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Owing to its wear resistance and mechanical performance, glass-ceramics are often favoured in dental applications. However, prolonged immersion can cause material degradation and reduced strength. Typically, adding fluoride is believed to improve their properties. Hence, this work prepared fluoride-free and fluoride glassceramics via the melt-quenching technique. The samples were assessed after soaking PBS solution for 14 days. The fluoride sample exhibited a higher hardness of HV = 653 ± 2.80 and toughness of 3.37 ± 0.01 MPa⋅m1/2. This experimental results were compared to the human dentine (HV = 61.2), human enamel (HV = 510) and commercial dental glass-ceramics (HV = 408–663). The fluoride samples showed higher bioactivity, evident from the crystal formation in micrographs. Therefore, the prepared samples exhibit a promising potential as new materials for dental crown applications.

In this paper, a series of [Sm2O3]x[(ZnO)0.5 (B2O3)0.1 (SLS)0.4]1-x, where × = 0, 0.01, 0.02, and 0.03 in weight fraction was fabricated via melt-quenching method. The influence of the samarium ion (Sm3+) concentration on the structural and optical properties was investigated. X-ray diffraction (XRD) and Fourier-transform infrared spectroscopy (FTIR) confirmed the samples’ glassy (amorphous) behavior. The optical absorption intensity enhanced as the dopant increased, whereas the optical band gap reduced with the progression of Sm3+ concentration. The sample’s refractive index and Urbach energy range from 2.145 to 2.203 and 0.682 eV to 0.713 eV, respectively. From the photoluminescence studies, 3 wt% Sm3+-doped samples indicate the most intense emission in the orange-reddish region among the other samples. The calculated CIE coordinates for Sm3+ doped ZnO–B2O3–SLS glasses are approximate (0.57, 0.43), near the Amber LED NSPAR 70BS produced by Nichia Corporation. In addition, the CCT of the Sm3+-doped samples at about ~ 1750 K reveals prepared glass samples have bright orange-reddish emission. These findings indicate that Sm3+-doped in ZnO-B2O3-SLS has enhanced its orange-reddish emission and potential as an orange-reddish glass phosphor material in optoelectronic devices such as glass phosphor for LEDs.

In this paper, a series of [Sm2O3]x[(ZnO)0.5 (B2O3)0.1 (SLS)0.4]1-x, where × = 0, 0.01, 0.02, and 0.03 in weight fraction was fabricated via melt-quenching method. The influence of the samarium ion (Sm3+) concentration on the structural and optical properties was investigated. X-ray diffraction (XRD) and Fourier-transform infrared spectroscopy (FTIR) confirmed the samples’ glassy (amorphous) behavior. The optical absorption intensity enhanced as the dopant increased, whereas the optical band gap reduced with the progression of Sm3+ concentration. The sample’s refractive index and Urbach energy range from 2.145 to 2.203 and 0.682 eV to 0.713 eV, respectively. From the photoluminescence studies, 3 wt% Sm3+-doped samples indicate the most intense emission in the orange-reddish region among the other samples. The calculated CIE coordinates for Sm3+ doped ZnO–B2O3–SLS glasses are approximate (0.57, 0.43), near the Amber LED NSPAR 70BS produced by Nichia Corporation. In addition, the CCT of the Sm3+-doped samples at about ~ 1750 K reveals prepared glass samples have bright orange-reddish emission. These findings indicate that Sm3+-doped in ZnO-B2O3-SLS has enhanced its orange-reddish emission and potential as an orange-reddish glass phosphor material in optoelectronic devicessuch as glass phosphor for LEDs.

This work focus on fabrication of new Gd3+-doped willemite (Zn2SiO4) glass-ceramics derived from the Gd2O3–ZnO–Al2O3–B2O3–SiO2 (Gd-ZABS) glass system by a controlled sintering process. The physical characteristic with formation of Gd3+-doped Zn2SiO4 glass-ceramic crystal phase, morphology and structural changes were examined by Archimedes method, X-ray diffraction (XRD), Field Emission Scanning Electron Microscope (FESEM) and Fourier-transform infrared (FTIR) reflection spectroscopy. The appearance of SiO2, ZnO4 and Zn–O–Si bands indicate that the formation of Zn2SiO4 crystal phase. As for elastic analysis, the ultrasonic velocity and elastic coefficients showed an increasing tendency with the increase in sintering temperature. The study on energy transfer has found that the optical band gap of Gd3+-doped Zn2SiO4 glass-ceramic has decreased as the sintering temperature increased. The luminescence spectra of Gd3+-doped Zn2SiO4 exhibit several strong emission peak located at 425, 447, 462, 485 and 530 nm after the samples were subjected to 310 nm excitation source. Prominent green emission of Gd3+-doped Zn2SiO4 glass-ceramic were strongly observed at 530 nm. These spectra show that when the sintering temperature increases, the luminescence performance of the glass-ceramics has improved.

The influence of different Nd2O3 doping contents on the physical and optical properties of the glasses was evaluated. XRD patterns of the as-quenched samples confirmed their glassy nature. Density, ion concentration and field strength increases with the addition of Nd2O3 content, respectively. The absorption spectrum of the glasses exhibit intense peaks at approximately 580, 744 and 800 nm corresponding to the electronic transitions in Nd3+. With increasing Nd2O3 contents, the refractive indices of the glasses were increased from 2.363 to 2.415. FTIR spectra revealed the presence of BO4 and BO3 structural units in the glasses. Emission spectrum of glasses (at 300 nm excitation) displayed four prominent peaks at 368, 421, 483 and 514 nm due to the electronic transition in Nd3+from 4I9/2 to 4P3/2, 2P11/2, 2G11/2, 2G9/2, 4G11/2, and 4G9/2, respectively. The proposed glass system were highly sensitive to the Nd2O3 contents changes.

A series of zinc borosilicate glass doped with dysprosium oxide (Dy-ZBS) has been successfully fabricated through the conventional melt-quench technique with the incorporation of bio-silica source from rice husk ash. The physical, structural, luminescence, and optical properties of the fabricated glass have been studied utilizing the bulk density, x-ray diffraction pattern, photoluminescence emission spectra, chromaticity coordinates, absorption spectra, and optical band gap. The bulk density improved from 3.468 gcm− 3 to 3.635 gcm− 3 as the dopant concentration increased due to the compactness of the network structure. The amorphous nature of the glass has been justified by using an X-ray diffraction pattern. Whereas the photoluminescence emission spectra have been confirmed the presence of blue and yellow colors and were intensified as the Dy3+ increases. The CCT values from chromaticity diagram of the best white light-reaching coordinates are (0.3028, 0.3334) and classified as cool white. The optical absorbance was found to be enhanced as the Dy2O3 raised from 0 wt% to 3 wt%. Meanwhile, both the direct and indirect optical band gaps were decreased consecutively. Thus, this fabricated glass is suggested to be future solid-state light materials as a white light-emitting diode (WLED) light source.

Photopyroelectric (PPE) technique has been widely used in applied science and technology fields including the study of materials in thermal and optical properties. The sample, Zn1-xCox (x= 0.4, 0.8, 1.2, 1.6, 2.0 wt%) was prepared using solid state method sintered at 1200 ͦC to study the effect of concentration on the energy band gap (Eg). XRD, SEM with EDX analysis were used to characterise the materials' structure, morphology, and density. The PPE setup is used to determine band gap energy (Eg) values. The Eg shows the decreasing trend when the concentration of CoO increases

Bioactive glass (BG) is well known as materials that have ability to form hydroxyapatite layer (HA) that accelerates bonding between bone tissues indicating a good biological response. However, previous BG with composition of SiO2-CaO-Na2O-P2O5 system exhibit lower mechanical strength. Current study is to investigate the effect of alumina (Al2O3) in the 44SiO2-(20-x) Na2O-24CaO-6P2O5-6CaF2-xAl2O3 system where x = (0,3,6, and 9 wt%) towards its mechanical performance. Structural and microstructural factor were analyzed by x-ray diffraction (XRD) and scanning electron microscopy (SEM), meanwhile the density of glass ceramic samples was measured by Archimedes’ method. Subsequently, it was found that Al2O3 with higher composition that sintered at 950 °C has excellent results in term of density measurement. XRD analysis also has confirmed the increase of crystallization of anorthite, fluorapatite and nacaphite along with the rise of Al2O3 concentration. SEM analysis at the same time shows the morphology of agglomeration and irregular shape with a variation on size of sintered glass ceramics.

Four series of CaO-ZnO-B2O3-SLS (CZBS) glasses have been synthesized by using waste materials which are eggshell (EG) and soda lime silica (SLS) glass. We utilized eggshells to source calcium oxide (CaO) in this work, whereas we utilized SLS glass to substitute silica. CZBS1, CZBS2, CZBS3 and CZBS4 are the glass series containing weight percentages of CaO (15%, 20%, 25% and 30%) and SLS (70%, 65%, 60% and 55%), respectively, with the addition of 10% of B2O3 and 5% of ZnO in each sample. A conventional melt and quenching method was applied in this work to fabricate the CaO-ZnO-B2O3-SLS glass system. The glass transition temperature (Tg) was determined using differential scanning calorimetry (DSC), which revealed that the Tg increased from 714 to 735 °C, as the CaO content increased. Meanwhile, the glass structural properties were investigated, revealing an amorphous nature with no sharp peak. The experimental elastic moduli obtained by acquiring ultrasonic speeds using the ultrasonic pulse-echo method were compared to the hypothetical elastic moduli obtained by direct estimation of the hypothetical model.

This paper outlines the fabrication of bioactive glass derived from waste eggshells as a source of calcium via the melt and water quenching method. The influence of the CaF2/P2O5 ratio on the physical, structural and mechanical properties of bioglass samples was investigated. XRD confirmed the amorphous structure, while the presence of Si–O–Si, P–O, and C–O indicated the formation of bioglass samples. It was found that increasing CaF2 content with appropriate P2O5 content could improve the mechanical properties of the bioglass. The increase in density can significantly impact the bioglass samples’ compressive strength and vickers microhardness. The bioglass with CaF2/P2O5 ratio of 6/4 possessed better properties, showing the optimal compressive strength (48.98 ± 0.11 MPa) and vickers microhardness (3.09 ± 0.07 GPa), which is compatible with the human enamel and commercial bioglass. Thus, the findings seem to contribute to a prospective cost-effective waste-derived bioglass system used in dental applications.

Samarium (III) oxide doped zinc-borosilicate glasses were successfully fabricated using the melt-quenching method by using SLS glass as a source of SiO2. With the progression of Sm3+ concentration, the density of the sample improved from 3.423 g/cm3 to 3.495 g/cm3, while the molar volume raised from 21.760 cm3/mol to 23.665 cm3/mol. The XRD analysis verified the samples’ amorphous nature. Besides, the longitudinal and shear velocity range between 5265.15 and 5706.244 m/s and 2900.247–3039.522 m/s, respectively. The elastic moduli for longitudinal, shear, bulk, and Young’s modulus range between 96.389–111.457 GPa, 29.247–31.624 GPa, 56.493–69.292 GPa, and 75.000–82.345, respectively. Furthermore, with the increment of Sm3+ concentration, the sample’s Poisson’s ratio reduces from 0.302 to 0.270, indicating a progressive rise in cross-link density due to increased glass ionicity. Moreover, the fractal bond connectivity and fugacity rise from 1.826 to 2.170 and 0.060 to 0.083, respectively, with the progression of Sm3+ concentration. The findings imply that the Sm3+ dopant acts as a glass modifier, impacting the elastic performance of the zinc-borosilicate glasses.

This research reports the optical and luminescence properties of new tellurite glass system with nominal composition of x(Sm2O3)–10MgO–30B2O3−(60−x)TeO2, where x = 0, 0.5, 1.0, 2.0 and 3.0 mol% synthesized via fast cooling melt-quenching method. The physical characteristic, UV–visible, refractive index, and photoluminescence spectroscopy techniques were used to examine the structural changes and optical performance of the glasses. No sharp peak appeared in the diffraction of XRD region proved the amorphous state of the glasses. The bulk density of the prepared glass samples presented an increasing trend from 4.105 to 4.403 g/cm3 meanwhile the molar volume showed opposite pattern with range value of 28.69–29.39 cm3/mol. The highest density governed by glass sample with concentration of samarium ions at 3.0 mol%, which is 4.403 g/cm3. The optical absorption spectra were characterized to determine the energy band gap, Urbach energy, and refractive index of the glasses. The obtained values for refractive index is in between 2.481 and 2.575 meanwhile for Urbach energy is 0.238–0.319 eV. The optical absorption spectra reveal eleven energy transitions bands centered at 4G9/2, 4I11/2, 4F3/2, 4G5/2, 6F11/2, 6F9/2, 6F7/2, 6F5/2, 6F3/2, 6H15/2, 6F1/2 from ground state of 6H5/2. Four strong emission peaks occurred in photoluminescence, with the highest red emission peak at 600 nm. Chromaticity coordinates of the glass samples were determined as well as the dominant wavelength and colour purity, using CIE Chromaticity diagram 1931.

This paper reports on developing low-cost fluoride-containing glass–ceramics derived from eggshells waste as a source of calcium via the conventional melt-quenching method. The physical, structural, and mechanical properties of the samples before and after sintering is highlighted in this study. XRD and FTIR analysis confirmed the presence of fluorapatite, wollastonite, and cuspidine phases. It is worth noting that adding fluoride to the glass system would lead to the improvement of the mechanical properties of the final product. Among all, the sample sintered at 700 °C achieved the highest density and mechanical properties. It obtained a density value of 2.626 g/cm3, a microhardness result of 6.72 GPa, and fracture toughness of 3.55 MPa·m1/2. These results are better than commercial 45S5 bioglass (0.148 GPa–0.375 GPa) and comparable to the properties of human enamel (2.00 GPa–6.00 GPa). These findings would be believed to contribute to a low-cost waste-derived fluoride-containing glass–ceramics system in the dental application.

In this study, a promising relationship between antibacterial zone and radiation attenuation properties was investigated in Ag2O doped bioactive glasses with a chemical composition of xAg2O–20Li2O–25TeO2-(55-x)B2O3 (where x = 0, 0.5, 1.0, 1.5, and 2.0 mol%). For this aim, a wide-ranging radiation attenuation characterization procedure was performed on Ag2O substituted bioactive glasses. The general-purpose Monte Carlo code MCNPX (v.2.7.0) was used to model bioactive glasses. The mass attenuation coefficients were calculated using a gamma-ray transmission setup. The coefficients obtained were used to determine other important attenuation properties. Finally, for particular behaviors, exposure (EBF) and energy absorption (EABF) build-up factors were calculated for specific attitudes of Ag2O substitutions in bioactive glasses during the interaction process. The results showed that there is direct relationship between Ag2O substitution amount and radiation attenuation properties. In addition to its well-behaviors on inhibition zone against bacterial occurrences, it can be concluded that increasing Ag2O would increase the gamma-ray attenuation properties of studied bioactive glass system.

With the trend for green technology, the study focused on utilizing a forgotten herb to produce an eco-friendly coating. Andrographis paniculata or the kalmegh leaves extract (KLE) has been investigated for its abilities in retarding the corrosion process due to its excellent anti-oxidative and antimicrobial properties. Here, KLE was employed as a novel additive in coatings and formulations were made by varying its wt%: 0, 3, 6, 9, and 12. These were applied to stainless steel 316L immersed in seawater for up to 50 days. The samples were characterized and analyzed to measure effectiveness of inhibition of corrosion and microbial growth. The best concentration was revealed to be 6 wt% KLE; it exhibited the highest performance in improving the ionic resistance of the coating and reducing the growth of bacteria.

Arecanut husk (AH) was selected as a material for silica replacement in the synthesis process of glass-ceramics zinc silicate and also the fact that it has no traditional use and often being dumped and results in environmental issues. The process of pyrolysis was carried out at temperature 700 °C and above based on thermogravimetric analysis to produce arecanut husk ash (AHA). The average purity of the silica content in AHA ranged from 29.17% to 45.43%. Furthermore, zinc oxide was introduced to AHA and zinc silicate started to form at sintering temperature 700 °C and showed increased diffraction intensity upon higher sintering temperature of 600 °C to 1000 °C based on X-ray diffraction (XRD) analysis. The grain sizes of the zinc silicate increased from 1011 nm to 3518 nm based on the morphological studies carried out by field emission scanning electron microscopy (FESEM). In addition, the optical band gap of the sample was measured to be in the range from 2.410 eV to 2.697 eV after sintering temperature. From the data, it is believed that a cleaner production of low-cost zinc silicate can be achieved by using arecanut husk and have the potential to be used as phosphors materials.

Rare-earth oxides microparticles doped tellurite-based glass have been studied extensively to improve the capability of optoelectronic devices. We report a detailed comparison between two sets of glass series containing samarium microparticles and nanoparticles denoted as ZBTSm-MPs and ZBTSm-NPs, respectively. The two sets of glass have been successfully fabricated via meltquenching technique with chemical formula {[(TeO2)0.70 (B2O3)0.30]0.7 (ZnO)0.3}1-y (Sm2O3 (MPs/NPs))y with y = 0.005, 0.01, 0.02, 0.03, 0.04 and 0.05 mol fraction. The TEM analysis confirmed the existence and formation of nanoparticles in ZBTSm-NPs glasses. The density of ZBTSm-NPs glasses was found higher than ZBTSm-MPs glasses due to the distributions of nano-scale particles in tellurite glass network. There was a linear trend of increment in the refractive index in both sets of glass series along with the concentrations of dopants. The refractive index of ZBTSm-NPs glasses was found higher than ZBTSm-MPs glasses due to the shift in compactness of glass structure with nano-scale particles. In comparison, the absorption peaks of ZBTSm-MPs glasses were greater than ZBTSm-NPs glasses which were mainly due to the restriction of electrons mobility in glass network with nano-scale particles. The optical band gap energy in ZBTSm-NPs glasses was found greater than ZBTSm-MPs glasses which correspond to the widening of forbidden gap with nano-scale particles. The polarizability of ZBTSm-NPs and ZBTSm-MPs was found in nonlinear trends along with dopant concentrations. Based on these findings, the improvement of optical properties has been made by introducing samarium oxide nanoparticles in tellurite glass which is beneficial for optoelectronic devices.