A significant role of MoO3 on the optical, thermal, and radiation shielding characteristics of B2O3–P2O5–Li2O glasses

The glass system 42.5P2O5–42.5B2O3–(15-x\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$15-x$$\end{document}) Li2O–x\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$x$$\end{document} MoO3x\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$x$$\end{document} = (0,2.5,5.10and15\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$(0, 2.5,5.10 \;{\text{and}}\;15$$\end{document}), was fabricated using a melt-quenching technique. Optical features are examined depending on measuring the absorption and transmission of the prepared glasses. The energy gap (Eopt\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$E_{{{\text{opt}}}}$$\end{document}), increases from 2.23 to 2.49 e.V. Urbach (Eu\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$E_{u}$$\end{document}), decreases from 0.513 to 0.5 e.V. Basicity, polarizability, electronegativity, and some physical constants are determined. The temperature of the glass transition Tg, increases from 493 to 532 °C, the temperature of onset glass crystallization Tc increases from 493 to 532 °C and the temperature of the crystallization Tp increases from 606 to 636 °C. Radiation shielding properties have been examined by Phy-X / PSD. The impact of adding MoO3 to the glasses on their shielding ability was investigated. The lower value of the (MFP) sample has been detected at a higher MoO3 concentration and it is good radiation attenuation glasses. For radiation protection applications, the investigational glasses had superior characteristics.


Introduction
B 2 O 3 -P 2 O 5 glasses with superior efficiency can be used in a variety of different settings. Borophosphate glasses are appropriate for solid-state batteries and nonlinear optics. Due to its evident advantages, lithium borophosphate is a classical glass that has become recognized in storage batteries. These glasses are used as storage batteries in optical and electronic instruments (Narwal et al. 2019;Khafagy et al. 2008;Albarzan et al. 2021;El-Maaref et al. 2021Shaaban et al. 2020aShaaban et al. , 2020bFayad et al. 2020). The characteristics of the combined glass (B 2 O 3 + P 2 O 5 ) networks vary from those of the single glass B 2 O 3 and P 2 O 5 networks.
Transition metal oxides (TMOs) are a fascinating group of semiconductor materials because of their technological advantages for use in microelectronics and display systems. MoO 3 among (TMOs), due to its excellent use in optical materials and electrochemical devices has received increasing attention in recent years. There is a goal that supports manufacturing these glasses regarding the MoO 3 used in these implementations. Different MoO 3 preparation glasses were developed and investigated in response to this broad range of applications (Raza et al. 2019;Santagneli et al. 2007;Sivakumar et al. 2006;Shaaban et al. 2019Shaaban et al. , 2020cRao et al. 2009;Shaaban and Saddeek 2017).
Due to the existence of MoO 4 and MoO 6 in the glass network, MoO 3 appears as the former non-conventional network. The existence of MoO 3 in glass systems does have a modifier impact on UV spectra (Raza et al. 2019;Santagneli et al. 2007;Sivakumar et al. 2006;Shaaban et al. 2019Shaaban et al. , 2020cRao et al. 2009;Shaaban and Saddeek 2017). There are increasingly diverse technologies for molybdenum borophosphate-based glasses, such as laser host fibers and superconducting switches.
Both scientifically and technologically, the significant advances of alkaline borophosphate glasses are considerable. The existence of PO 4 and BO 4 structural units, this consequence approaches from the structural issues connected with covalent links. B 2 O 3 -P 2 O 5-Li 2 O-MoO 3 glasses system possess spread applications because of their radiation shielding and good FT-IR transmission (Elbers et al. 2005;Tricot et al. 2020;Koudelka and Mošner 2001;Magistris and Chiodelli 1983;Shaaban et al. 2021a;Sayed et al. 2021;Wahab et al. 2021;Møller and Mousseau 2013;Mettler et al. 2008;Tekin et al. 2019a;Nowak et al. 2019;König et al. 2019;Kosaka et al. 2019;Etzel et al. 2018;Chida et al. 2013;Kavaz et al. 2019a;Kalnins et al. 2016). In optoelectronics and radiation shielding, molybdenum lithium borophosphate glasses are very useful. Oxide-based phosphate glasses are important for lasers, solid-state batteries, and radiation shielding, because of their unique chemical, and thermal features. As a result, these glasses examined as a promising material for optoelectronic and shielding requests. The main goal of this article is to assist in the preparation of B 2 O 3 -P 2 O 5 -Li 2 O-MoO 3 glasses and investigate their optical and neutron shielding using Phy-X/PSD (Şakar et al. 2020) properties.

Materials and methodology
The glass system 42.5P 2 O 5 -42.5B 2 O 3 -(15 − x ) Li 2 O-x MoO 3 x = (0, 2.5, 5.10 and 15 ), was fabricated using a melt-quenching technique which is followed by an annealing process. All the glasses were manufactured with chemically pure materials containing a purity of 99%. The starting basic material for P 2 O 5 was pure (NH 4 ) 2 HPO 4 , (Merck). The starting basic material for Li 2 O was pure Li 2 CO 3 (Aldrich). The starting basic material for B 2 O 3 was pure H 3 BO 4 (Merck). As such, MoO 3 (Merck) was presented. To remove NH 3 , H 2 O, and CO 2 , the batches were accurately weighed and placed into platinum crucibles and calcined for 1/2 h at 450 °C. The melting was then continued for 2 h in an electric furnace at 1050 °C. The molten were rotated twice to achieve homogenization. Finally, the molten glass was poured into a stainlesssteel mold that had been preheated to the required dimensions. For annealing, glass samples were set at 350 °C. Table 1 shows the glass composition.
The nature of these glasses was assessed using a Philips X-ray diffractometer (model PW / 1710). The spectrophotometer was used to measure optical spectra of investigated glass system (type JASCO V-670). The thermal investigation was carried out with a DTA-50 (Shimadzu-Japan). Phy-X / PSD can calculate a variety of shielding considerations (Şakar et al. 2020). Electron density (N eff ) was predictable as: . EABF and EBF were predicted using G-P fitting B(E, .

XRD
XRD of a glass system is shown in Fig. 1. It is seen that no discrete lines or sharp peaks indicate a high degree of glassy status, according to XRD. In all the synthesized glasses, there is no intense peak in the XRD pattern, except for a broad hump between angles 25° and 35°, as shown in Fig. 1. The sharp intensity at (30) 2θ values concerning MoO 3 content attributed to a reduction in bond length and a higher coordination number.

Optical spectra
The optical properties of a material determine how it interacts with light. Engineers will be able to choose the right material for their application based on optical features like refractive index, absorption coefficients, polarizability, and metallization, among others.   Figure 5 explores of ( .h ) 1∕2 against photon energy ( h ) to evaluate the indirect E opt from the intercept. E opt increases with increasing MoO 3 , as revealed in Table 2. E u has been calculated ∝ 0 exp h E u , Fig. 6 and Table 2 show that there is an inverse relationship between the values of E opt and E u as shown in Fig. 7. The refractive index was calculated using: n = (1−R) 2 +k 2 (1+R) 2 +k 2 . n is presented in Fig. 8 for fabricated glasses. It has already been stated that density increases, then the refractive index for corresponding glass is rising. As a result, it can be directly compared to R , ρ, and opposite to V m .
Glass polarizability and molar polarization were computed as best as possi- (Dimitrov and Sakka 1996;Dimitrov and Komatsu 2002;Zhao et al. 2007;Duffy 1989;Duffy and Ingram 1992). The optical basicity was connected to ∝ 2− 0 .; Λ = 1.67 1 − 1 Figures 9, 10 and 11 exemplifies the R m , ∝ m and Λ separately. The refractive index is trending in the same direction with MoO 3 content has been reported. The molar refraction R m is linked to the E opt and V m of the glasses by this formula.   Because ∝ • and ∧ have the inverse of (χ), they decrease as Mo + increases. These items are listed in Table 2.
The dispersion E o and E d was calculated as (Wemple and Didomenico 1971;Abdel-Aziz et al. 2001Chiad et al. 2016). The hypothesis designated by n 2 − 1 =    and the static dielectric ∞ = n 2 0 . The oscillator's wavelength (λo) and strength (S o ) were calculated using the following formula . These items are recorded in Table 3.

DTA
The thermal analysis (DTA) of glass samples is demonstrated in Fig. 14. The temperature of the glass transition, Tg, is 493-532 ± 3 °C. The temperature of the glass crystallization T c starts at 537-580 ± 3 °C. The temperature of the glass crystallization T c ends at 606-645 ± 3 °C. According to DTA observations, Tg increases from 493 to 532 °C, Tc increases from 537 to 580 °C and Tp increases from 606 to 645 °C with the increase of MoO 3 content. The transformation of Li-O to Mo-O linkages is significantly associated with this behavior. Thermal stability estimated by ΔT = (Tc − Tg) , weighted thermal stability Hg = ΔT∕Tg and S = T p − T c ΔT∕T g . It observed that all thermal stability of samples improved as MoO 3 . The T g , T c , T p, and thermal stability values are obtainable in Table 4.

Photon shielding features
The level of protection was assessed in this article by increasing MoO 3 at the expense of Li 2 O with the composition 42.5B 2 O 3 -42.5P 2 O 5 -(15 − x) Li 2 O-x MoO 3 , (0 ≤ x ≥ 15) . The  mean free path (MFP) is depicted in Fig. 15. It was stated that as photon energy increases, the values of (MFP) increment. This insight revealed that as the photon's energy increases, it becomes capable of transmitting samples on purpose. Because the lower value of the (MFP) sample has a higher MoO 3 content, good radiation attenuation glasses are available. (El-Sharkawy et al. 2020;El-Rehim et al. 2020;Singh et al. 2007Singh et al. , 2005Mostafa et al. 2013;Waly et al. 2016;Tekin et al. 2019bTekin et al. , 2019cMahmoud et al. 2021;Kavaz et al. 2019b;Alomairy et al. 2021;Alothman et al. 2021;Kaur et al. 2016;Sayyed et al. 2020;Agar et al. 2019;Al-Baradi et al. 2021aShaaban et al. 2021b). Figure 16 demonstrates the (N eff ) of fabricated glasses. It is demonstrated that (N eff ) decreases and then rises as energy increments. This significant decrease is accredited to The ASC of fabricated glasses is presented in Fig. 17. The ASC and ESC values are expected to decrease as energy rates increase. The Compton scattering interaction is responsible for this decline. The C eff of fabricated glasses is depicted in Fig. 18. With the increase in photon energy, it is predicted that C eff will decrease. The impact of pair-creation was reflected in the increase in C eff .
The EBF and EABF of fabricated samples have been characterized by Figs. 19 and 20. EBF and EABF values are determined by the lower energy and concentration of the glasses. At lower energy levels, EBF and EABF values are low, but they rise as energy levels rise. After that, gradually decrease as the energy level rises. So, we can divide the energy scale into three parts low, medium, and high. The first part (low energy): the typical phase is the photoelectric effect, and the relationship is reversed with light, and the glasses will absorb the energy photons. The photons are therefore not allowed processes lead to high accumulation value due to multiple scattering processes. Third parts (high energy): the communal method is pair production. In this process, EBF and, EABF is decreased with energy. Therefore, these data helped in the determination of maximum radiation intensity occur. In this research, the highest radiation occurs on the surface of the glasses. In Fig. 21, fast cross-section neutron removal (FNRCS) is shown. It was stated that MoO3 improved FNRCS.

Conclusions
In the existing research, molybdenum lithium borophosphate glasses 42.5P 2 O 5 -42.5B 2 O 3 -(15 − x) Li 2 O-xMoO 3 where x = (0 ≤ x ≥ 15 ) were fabricated with conventional melt-quenching procedures. Optics, thermal, and shielding factors were observed. The findings showed the following objects: 1. Because of the increase in MoO 3 , the metallization of these glasses was improved. 2. The 2.23 for G 1, 2.32 for G 2, 2.38 for G 3, 2.41 for G 4, and 2.49 for G 5 were identified as the indirect optical bands that were collected. 3. Urbach energies of these samples were reduced as the content of MoO 3 increased. 4. As the density of the investigated samples increments, the refractive index rises as well. 5. These glasses were investigated for molar polarization, polarizability, and optical basicity. 6. T g , T c , T p, and thermal stability values are enhanced with MoO 3 . 7. The fabricated samples' gamma shielding features were predictable. The impact of adding MoO 3 to the glasses on their shielding ability was mentioned. 8. The lower value of the (MFP) sample has more MoO 3 are good radiation attenuation glasses are available. 9. As the concentration of MoO 3 increased, these glasses have a high cross-section neutron removal rate.
The findings discovered that as MoO 3 increases the glass system can result in significant improvements in attenuation and optical characteristics. Furthermore, it is possible to use this glass in optoelectronics, optical devices, and a radiation shield for use in x-ray centers.