, et al. Investigation of the structural, optical dispersion, and optoelectrical characteristics of PVA/PVP/V2O5 nanocomposites for optoelectronic devices. Appl Phys A 2025; 131(1): 53.

37.

Alruwaili

Shalaby

. The impact of NiWO4 on the enhancement of structural, optical, and radiation shielding properties of PVC nanocomposite films. J Mater Sci Mater Electron 2024; 35(34): 2170.

38.

Aşkın

. Gamma and neutron shielding characterizations of the Ag2O–V2O5–MoO3–TeO2 quaternary tellurite glass system with the Geant4 simulation toolkit and Phy-X software. Ceram Int 2020; 46(5): 6046–6051.

39.

Issa

SAM

Abulyazied

Alrowaily

, et al. Improving the electrical, optical and radiation shielding properties of polyvinyl alcohol yttrium oxide composites. J Rare Earths 2023; 41: 2002–2009.

40.

Elsafi

Almousa

Al-Harbi

, et al. Ecofriendly and radiation shielding properties of newly developed epoxy with waste marble and WO3 nanoparticles. J Mater Res Technol 2023; 22: 269–277.

41.

Bhat

, et al. Chromium oxide nanoparticles as a modifier of carbon paste electrode for cyclic voltametric assessment of paracetamol in medicinal sample. Sci Rep 2025; 15(1): 6651.

42.

Abdullah

Rajab

Al-Abbas

. Structural and optical characterization of Cr2O3 nanostructures: evaluation of its dielectric properties. AIP Adv 2014; 4(2): 027121.

43.

Vorokh

. Scherrer formula: estimation of error in determining small nanoparticle size. Наносистемы: Физика, химия. Nanosystems: Phys Chem Math 2018; 9(3): 364–369.

44.

Alruwaili

Alziyadi

Abdelhaleem

, et al. Enhanced the structural, dielectric constants, and Linear/Non-linear optical properties of PVB/Gd2O3 nanocomposites for flexible optoelectronics. J Inorg Organomet Polym Mater 2025; 35: 6271–6289.

45.

Gupta

Kumar

Roy

, et al. Effects of interfacial interactions and nanoparticle agglomeration on the structural, thermal, optical, and dielectric properties of Polyethylene/Cr2O3 and Polyethylene/Cr2O3/CNTs nanocomposites. J Inorg Organomet Polym Mater 2023; 33(2): 407–423.

46.

Choudhary

Sengwa

. ZnO nanoparticles dispersed PVA–PVP blend matrix based high performance flexible nanodielectrics for multifunctional microelectronic devices. Curr Appl Phys 2018; 18(9): 1041–1058.

47.

Abdel Maksoud

Abdelhaleem

Tawfik

, et al. Gamma radiation-induced synthesis of novel PVA/Ag/CaTiO3 nanocomposite film for flexible optoelectronics. Sci Rep 2023; 13(1): 12385.

48.

Abdel Aziz

Bumajdad

Al Sagheer

, et al. Selective synthesis and characterization of iron oxide nanoparticles via PVA/PVP polymer blend as structure-directing agent. Mater Chem Phys 2020; 249: 122927.

49.

Alharthi

Badawi

. Tailoring the linear and nonlinear optical characteristics of PVA/PVP polymeric blend using Co0.9Cu0.1S nanoparticles for optical and photonic applications. Opt Mater 2022; 127: 112255.

50.

Dhatarwal

Sengwa

. Nanofiller controllable optical parameters and improved thermal properties of (PVP/PEO)/Al2O3 and (PVP/PEO)/SiO2 nanocomposites. Optik 2021; 233: 166594.

51.

Davis

Mott

. Conduction in non-crystalline systems V. Conductivity, optical absorption and photoconductivity in amorphous semiconductors. Philos Mag 1970; 22(179): 0903–0922.

52.

Alziyadi

Alkabsh

Said

BAM

, et al. Structural, linear/non-linear optical, and optoelectrical properties of PVB/Bi2WO6 nanocomposite for industrial applications. J Thermoplast Compos Mater 2024; 38(2): 630–656.

53.

Alshahrani

ElSaeedy

Fares

, et al. The effect of gamma irradiation on structural, optical, and dispersion properties of PVA/Zn0.5Co0.4Ag0.2Fe2O4 nanocomposite films. J Mater Sci Mater Electron 2021; 32(10): 13336–13349.

54.

Devi

Sharma

Rao

VVRN

. Electrical and optical properties of pure and silver nitrate-doped polyvinyl alcohol films. Mater Lett 2002; 56(3): 167–174.

55.

Zidan

. Electron spin resonance and ultraviolet spectral analysis of UV‐irradiated PVA films filled with MnCl2 and CrF3. J Appl Polym Sci 2003; 88(1): 104–111.

56.

Musa

Qamhieh

. Study of optical energy gap and quantum confinement effects in zinc oxide nanoparticles and nanorods. Dig J Nanomater Biostruct 2019; 14(1): 119–125.

57.

Liu

Nie

Xue

, et al. Size effects on structural and optical properties of tin oxide quantum dots with enhanced quantum confinement. J Mater Res Technol 2020; 9(4): 8020–8028.

58.

AlAbdulaal

Almoadi

Yahia

, et al. Effects of potassium dichromate on the structural, linear/nonlinear optical properties of the fabricated PVA/PVP polymeric blends: for optoelectronics. Mater Sci Eng, B 2023; 292: 116364.

59.

Wager

. Real-and reciprocal-space attributes of band tail states. AIP Adv 2017; 7(12): 125321.

60.

Abou Hussein

Abdel Maksoud

Fahim

, et al. Unveiling the gamma irradiation effects on linear and nonlinear optical properties of CeO2–Na2O–SrO–B2O3 glass. Opt Mater 2021; 114: 111007.

61.

Alsaad

Ahmad

Dairy

ARA

, et al. Spectroscopic characterization of optical and thermal properties of (PMMA-PVA) hybrid thin films doped with SiO2 nanoparticles. Results Phys 2020; 19: 103463.

62.

Sengwa

Dhatarwal

. Polymer nanocomposites comprising PMMA matrix and ZnO, SnO2, and TiO2 nanofillers: a comparative study of structural, optical, and dielectric properties for multifunctional technological applications. Opt Mater 2021; 113: 110837.

63.

Taha

. Optical properties of PVC/Al2O3 nanocomposite films. Polym Bull 2019; 76(2): 903–918.

64.

Reyes-Coronado

Ortíz-Solano

Zabala

, et al. Analysis of electromagnetic forces and causality in electron microscopy. Ultramicroscopy 2018; 192: 80–84.

65.

Lee

K-S

T-M

Zhang

X-C

. The measurement of the dielectric and optical properties of nano thin films by THz differential time-domain spectroscopy. Microelectron J 2003; 34(1): 63–69.

66.

Zeyada

EL-Nahass

Elashmawi

, et al. Annealing temperatures induced optical constant variations of methyl violet 2B thin films manufactured by the spin coating technique. J Non-Cryst Solids 2012; 358(3): 625–636.

67.

Sell

Casey

Jr Wecht

. Concentration dependence of the refractive index for n‐and p‐type GaAs between 1.2 and 1.8 eV. J Appl Phys 1974; 45(6): 2650–2657.

68.

El-Ghamaz

El-Sonbati

El-Mogazy

. Effect of γ-radiation on the structural and optical properties of poly (3-allyl-5-[(4-nitrophenyl) diazenyl]-2-thioxothiazolidine-4-one) thin films. J Mol Liq 2017; 248: 556–563.

69.

Soliman

Vshivkov

Elkalashy

. Structural, thermal, and linear optical properties of _{SiO 2} nanoparticles dispersed in polyvinyl alcohol nanocomposite films. Polym Compos 2020; 41(8): 3340–3350.

70.

Aziz

Abdullah

Brza

, et al. Effect of carbon nano-dots (CNDs) on structural and optical properties of PMMA polymer composite. Results Phys 2019; 15: 102776.

71.

El-naggar

Heiba

Kamal

, et al. Optical and dielectric behaviors of polyvinyl chloride incorporated with MgFe2O4/MWCNTs. Diam Relat Mater 2023; 138: 110243.

72.

Alanazi

Alenazi

El Sayed

. Tuning the band gap, optical, mechanical, and electrical features of a bio-blend by Cr2O3/V2O5 nanofillers for optoelectronics and energy applications. Sci Rep 2024; 14(1): 12537.

73.

Effendy

Zaid

Sidek

, et al. Influence of ZnO to the physical, elastic and gamma radiation shielding properties of the tellurite glass system using MCNP-5 simulation code. Radiat Phys Chem 2021; 188: 109665.

74.

Mahmoud

Tashlykov

Sayyed

, et al. The role of cadmium oxides in the enhancement of radiation shielding capacities for alkali borate glasses. Ceram Int 2020; 46(15): 23337–23346.

75.

Kassem

Abdel Maksoud

Ghobashy

, et al. Novel flexible and lead-free gamma radiation shielding nanocomposites based on LDPE/SBR blend and BaWO4/B2O3 heterostructures. Radiat Phys Chem 2023; 209: 110953.

Supplementary Material

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Correlated structural,optical,and radiation shielding characteristics of PVA/PVP/Cr 2 O 3 nanocomposites

Abstract

Keywords

Introduction

Experimental

Results and Discussions

Structural Analyses

Optical Characteristics

Radiation Shielding

Conclusion

Supplemental Material

Supplemental Material - Correlated structural, optical, and radiation shielding characteristics of PVA/PVP/Cr2O3 nanocomposites

Footnotes

Acknowledgements

Author contributions

Declaration of conflicting interests

Funding

Data Availability Statement

Supplemental Material

References

Supplementary Material

Supplemental Material - Correlated structural, optical, and radiation shielding characteristics of PVA/PVP/Cr₂O₃ nanocomposites