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The aim of this study was to the production of an active film based on Prangos ferulacea root gum, using its leaf's essential oil (PFEO) (0–3 %) and bismuth oxide nanoparticles (Bi 2 O 3 NPs) (0–3 %). Then, the developed film was used for packaging of quail fillet. Response surface methodology was used to evaluate the effect of PFEO and Bi 2 O 3 NPs on films' properties. Optimum formulation, including 1.5 % PFEO and 1 % Bi 2 O 3 NPs, was achieved based on numerical optimization. The optimum film was produced and compared with the control film (based on Prangos ferulacea root gum, without PFEO and Bi 2 O 3 NPs). According to the results, adding PFEO and Bi 2 O 3 NPs to the film formulation increased the thickness and antioxidant activity of the film and decreased moisture content, solubility, water vapor permeability, and whiteness index (p < 0.05). The optimum film indicated high antimicrobial effects on Escherichia coli and Staphylococcus aureus. The pH, TVBN, TBA values, coliform, and total bacterial counts of quail fillet packed with the optimum film were lower and sensorial scores were higher than the control samples during the storage(p < 0.05). [ABSTRACT FROM AUTHOR]

A study is presented on four polymers of the polyurethane family, obtained using a two-stage process. The first composition is the basic polymer; the others differ from it by the presence of a variety of fillers, introduced to provide radiopacity. The fillers used were 15% bismuth oxide (Composition 2), 15% tantalum pentoxide (Composition 3), or 15% zirconium oxide (Composition 4). Using a test culture of human fibroblasts enabled the level of cytotoxicity of the compositions to be determined by MTT (3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide) assay, along with variations in the characteristics of the cells resulting from their culture directly on the specimens. The condition of cells on the surfaces of the specimens was assessed using fluorescence microscopy. It was shown that introducing 15% bismuth, tantalum, or zinc compounds as fillers produced a range of effects on the biological characteristics of the compositions. With the different fillers, the levels of toxicity differed and the cells' proliferative activity or adhesion was affected. However, in general, all the studied compositions may be considered cytocompatible in respect of their biological characteristics and are promising for further development as bases for bone-substituting materials. The results obtained also open up prospects for further investigations of polyurethane compounds. [ABSTRACT FROM AUTHOR]

This research work is basically related to the fabrication of Ca-doped Bi2O3 (Bi2-xCaxO3-δ; where x = 0, 0.10, 0.20, 0.30 and 0.40) based nanoparticles via wet chemical method. Physical characterizations like XRD, FTIR, particle size analysis and SEM were adopted. The prepared Bi2O3 based nanoparticles were indexed to cubic (B.C.) crystalline geometry. FTIR spectra gave useful information about the occurrence of Bi–O bond in the ceramic particles. The occurrence of nanosized grains was authenticated by particle size analysis and SEM. It was found that the prepared nanoparticles were pure and crystalline, hence, they can be used in any technological applications. [ABSTRACT FROM AUTHOR]

Copyright of Hydrometallurgy of China is the property of Hydrometallurgy of China Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Precious Metals / Guijinshu is the property of Precious Metals Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The marble used at construction sites creates a large amount of sludge after processing. Because waste marble has a high calcium oxide content, it is often used as a concrete mix building material. In this study, the use of waste sludge in the fabrication of radiation shields was investigated for medical shielding applications. A shielding sheet was produced by mixing a polymer and waste marble powder. A method for improving the density of the shielding sheet was developed to improve the shielding performance. To improve the density of the shielding sheet using the WMP mixture, the gap between particles was narrowed by making the WMP particles small and by mixing in a material with a proven shielding effect, such as bismuth oxide. In addition, a stirring defoaming process was used to reduce the voids between particles, and we presented a method to control the density by processing the WMP at a high temperature of 1200 °C. The experimental results revealed that the waste marble powder exhibited the highest shielding effect when mixed with radiation shielding materials such as bismuth oxide. The reduction of voids and the size of the particles used in preparing the shielding sheet proved to be effective in reducing the gap between the particles, resulting in an improvement of shielding of approximately 15% to 20%. The investigated shielding material based on waste marble powder was shown to be effective in shielding low-dose radiation. [ABSTRACT FROM AUTHOR]

Gold mine tailings, fly ash, and bagasse ash has been repurposed to produce geopolymer (GP) with enhanced electromagnetic interference shielding efficiency (EMI-SE) and high thermal property. GP has low shielding efficiency compared to concrete. Due to this, an appropriate filler must be incorporated into its matrix to enhance its EMI-SE. For this study, bismuth oxide nanomaterial (BiNP) was utilized as the additive filler. The percent content of BiNP was varied to evaluate its influence on the EMI-SE of GP. Morphology shows that Bi2O3 was embedded in the matrix of GP, and no new aluminu-phyllosilicate minerals were formed. This indicates that some minerals acted only as internal fillers in the matrix. Compressive strength shows synthesized GP composites were more than 20 MPa, with neat GP reaching the maximum strength. Moreover, the EMI-SE of neat GP was 21.2 dB for 20–4500 MHz range. This indicates that GP alone has sufficient characteristics to attenuate EMI radiation. Addition of 5%, 10% and 15% weight of BiNP improves EMI-SE by 4–10%, with 5% BiNP shown to be the optimum ratio. Lastly, the addition of BiNP improves the thermal stability of GP. This study shows that GP incorporated with Bi2O3 can be recommended for small-scale construction and small residential building. [ABSTRACT FROM AUTHOR]

Hydrogen sulfide is one of the harmful gases that contribute to air pollution. Therefore, there is a need to develop high-response hydrogen sulfide (H₂S) gas sensors. Herein, the bismuth oxide nanostructured material was prepared using the hydrothermal chemical route. The prepared material was characterized using XRD, FESEM, TEM, XPS, EDS, and UV–visible spectroscopy techniques. The gas sensor device was fabricated using bismuth oxide nanomaterial, and gas sensing properties were investigated. The sensor exhibited the highest response of 22–92% towards H₂S gas at 250 °C for 10–100 ppm concentration range, respectively. The 92% response was recorded for 100 ppm H 2 S gas with rapid response and recovery times of 511 and 492 s, respectively. The sensor was tested at different operating temperatures and H 2 S gas concentrations. The sensor's selectivity, dynamic resistance response repeatability, and long-term (30 days) stability were studied. The nanostructured bismuth oxide can be a promising candidate for high-response H₂S sensor applications. [Display omitted] • 2D Nanosheets structured BiO x via hydrothermal technique and characterizations. • BiO x sensor exhibiting high response and good selectivity towards H 2 S gas at 250 °C. • BiO x sensor highly sensed in H 2 S gas concentration 10–100 ppm at 250 °C. • BiO x sensor shows dynamic sensor resistance response with excellent repeatability. • BiO x sensor shows long term stability. [ABSTRACT FROM AUTHOR]

Nitrate, a common pollutant in water, can be used as a nitrogen source for electrocatalytic ammonia production. Bismuth oxide (Bi2O3) is a promising electrocatalyst because of earth‐abundance and high hydrogen overpotential. However, it also has the disadvantages of easy agglomeration and poor charge transfer. This study demonstrated that the high dispersion of Bi2O3 nanosheets can be achieved through in‐situ growth on Ti3C2Tx MXene nanosheets that improved the efficiency of charge transmission, and thus improving the electrocatalytic ammonia production performance. A NH3 yield rate of ∼7.00 mg h−1 cm−2 with faradic efficiency of 91.1 % could be achieved on 11 % Bi2O3/MXene. Density functional theory (DFT) calculations, electrochemical active surface area (ECSA) and electrochemical impedance spectroscopy (EIS) proved that the excellent ammonia production performance came from the fact that bismuth oxide itself could inhibit hydrogen evolution, and in situ growth on MXene enabled high active site exposure and enhanced charge transfer capacity. [ABSTRACT FROM AUTHOR]

The fabrication of a nanocomposite comprising polyvinyl alcohol (PVA), polypyrrole (PPy), and bismuth oxide has been prepared using the solution casting method. The fabricated nanocomposite films were analytically characterized, in general, and for gamma irradiation shielding properties, in specific. Various gamma irradiation attenuation parameters were measured using different gamma irradiation energy sources (Co-57, Ba-133, Na-22), with the help of the Geiger Muller detector and NIST-WinXCOM database. On increasing the contents of Bi2O3 NPs in the PVA-PPy matrix, the composite's mass attenuation coefficients were enhanced significantly, and the effectiveness of gamma irradiation shielding improved overall and particularly at gamma rays energy of 122 keV. The increasing trend of mass attenuation coefficients was observed for low gamma-ray energy sources up to 30 wt% nanofiller contents, whereas it reduced for high dose gamma energy sources like Na-22, as compared to Co-57 and Ba-133. The half-value layer (HVL) and tenth value layer (TVL) showed a decreasing trend for the low gamma-ray energy source. With a 1274 keV gamma energy source, the values of HVL and TVL steadily increased until the nanofiller incorporation reached up to 30 wt%. The values of investigated coefficients using the NIST-WinXCOM database have been found in good agreement with the experimental results. The lead-free PVA-PPy-Bi2O3 nanocomposites have shown promising shielding properties for low energy gamma irradiation and might be a good alternative for conventional radiation shielding material in nuclear medicine diagnostics and treatment centers. [ABSTRACT FROM AUTHOR]

The purpose of this research is to evaluate the intent of empty fruit bunches of palm oil (EFBpalm oil) to catalytic gasification of wood produced charcoal (Woodcharcoal) in order to notify the large-scale application of Woodcharcoal as a possible gasification feedstock. In this study, co-catalyst of bismuth oxide (Bi2O3) was also used to obtain syngas. The raw samples were characterized by proximate and ultimate analyses, X-ray diffraction (XRD), field emission scanning electron microscope (FESEM), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS) analyses. The produced syngas was analyzed by online portable gas analyzer and gas chromatography-thermal conductivity detector (GC-TCD). The syngas composition of H2 increased from 3.91 to 4.70% (increased 20.20%), CO increased from 5.73 to 6.30% (increased 10.53%), whereas CO2 decreased from 20.60 to 12.67% (decreased 38.50%) and CH4 concentration increased insignificantly from 0.35 to 0.37% (increased 5.7%) which was happened due to the use of WoodCharcoal and Bi2O3 with EFBpalm oil during gasification. According to the findings, carbon is abundant in WoodCharcoal, which may considerably boost the gasification reactivity with Bi2O3. The yield of syngas (H2 and CO) increased when WoodCharcoal and Bi2O3 were used instead of single EFBppo gasification, indicating that catalyst (WoodCharcoal) and co-catalyst (Bi2O3) have a high potential for thermal decomposition and dehydrogenation of volatile matter. Therefore, catalytic gasification of empty palm fruit bunches will be the prospective energy sources for the production of syngas with the utilization of WoodCharcoal and Bi2O3. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the effect of three concentrations of bismuth trioxide (Bi2O3) on the biological and physicochemical properties of an experimental mineral trioxide aggregate-type (MTA-type) cement at different time points. Methods: Three experimental groups with white Portland cement containing 15, 20, or 25 wt% of Bi2O3 were assessed. Cellular proliferation in human periodontal ligament fibroblasts was evaluated with an MTT assay. Radiopacity, dimensional stability, pH, and compressive strength were evaluated at different time points. Results: Bismuth trioxide induced cell proliferation in the Bi15 and Bi25 groups in a time-dependent manner; pH was similar in all groups. Compressive strength was associated with time and bismuth concentration. Bi25 had significantly contracted at day 7 and expanded at day 14 (ANOVA P < 0.05, post hoc Tukey test P < 0.05). Conclusion: A higher Bi2O3 concentration had a negative effect on the physical properties of the cement at all time points. [ABSTRACT FROM AUTHOR]

Due to the high prevalence and considerable increase of prostate cancer, finding novel therapeutic compounds for the treatment of prostatic cancer has been the goal of many researches. In this study, we aimed to fabricate the Bismuth oxide (Bi2O3) NPs, functionalized with glutamine (Gln) and conjugated with Thiosemicarbazide (TSC). Then, the anticancer mechanism of the synthesized NPs was investigated using the cellular and molecular tests including MTT assay, Flow cytometry, Caspase-3 activity assay, Hoechst staining and Real Time PCR. The FT-IR and XRD assays confirmed the identity of the synthesized Bi2O3/Gln-TSC NPs. The size range of the synthesized spherical particles was 10–60 nm and the zeta potential was − 23.8 mV. The purity of the NPs was confirmed by EDX-mapping analysis. The Bi2O3/Gln-TSC was considerably more toxic for prostate cancer cells than normal human cells and the IC50 was calculated 35.4 and 305 µg/mL, respectively. The exposure to the NPs significantly increased the frequency of apoptotic cells from 4.7 to 75.3%. Moreover, the expression of the CASP8, BAX, and Bcl-2 genes after exposure to the NPs increased by 2.8, 2.3, and 1.39 folds. Treating the cancer cells with Bi2O3/Gln-TSC increased the activity of the Caspase-3 protein and apoptotic morphological features were observed by Hoechst staining in the treated cells. This work showed that Bi2O3/Gln-TSC has considerable cytotoxicity for prostate cancer cells and could inducing both intrinsic and extrinsic pathways of apoptosis. [ABSTRACT FROM AUTHOR]

Developing and utilizing solar to chemical energy conversion is a promising and efficient approach to green carbon-neutral energy systems. Herein, we report a facile solvothermal reaction strategy using black phosphorus (BP) nanosheets coupled with bismuth oxychloride (BiOCl) to prepare uniform BP/BiOCl composite nanocatalysts with enhanced wide-spectrum light absorption and electron-rich P modulated surface acid–base properties. BP/BiOCl possesses a typical layered structure showing the features of excellent separation of electron–hole pairs and electron transfer for efficient photocatalytic CO2 reduction to CO. Notably, the engineered BP/BiOCl nanocomposite with substantial BP–BiOCl synergy exhibits a superior CO production rate of up to 260 μmol g−1 h−1, which is 130 and 13 times higher than those of BP and BiOCl counterparts, respectively. Meanwhile, the BP/BiOCl material shows excellent photostability for CO2 transformation under visible light irradiation. The 13C isotope labeling experiment confirms that the carbon source of C-containing products is derived from the CO2 substrate during the photocatalysis process. The S-scheme mechanism involving excited electron transfer and direct participation in chemical activation of inert CO2 molecules, generation of key intermediate CO*, and final gas products for photocatalytic CO2 reduction over the BP/BiOCl composite is thus proposed. [ABSTRACT FROM AUTHOR]

Lead‐based shielding materials are commonly used to protect clinical personnel and patients from high energy x‐ray radiations. However, the toxicity and heavy weight of lead can result in serious health concerns and limit its applications. Alternatively, polymer composites are known as one of the potential candidates to shield high energy photons. Herein, polydimethylsiloxane (PDMS) nanocomposites are fabricated using different weight percentages (wt.%) of bismuth oxide (Bi2O3) and multi walled carbon nanotube (MWCNT) nanoparticles. The mechanical strength of nanocomposites is evaluated by Instron 5548 Micro Tester. Also, x‐ray shielding properties are characterized using continuous x‐ray energies from 60 to 90 keV. To study the effect of the nanocomposite structure on mechanical and shielding properties, multilayer nanocomposites in 2 to 5 layers are also fabricated with alternately PDMS/Bi2O3 and PDMS/MWCNT layers and are characterized by the same methods. The 5‐layer nanocomposite improves the mechanical strength from 1.7 MPa in neat PDMS to 4.68 MPa. It is also capable of attenuating 89% of the scattered x‐rays generated at a tube potential of 60 keV, with a weight advantageous in comparison with pure lead. [ABSTRACT FROM AUTHOR]

Low content of oxygen vacancy defects (OVs) and limited resistibility to photocorrosion are the core problems in the heterogeneous photocatalytic processes of bismuth oxide (Bi2O3). Herein, the strategy of "ultraviolet (UV) light‐inducing OVs" coupling with "polyaniline (PANI) combination inhibiting photocorrosion" is employed on the modification of Bi2O3. First, the high methylene blue (MB) degradation efficiency by UV3h‐Bi2O3@PANI0.5 wt% above 99.5% and the low Bi3+ dissolved concentration below 0.20 mg L−1 under visible light signify the high photocatalytic activity and stability. Then, the mechanisms for generation of OVs and inhibition of photocorrosion are proposed as follows. 1) Holes (h+) forming under irradiation, diffusing through the lattice, and reaching the surface of Bi2O3 can be regarded as a monatomic oxygen ion (OS−); 2) OS− combines and continues to be oxidized by h+, leading to the generation of O2 with the OVs left in the lattice; 3) UV‐Bi2O3 and PANI are excited to produce electrons/holes (e−/h+); 4) e−/h+ transfer in UV‐Bi2O3@PANI heterojunction leads to the separation of h+ from UV‐Bi2O3 and the inhibition of photocorrosion. Through the core problems being overcome, a new idea for the development and application of Bi2O3 with excellent performances in the field of water treatment is provided. [ABSTRACT FROM AUTHOR]

The structures of glasses in the lithium–bismuth orthoborate composition range deviate significantly from the short‐range order structure of the two crystalline end‐members. Although binary Li3BO3 and BiBO3 are solely of comprised trigonal orthoborate anions, all glasses formed by their combination contain four‐coordinated borate tetrahedra. We analyze the structure of (75−1.5x)Li2O–xBi2O3–(25+0.5x)B2O3 glasses in increments of x = 5, with 11B magic‐angle spinning nuclear magnetic resonance (NMR), infrared (IR), and Raman spectroscopy. For the full series, the oxygen‐to‐boron ratio remains constant at O/B = 3:1. NMR quantifies an increase in the fraction of tetrahedral boron with increasing bismuth oxide content. Evolution of the mid‐IR profile suggests multiple types of tetrahedral boron sites. Raman spectroscopy reveals that Bi2O3 tends to cluster within the lithium borate matrix when initially introduced and that this behavior transforms into a bismuthate network with increasing bismuth oxide content. In all cases, mixed Bi–O–B linkages are observed. The dual role of bismuth as network modifier and network former is likewise observed in the far IR. The glass transition temperature continuously increases with bismuth oxide content; however, the glass stability displays a maximum in the multicomponent glass of x = 40. [ABSTRACT FROM AUTHOR]

Constructing visible-light-active Z-scheme heterojunctions has proven fruitful in enhancing the photocatalytic activity of photocatalysts for superior water clean-up. Herein, we report the fabrication of a CoFe2O4@Bi2O3/NiO (CBN) Z-scheme nanoheterojunction. The obtained CBN heterojunction was used for visible-light-assisted degradation of ofloxacin (OFL) in water. The OFL degradation efficiency achieved by the CBN heterojunction was 95.2% in 90 min with a rate constant of kapp = 0.03316 min−1, which was about eight times that of NiO and thirty times that of CoFe2O4. The photocatalytic activity of a Bi2O3/NiO Z-scheme heterojunction was greatly enhanced by the visible activity and redox mediator effect of the cobalt ferrite co-catalyst. Higher charge-carrier separation, more visible-light capture, and the Z-scheme mechanism in the Z-scheme system were the important reasons for the high performance of CBN. The scavenging experiments suggested ●O2− as an active species for superior OFL degradation. The possible OFL degradation pathway was predicted based on LC-MS findings of degradation intermediate products. The magnetic nature of the CBN helped in the recovery of the catalyst after reuse for six cycles. This work provides new insights into designing oxide-based heterojunctions with high visible-light activity, magnetic character, and high redox capabilities for potential practical applications in environmental treatment. [ABSTRACT FROM AUTHOR]

Bismuth oxide kinetically stabilized by doping with a metastable structure of disordered fluorite δ-Bi2O3 has a unique conductivity. Oxygen selective membranes at intermediate temperatures ~550 °C, on the base of cermet δ-Bi2O3/Ag, have the highest potential for air separation and can be used to produce oxygen for distributed multigeneration by burning fossil carbon fuels. When searching for the optimal composition of δ-Bi2O3, the degradation of fluorite into a new tetragonal phase was discovered in ceramics synthesized using mechanical activation. The tetragonal phase is formed and exists in a topotaxial composite with the fluorite structure. For a relatively stable over a wide temperature range tetragonal phase with a = 0.3854, c = 0.88905 nm, S.G. P-4, crystal structure and atomic coordinates have been proposed. In samples of fluorite and topotaxial composite, the Raman and Mössbauer spectra were recorded and discussed. The discovery of a new tetragonal phase of doped bismuth oxide and its existence area makes it possible to optimize the composition and the synthesis of a more stable solid electrolyte δ-Bi2O3 with high conductivity. [ABSTRACT FROM AUTHOR]

Bismuth containing porous glasses (BPGs) were prepared on the basis of high-silica micro- and macroporous glasses and also of microporous glasses thermally treated at 750°C. The chemical composition of the glasses was determined by standard analytical methods and X-ray fluorescence analysis. Energy dispersive X-ray analysis showed that bismuth is predominantly formed at the half-thickness of the membranes. Characterization of the glass morphology was carried out by scanning electron microscopy. Their structural properties (specific surface area, volume porosity, structural resistance coefficient, average pore radius) and electrosurface ones (specific electrical conductivity, transport numbers of ions in the pore channels, electrokinetic potential) were studied in 10−4–10−1 M KNO3 solutions in a neutral pH range. The results were compared with similar properties of PG membranes not modified with bismuth(III) oxide. Porous glasses doped with bismuth oxide were found to restore their electrosurface characteristics in the neutral pH range in the concentration range of KNO3 solutions under study. [ABSTRACT FROM AUTHOR]

Composite materials (CMs) based on matrices of high-silica nanoporous glasses (NPGs) activated by bismuth and yttrium ions are synthesized. The CMs are studied by IR spectroscopy (1000–400 cm–1), depending on the Bi/Y nitrate ratio in the solution (1 : 1 and 10 : 1) and the heat treatment temperature of the CMs (from 470 to 870°C). The method of IR spectroscopy in composites identifies vibrations characteristic of the cubic modification Y2O3 and for the monoclinic modification of bismuth oxide (α–Bi2O3); for vibrations of Bi–O and Bi–O–Bi bonds, as well as Bi3+ cations in [BiO6] and/or [Bio3] structural units; and for vibrations of Bi–O–Si bonds, and for Y–O–Y and Y–O bonds. It is established that an increase in the yttrium content in CMs heat-treated at 470 and 870°C, (all other things being equal) leads to the appearance of additional absorption bands at 564, 556, 432, and 424 cm–1, which may be related to the formation of the cubic phase Y2O3. [ABSTRACT FROM AUTHOR]

Copyright of Hydrometallurgy of China is the property of Hydrometallurgy of China Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The bimetal oxide comprising nickel incorporated β-Bi 2 O 3 on graphitic carbon in the form of bismuth nickel oxide (BNO@C) was prepared by waste lignocellulosic materials collected from cheap and readily available baby diapers. The prepared BNO@C was used to photocatalytically degrade methylene blue under UV-light irradiation. Prior to the photocatalytic performance analysis, the formation of BNO@C was confirmed by various morphological and structural analysis including SEM, TEM, XRD, and XPS analyses. As a result, the two-dimensional nanosheet morphology and tetragonal primitive lattice-structure with 2+ and 3+ oxidation stated Ni and Bi in BNO@C structural formulation were confirmed. In photocatalysis experimentation examined with BNO@C, the maximum methylene blue removal percentage of 96.7 % was achieved within 16 min. The influence of Ni2+ in BNO@C was identified by performing the photocatalytic performance of bare NiO@C and Bi 2 O 3 @C, yielding maximum dye removal of 32.8 % and 64.5 %, respectively. The efficacy of Ni in BNO@C toward increasing catalytic efficiency was identified using DFT analysis, revealing the acting of Ni as active sites for improved light absorption tendency. These findings show a novel strategy to prepare a low-cost BNO@C catalyst with efficient photocatalytic activity, opening a new path for a cost-efficient wastewater treatment approach. [Display omitted] [ABSTRACT FROM AUTHOR]

Bismuth oxide (Bi 2 O 3) has been extensively investigated in the fields of environmental photocatalysis, owing to its exceptional charge transport performance and remarkable resistance to photocorrosion. However, the limited absorption spectrum of light and rapid recombination of photogenerated charge results in a low quantum efficiency. Herein, an efficient photocatalytic system for tetracycline hydrochloride (TCH) photodegradation based on titanium (Ti)-doped hollow, thin-walled Bi 2 O 3 with nano-microspheres is fabricated via a facile self-assembly strategy. It is shown that doping Ti in Bi 2 O 3 can generate oxygen vacancies, in addition, the addition of Ti in the solvothermal process inhibits the conversion of Bi3+ to bismuth at high temperature, making the content of each component in the heterostructure controllable. The hybrid catalyst exhibits superior performance in visible-light-driven photocatalytic degradation of TCH (about 95.1 % degradation efficiency after 120 min) and excellent stability (up to 4 cycles) under visible light irradiation. The optimized catalyst exhibits excellent performance in visible light catalytic degradation, owing to the synergistic effect of high specific surface area, Bi plasma resonance effect and charge mobility. Moreover, the photocatalytic mechanism of Ti-Bi 2 O 3 have been deeply analyzed through experimental investigation and DFT theoretical calculations. The findings contribute to the synthesis of efficient visible-light-driven Bi-based photocatalysts and to the understanding of photocatalytic degradation reactions. [Display omitted] ● Ti-doped Bi 2 O 3 with hollow microspheres synthesized by hydrothermal method. ● The synergistic effects of Ti enhanced structural and physicochemical properties. ● Hollow thin-walled structure displays an importance role in photocatalysis. ● Ti-Bi 2 O 3 -450℃ exhibited high performance of removal organic pollutant. ● The photocatalysis system increases active sites and inhibits e--h+ recombination. [ABSTRACT FROM AUTHOR]

• Green synthesis yields efficient bismuth ferrite@molybdenum trioxide heterostructures. • Remarkable dye degradation rates for RhB (98 %), methyl blue (96 %), and methyl orange (95 %) were achieved. • Enhanced stability and recyclability were maintained over five consecutive cycles. • Heterostructure reduced recombination rate contribute to superior photocatalytic performance. • Promising catalyst for sustainable water treatment and environmental remediation applications. Photocatalysis has become increasingly pervasive in the chemical industry, profoundly impacting operational costs. However, an ideal photocatalyst must possess characteristics such as excellent reactivity, high selectivity, prolonged stability, low toxicity, and cost-effectiveness. Moreover, it should facilitate the efficient separation of photo-generated charge carriers, thereby minimizing recombination rates. In pursuit of advancing photocatalytic activity for sustainable water treatment, this investigation focused on synthesizing a groundbreaking photocatalyst, the Bismuth Ferrite@Molybdenum trioxide heterostructure, using an eco-friendly green chemistry technique with pomegranate extract. This approach aligns with the goal of environmental sustainability and represents a novel contribution to the field. Employing a comprehensive approach, advanced characterization techniques such as XRD, SEM, FT-IR, and UV–Vis were applied to analyze the material's structural, morphological, and optical properties. According to the characterization results, the heterostructure demonstrates superior photocatalytic efficiency, heightened crystallinity, and reduced recombination rates during dye degradation for water treatment compared to both individual photocatalysts. Notably, the composite catalyst exhibits a synergistic impact, outperforming individual BiFeO 3 and MoO 3 photocatalysts. SEM observations confirm the successful integration of rod-like MoO 3 and cylindrical BiFeO 3 morphologies, highlighting the strategic combination achieved through the green chemistry route. Furthermore, UV–Vis spectroscopy reveals key optical parameters, emphasizing a narrow bandgap energy of 2.74 eV with a high refractive index of 2.43 eV. The exceptional efficacy of the heterostructure in degrading dyes within the visible spectrum, surpassing expectations within a 4-hour timeframe, highlights its efficiency and precision. Remarkably, achieved degradation rates for Rhodamine B dye (98 %), Methyl Blue (96 %), and Methyl Orange dye (95 %) highlights the promising role of proposed photocatalytic system in effectively addressing water pollutant challenges. [Display omitted] [ABSTRACT FROM AUTHOR]

The present work focuses on the investigation of the properties of 33TeO 2 : 30B 2 O 3 : 30ZnO: 5BaO: 2Eu 2 O 3 glass prepared using microwave and conventional techniques. The prepared glasses were characterized by TGA/DSC analysis, density, refractive index, FTIR, XPS, absorption spectra, photoluminescence, lifetime, quantum efficiency, and X-ray-induced luminescence properties. The photoluminescence of the samples exhibited the strongest luminescence intensity of the Eu3+ ion at 614 nm (7F 2) under 394 nm excitation, resulting in a relatively high photoluminescence quantum yield of 39.64%. The luminescence decay time from the 5D 0 to 7F 2 level of glass prepared by the microwave technique is lower than that of a sample prepared by the conventional technique, with a luminescence decay time of 1.269 and 1.425 ms, respectively. X-ray-excited luminescence spectroscopy identified an emission peak at 614 nm in the samples, which can be attributed to 5D 0 -7F 2 transitions in the Eu3+ ion. These high-intensity samples were compared with bismuth germanate oxide (BGO) crystals used in radiation detection applications. From the various results examined, it is clear that the 33TeO 2 : 30B 2 O 3 : 30ZnO: 5BaO: 2Eu 2 O 3 glass prepared using the microwave technique is suitable for use as a scintillation material. • Microwave melting (MIC) yields glass with a higher proportion of NBO compared to conventional melting (MELT). • MIC glass exhibits the photoluminescence intensity higher than MELT glass 7 times. • The luminescence decay time of MELT glass is 1.425 ms and MIC glass is 1.269 ms. • The integral scintillation efficiency of MIC glass is 11.02% relative to the BGO crystal. [ABSTRACT FROM AUTHOR]

In recent years, scientists have been confronted with the formidable task of wastewater management due to the occurrence of intricate organic pollutants. In this study, we constructed the zirconium-substituted copper bismuth oxide (Zr0.2Cu0.8Bi2O4) through an easy hydrothermal method and effectively employed it to eliminate complex organic pollutants. The evaluation of the photocatalytic efficiency of the catalysts was conducted toward the degradation of rhodamine B (RhB) under visible light irradiation. According to the experimental results, the RhB dye had a degradation rate of 79.16% when a CuBi2O4 catalyst was utilized. In contrast, the degradation rate of the Zr0.2Cu0.8Bi2O4 catalyst escalated to 98.34% in 35 min. Comparably, the rate constant of 0.1041 min−1 was observed for Zr0.2Cu0.8Bi2O4, approximately 2.35 times higher than that of pure CuBi2O4 (0.0443 min−1), thereby confirming the photocatalytic efficacy of the Zr0.2Cu0.8Bi2O4 catalyst. The enhanced photocatalytic effectiveness of the Zr0.2Cu0.8Bi2O4 catalyst can be attributed to its augmented surface area (83.57 m2/g) compared to CuBi2O4 (76.67 m2/g) and lowered bandgap energy of Zr0.2Cu0.8Bi2O4 (1.62 eV) than CuBi2O4 (1.76 eV) resulting from the integration of Zr4+ ions into the fundamental structure of CuBi2O4. Furthermore, analyzing the effects of various reaction variables showed a strong correlation with the removal of RhB dye. One plausible explanation for the degradation of RhB is the production of O2•− and •OH radicals on the catalyst surface. The synthesized Zr0.2Cu0.8Bi2O4 catalyst has shown exceptional photostability after five consecutive cycles. This study introduces a pragmatic and cost-effective method for producing catalysts that are efficient in the treatment of wastewater. [ABSTRACT FROM AUTHOR]

Herein, a novel rod-like bismuth bromide oxide (rBOB) was prepared by using a Bi3+ delayed-release strategy and H+ capping competition effect. And rBOB was combined with graphite carbon nitride (CN) to construct S-scheme heterojunction material (CN/rBOB). This work focused on the regulation mechanism of the rod-like morphology of rBOB and the photocatalytic H 2 O 2 production (PHP) performance of CN/rBOB under the action of an external magnetic field. The results showed that the magnetic field can significantly increase the photocurrent response and intrinsic carrier concentration of the catalyst. And the magnetic field action improved the PHP of CN/rBOB from 1.81 to 3.31 mmol·g−1·h−1. This "internal electric field-external magnetic field" synergistic tuning obviously improves the efficiency of photogenerated carrier separation and transport to the surface active sites, which is a simple and useful strategy to construct high-quality photocatalytic systems. • S-scheme heterojunction of the CN/rBOB were synthesized with superior photocatalytic H 2 O 2 production activities. • Precise modulation rod-like morphology of rBOB by Bi3+ delayed-release strategy and H+ capping competition effect. • MF assisted inhibition of photogenerated carriers recombination leads to increased intrinsic carriers concentration. • IEF amplifies the MF gain effect, further increasing the photocatalytic activity of the CN/rBOB by factors of 1.8. [ABSTRACT FROM AUTHOR]

[Display omitted] • Design and synthesis of monodispersed spherical Bi 2 O 3 NPs. • Enhanced vitamin B 12 detection using Bi 2 O 3 NPs/GCE system. • Attainment of a wide linear range with excellent LOD. • Selective sensing of vitamin B 12 in the presence of various interference molecules. The intake and monitoring of vitamin B 12 levels are highly essential to maintain a healthy body condition. Herein, we report bismuth oxide nanoparticles (Bi 2 O 3 NPs) facilitated electrochemical sensing of vitamin B 12 with admirable sensitivity, selectivity, and low detection limit. A facile hydrothermal method was adopted for synthesizing Bi 2 O 3 NPs and their physico-chemical properties were analyzed using various techniques. The electrochemical sensing of vitamin B 12 was validated through cyclic voltammetry and differential pulse voltammetry techniques. The sensing results illustrate that the modified electrode exhibits a wide linear range between 10 nM and 275 nM with a low detection limit value of 3.66 nM. In addition to the enhanced electrocatalytic behavior, the Bi 2 O 3 NPs have also enabled the discrimination of vitamin B 12 from various potential interfering molecules (even adding a 5-fold concentration). The developed sensor also exhibits better stability, selectivity, and reproducibility towards the target analyte. Finally, the fabricated electrode was applied for the determination of vitamin B 12 in serum, and plasma samples, and the results were highly satisfactory with recovery values of 98.4 % to 99.8 %. [ABSTRACT FROM AUTHOR]

Holes accumulation on the surface of bismuth ferrite oxides (BFO) photoanodes for photoelectrochemical (PEC) water splitting (WS) is one of the major issues limiting the overall cell efficiency. However, among the various BFO crystal structures, no evidence of this mechanism has been reported for Bi 24 Fe 2 O 39 , a scarcely investigated phase. Herein we characterize the morphological, structural and PEC properties of 100 nm thick nanogranular films of a Bi 24 Fe 2 O 39 single phase synthesized by supersonic cluster beam deposition. The films were tested as photoanodes for the WS reaction in KOH and Na 2 SO 4 + Na 2 SO 3 electrolytes. The PEC data provide direct evidence of holes accumulation on the surface of the material with increasing applied biases. The interesting performances of this material at low biases suggest a possible use as photocatalyst under visible light irradiation. [Display omitted] • Growth of Bi 24 Fe 2 O 39 photoanodes by supersonic cluster beam deposition of nanoparticles • Chemico-physical, morphological and photoelectrochemical characterization • Determination of reaction kinetic constants • Holes accumulation on the surface states to explain the photoelectrochemical performance [ABSTRACT FROM AUTHOR]

The formation of bismuth and copper nanoparticles from CuO–Bi 2 O 3 –SiO 2 glass by heat treatment in the presence of hydrogen and their functionality as anode active material in sodium ion batteries was examined. Oxides consisting of xCuO-(85-x)Bi 2 O 3 –15SiO 2 (mol%) vitrify in the composition range of x from 5 to 30. In compositions with large amounts of copper oxide (x > 35), Cu 2 O crystallizes, suggesting the presence of Cu+ and Cu2+ with different valence states in the glass. Heat treatment in a mixed atmosphere of hydrogen and nitrogen resulted in the crystallization of bismuth oxide and their reduction to form glass ceramics with dispersed bismuth and copper particles. As bismuth and copper are consumed from the glass matrix by phase separation, a cross-linked structure of silica develops in residual glass matrix. The resulting bismuth particles was small in size than borate-based glass ceramics, indicating that the cross-linked silicates have an inhibiting effect on bismuth grain growth. Charge-discharge tests in a sodium ion battery showed a reversible charge-discharge profile without the initial irreversible reaction of bismuthate reduction. Backscattered electron microscope image and elemental mapping images of 20CuO-65Bi 2 O 3 -15SiO 2 heat treated at 400°C for 3 h. [Display omitted] • Heat treatment of CuO–Bi 2 O 3 –SiO 2 glass in hydrogen induces phase separation of bismuth particles. • The addition of CuO to the glass composition improves the glass-forming ability. • The irreversible reaction due to the reduction of bismuth oxide was suppressed. [ABSTRACT FROM AUTHOR]

This paper investigates the pivotal role of bismuth oxide (Bi₂O₃) in the enhancement of nuclear safety, structural, and thermal properties of glasses, specifically in the BNLS system. BNLS system has the formula [B 2 O 3 –Li 2 O–SiO 2 ]-Nb 2 O 5(20-x) –(Bi 2 O 3) x (where x = 0.0,5.0,10.0,15.0 and 20.0 mol%). Through a comparative study, the potential advantages, and limitations of integrating Bi₂O₃ in place of traditional elements are highlighted, emphasizing its importance in the field of advanced glass materials. FTIR analysis showed the presence of Bi–O vibrations of the tetrahedral [BO 4 ] groups and the Bi–O–Bi linkages. DSC testified the glass formation with increasing thermal stability of the formed glass with the inclusion of Bi 2 O 3 into the glass system. Through the quantification of the Gamma Linear Attenuation Coefficient (G LAC) and Gamma Mass Attenuation Coefficient (G MAC), the work identifies the attenuation behavior against varying photon energies. Notably, a concentration-dependent rise in attenuation characteristics is observed, with BNLS20 exhibiting the most potent radiation shielding. Glass Half-Value Layer (G HVL) parameters and Mass Gamma Photon Penetration (G MFP) were measured, reinforcing that glasses with higher Bi 2 O 3 concentrations and lower G HVL are better attenuators. The transmission factor (ln(I/Io)) was also studied, confirming that BNLS20 possesses the most effective radiation shielding capabilities. This research establishes that adding Bi₂O₃ to the [B 2 O 3 –Li 2 O–SiO 2 ]-Nb 2 O 5 glass system markedly improves its thermal stability and radiation shielding capabilities. BNLS20, in particular, emerges as a standout for radiation protection, surpassing both other BNLS variants and conventional shielding materials, thereby positioning it as an exceptional choice for advanced nuclear safety applications. • The substitution of Bi₂O₃ for Nb₂O₅ in a [B₂O₃-Li₂O–SiO₂]-Nb₂O₅ glass system was studied. • The structural, thermal, and nuclear safety for the glass system were investigated. • Gamma shielding characteristics of the materials were investigated. • Remarkable results in thermal and nuclear safety properties were obtained. [ABSTRACT FROM AUTHOR]

[Display omitted] • XRD depicts formation of small grains compatible with optoelectronic application. • RhB-functionalized turn-off sensor detect CLP molecule, even at low concentration. • Synthesized hybrid composite shows potential to monitor pesticides. Rhodamine B(RhB) functionalized Bismuth Ferrite Oxide(BFO)/Titanium dioxide(TiO 2)/Silver disulfide(AgS)nanoparticles were used to build a fluorescent turn-off sensor for the detection of Chlorpyrifos(CLP). The fluorescence was drastically quenched by the RhB fluorescence resonance energy transfer to the surface of BFO/TiO 2 /AgS NCs via electrostatic interactions. Then the addition of CLP to RhB@BFO/TiO 2 /AgSNCs initiates the loss of fluorescence by the adsorption of CLP molecules to the turn-off sensor probe. Under favorable conditions, the linearity between the fluorescence quenching and the concentrations was monitored and the limit of detection was estimated to be 0.006 ppm, 0.004 ppm for 2:1 and 3:1 ratio, with the fluorescence quenching efficiency ranges from 92.9 to 94 %. [ABSTRACT FROM AUTHOR]

[Display omitted] • Recovery of Sb and Bi from wastes generated in Cu pyrometallurgical industry. • Need to control redox state to avoid precipitation of insoluble arsenates. • Validation of chemical speciation database for Sb and Bi in acidic media. • Conversion of antimony and bismuth oxychlorides into oxides. • Recovery of Sb 2 O 3 and Bi 2 O 3 with purities higher than 97% The copper pyrometallurgical industry faces challenges in maintaining copper purity due to increasing impurities in primary resources. Notably, Sb, Bi, and As can form insoluble compounds, compromising copper purity in electrorefining units. To address this, ion-exchange (IX) technology is employed to continually treat copper electrolyte of the electrorefining stage, removing Sb and Bi and ensuring a high copper purity (99.99 %). Upon IX resin saturation, regeneration with 6 M HCl produces a concentrated eluate containing Sb, Bi (7–14 g/L each), and As (1–4 g/L). Currently, lime treatment removes these impurities without valorization, which produces large volumes of waste containing As, Sb and Bi. Recognizing Sb and Bi as critical raw materials, this study aims to develop a valorization route, with the objective of recovering both elements free of As using selective precipitation. Pre-treating the eluate to reduce As and Sb to the (+III) state prevented mixed mineral phases, enabling the recovery of high purity Sb 4 O 5 Cl 2 (s) and BiOCl(s) containing low contents of impurities as As. Further improvement could be achieved with the conversion of the oxychlorides to the oxide forms (M 2 O 3 (s)) in alkaline media for potential commercial use. This research contributes to sustainable metal recovery and addresses toxicity concerns associated with As, paving the way for enhanced environmental and economic outcomes in the copper industry. [ABSTRACT FROM AUTHOR]

[Display omitted] • Synthesis of bismuth oxide NPs (Bi 2 O 3 NPs) by solution combustion process. • Bi 2 O 3 NPs exhibited crystallite sizes of 53.34 nm and 44.83 nm, synthesized with urea and lemon juice fuels. • Bi 2 O 3 NPs showed good photocatalytic behavior for Rose Bengal (RB), Acid Orang-88 (AO-88) and Crystal Violet (CV) dyes. • Modified Bi 2 O 3 NPs electrode revealed superior electrochemical sensing for ascorbic acid. The solution combustion approach to synthesize bismuth oxide (Bi 2 O 3) nanoparticles using urea and lemon fuels is demonstrated in this work. The product exhibits a monoclinic phase confirmed by the powdered X-ray diffraction pattern analysis. The Scherrer's approach reveals that the crystallite size was within the range of 40–60 nm and matches transmission electron microscopy (TEM) data. The high energy electron microscopy techniques such as TEM and scanning electron microscopy (SEM) along with energy dispersive X-ray (EDAX), are used for the surface morphology and elemental analysis. The bandgap energy (E g) values were determined using Diffuse Reflection Spectroscopy (DRS). The synthesized nanoparticles exhibit greater photodegradation efficiency when exposed to Acid Orange-88 (AO-88), Crystal violet (CV) and Rose Bengal (RB) dyes under UV light. The electrochemical sensor studies involve the detection and quantification of ascorbic acid in an acidic medium with the help of cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) by modification of carbon paste electrode. These findings indicate that the synthesized sample has potential applications in photocatalytic and electrochemical sensor fields. [ABSTRACT FROM AUTHOR]

Erratum: "Cold sintering of yttria-stabilized cubic bismuth oxide: Conductivity and microstructural evolution of metastable grain boundaries with annealing" [J. Appl. Phys. SEM microstructure (a), temperature dependence of the total conductivity (b), complex impedance plot at 300 °C (c), and 400 °C (d) of BYO ceramics prepared by solid-state sintering at 650 °C without CSP. This correction has no impact on the results, discussion, or conclusions presented in the original article.[1] We apologize for any inconveniences this mistake may have caused. [Extracted from the article]

Mineral trioxide aggregates (MTA) have been widely used in endodontic treatments, but after some time, patients suffer tooth discoloration due to the use of bismuth oxide (Bi2O3) as a radiopacifier. Replacement of Bi2O3 with high energy ball-milled single (zirconia ZrO2; hafnia, HfO2; or tantalum pentoxide, Ta2O5) or binary oxide powder was attempted, and corresponding discoloration improvement was investigated in the present study. Bi2O3-free MTA is expected to exhibit superior discoloration. The radiopacity, diametral tensile strength, and discoloration of MTA-like cements prepared from the as-milled powder were investigated. Experimental results showed that MTA-like cements prepared using Ta2O5 exhibited a slightly higher radiopacity than that of HfO2 but had a much higher radiopacity than ZrO2. Milling treatment (30 min to 3 h) did not affect the radiopacities significantly. These MTA-like cements exhibited superior color stability (all measured ΔE00 < 1.0) without any perceptible differences after UV irradiation. MTA-like cements prepared using ZrO2 exhibited the best color stability but the lowest radiopacity, which can be improved by introducing binary oxide. Among the investigated samples, MTA-like cement using (ZrO2)50(Ta2O5)50 exhibited excellent color stability and the best overall performance with a radiopacity of 3.25 mmAl and a diametral tensile strength of 4.39 MPa. [ABSTRACT FROM AUTHOR]

This research aims to investigate a ternary nanocomposite based on High Density Polyethylene/ Bismuth Oxide/Graphene Oxide (HDPE/Bi2O3/GO) at various concentrations. Solution method was used to fabricate the samples. FESEM-EDX mapping, AFM, TEM, XRD, XPS, FTIR, and TGA/DTG analyses were carried out on the samples. XRD analysis demonstrated a semi-crystalline behavior for the samples. TEM analysis exhibited a cauliflower-like structure of the material. The sample was irradiated by gamma-rays of 60Co source over the dose rate of 30–254 mGy/min and the electric current was measured as the response of the real-time dosimeter. Thus, various dosimetric characteristics were performed, namely linearity, angular dependence, energy dependence, bias-polarity, field size, and repeatability of the data. Results showed that response of the dosimeter was linear in the range of the investigated dose rate. The sensitivity of the 60 wt% Bi2O3 sample was measured as 3.4 nC·mGy−1. The angular response variation was 20% for normal beam incidence. The response of the dosimeter to assess the energy dependency was obtained as 2.2% at the radiation field of the 137Cs and 60Co beams. The dosimeter response was dependent on the bias-polarity, with maximum discrepancy of 11.1%. The dosimetry response was highly dependent upon the radiation field size. The repeatability of the dosimeter response was measured with standard deviation less than 1%. As well, the dosimeter response during the one-hour irradiation was stable with a standard deviation of 0.66%. Results showed that considering some correction factors, this material can be used for dosimetry of gamma-rays at the therapy level. [ABSTRACT FROM AUTHOR]

Nano-crystalline bismuth manganese oxide Bi2Mn4O10 was prepared from Bi2O3 and MnO2 by mechanochemical technique at different milling times followed by heat treatment at 1073 K. The crystal structural were obtained using X-ray diffraction (XRD) and TEM. We obtained the variation of the crystallite size and micro-strain with milling time. The magnetic parameters include the saturation magnetization, coercivity and squareness ratio were obtained by vibrating sample magnetometer (VSM). Each of the coercive field, Squareness ratio and saturation magnetization increased with increasing the milling time. The electrical conduction of the prepared samples was evaluated by AC conductivity measurements at different temperature, the dielectric parameters were plotted against temperature at different frequencies. The conduction mechanism is described by the correlated barrier hopping model (CBH). The recoverable energy density and loss energy was obtained to calculate the storage energy efficiency. [ABSTRACT FROM AUTHOR]

Catalytic conversion of methane to methanol is one of the most promising processes for effective natural gas resource utilization. In this work, Bi4O6-catalyzed oxidation of methane to methanol with N2O as an oxidizing reactant has been investigated by DFT calculation. For the overall reaction mechanism of three N2O molecules on Bi4O6 catalyst, two catalytic cycles were proposed. Cycle 1 involved the consecutive decomposition of the first two N2O molecules. Cycle 2 corresponded to the decomposition of the third N2O molecule. The activation barriers of the first and second N2O decomposition were computed to be 27.6 and 35.0 kcal/mol, respectively. The third N2O decomposition in cycle 2 required 36.1 kcal/mol activation barriers. Thus, cycle 1 was the main catalytic cycle for N2O as the cycle required lower in barriers than those of the other. Oxidation of methane to methanol on Bi4O7 and Bi4O8 catalysts was supposed to be a two-step mechanism consisting of H3C-H bond breaking and CH3-OH formation. The activation energies of the two steps were 32.7, 41.1, and 21.6, 17.2 kcal/mol for Bi4O7 and Bi4O8, respectively. Thus, methane oxidation over Bi4O8 was found to be more energetically favorable than those of Bi4O7, in which C–H bond breaking is the RDS. The present catalyst could be a promising material for the oxidation of methane to methanol. In summary, the single-site catalytic model study would be beneficial for guiding and searching for potential catalysts in heterogeneously catalyzed N2O decomposition and methanol synthesis as green as possible. However, theoretical investigation of this kind of catalyst's extended model system must be taken into account. [ABSTRACT FROM AUTHOR]

Catalytic conversion of methane to methanol is one of the most promising processes for effective natural gas resource utilization. In this work, Bi4O6-catalyzed oxidation of methane to methanol with N2O as an oxidizing reactant has been investigated by DFT calculation. For the overall reaction mechanism of three N2O molecules on Bi4O6 catalyst, two catalytic cycles were proposed. Cycle 1 involved the consecutive decomposition of the first two N2O molecules. Cycle 2 corresponded to the decomposition of the third N2O molecule. The activation barriers of the first and second N2O decomposition were computed to be 27.6 and 35.0 kcal/mol, respectively. The third N2O decomposition in cycle 2 required 36.1 kcal/mol activation barriers. Thus, cycle 1 was the main catalytic cycle for N2O as the cycle required lower in barriers than those of the other. Oxidation of methane to methanol on Bi4O7 and Bi4O8 catalysts was supposed to be a two-step mechanism consisting of H3C-H bond breaking and CH3-OH formation. The activation energies of the two steps were 32.7, 41.1, and 21.6, 17.2 kcal/mol for Bi4O7 and Bi4O8, respectively. Thus, methane oxidation over Bi4O8 was found to be more energetically favorable than those of Bi4O7, in which C–H bond breaking is the RDS. The present catalyst could be a promising material for the oxidation of methane to methanol. In summary, the single-site catalytic model study would be beneficial for guiding and searching for potential catalysts in heterogeneously catalyzed N2O decomposition and methanol synthesis as green as possible. However, theoretical investigation of this kind of catalyst's extended model system must be taken into account. [ABSTRACT FROM AUTHOR]

To eliminate the exposure of medical staff to radiopharmaceuticals during nuclear medicine tests, a new process technology was proposed for manufacturing gamma-ray shields used in nuclear medicine. In the case of manufacturing the existing gamma-ray shield, a method of increasing the content of the shielding material in the mixed material is used to improve the shielding performance. However, it is impossible to improve the shielding performance by simply increasing the content of the shielding material. Therefore, this study aims to present the optimal conditions for improving the miscibility between composite materials. Following the additional mixing of barium sulfate and bismuth oxide with tungsten, a syringe shield was developed via a plastic injection mold process. When tungsten was solely used or in combination with other shielding materials, polymer encapsulation occurred, and miscibility between composite materials was observed. Based on these results, the optimal conditions in terms of eco-friendly materials, economic feasibility, and improvement in shielding performance were determined. The findings of this study reveal that when tungsten and the polymers are combined, the polymer encapsulation is optimal, the particles are uniformly dispersed, and the shielding performance is significantly improved. With a 99mTc source, a 6.9% improvement in the shielding performance is achieved compared with the use of lead. [ABSTRACT FROM AUTHOR]

Nano-crystalline bismuth manganese oxide Bi2Mn4O10 was prepared from Bi2O3 and MnO2 by mechanochemical technique at different milling times followed by heat treatment at 1073 K. The crystal structural were obtained using X-ray diffraction (XRD) and TEM. We obtained the variation of the crystallite size and micro-strain with milling time. The magnetic parameters include the saturation magnetization, coercivity and squareness ratio were obtained by vibrating sample magnetometer (VSM). Each of the coercive field, Squareness ratio and saturation magnetization increased with increasing the milling time. The electrical conduction of the prepared samples was evaluated by AC conductivity measurements at different temperature, the dielectric parameters were plotted against temperature at different frequencies. The conduction mechanism is described by the correlated barrier hopping model (CBH). The recoverable energy density and loss energy was obtained to calculate the storage energy efficiency. [ABSTRACT FROM AUTHOR]

The gamma mass (µm) and linear (µ) attenuation coefficients of polycarbonate-bismuth oxide composites (PC-Bi2O3) with different bismuth oxide weight factors were investigated theoretically using EpiXS and a Monte Carlo simulation-based toolkit and Geant4 within an energy range between 0.1 and 2 MeV. The wide energy ranges of gamma rays and neutrons were chosen to cover as many applications as possible. The attenuation coefficients were then used to compute the half-value layers. The effective atomic numbers and effective electron densities of the studied samples obtained by EpiXS were compared as well. In order to further evaluate the shielding effectiveness of the studied samples, the thicknesses of all the investigated samples equivalent to 0.5 mm lead at a gamma energy of 511 keV were compared using a Geant4 code simulating a female numerical phantom with a gamma source placed facing the chest and a cylinder-shaped shield wrapped around the trunk area. The fast neutron removal cross sections of the investigated samples were studied to evaluate the effect of the weight factor of nanocomposites on the neutron shielding capabilities of the polymer as well. [ABSTRACT FROM AUTHOR]

The shuttling effect of soluble lithium polysulfides (LiPSs) and the sluggish conversion kinetics of polysulfides into insoluble Li2S2/Li2S severely hinders the practical application of Li-S batteries. Advanced catalysts can capture and accelerate the liquid–solid conversion of polysulfides. Herein, we try to make use of bismuth tantalum oxide with oxygen vacancies as an electrocatalyst to catalyze the conversion of LiPSs by reducing the sulfur reduction reaction (SRR) nucleation energy barrier. Oxygen vacancies in Bi4TaO7 nanoparticles alter the electron band structure to improve instinct electronic conductivity and catalytic activity. In addition, the defective surface could provide unsaturated bonds around the vacancies to enhance the chemisorption capability with LiPSs. Hence, a multidimensional carbon (super P/CNT/Graphene) standing sulfur cathode is prepared by coating oxygen vacancies Bi4TaO7−x nanoparticles, in which the multidimensional carbon (MC) with micropores structure can host sulfur and provide a fast electron/ion pathway, while the outer-coated oxygen vacancies with Bi4TaO7−x with improved electronic conductivity and strong affinities for polysulfides can work as an adsorptive and conductive protective layer to achieve the physical restriction and chemical immobilization of lithium polysulfides as well as speed up their catalytic conversion. Benefiting from the synergistic effects of different components, the S/C@Bi3TaO7−x coin cell cathode shows superior cycling and rate performance. Even under a high level of sulfur loading of 9.6 mg cm−2, a relatively high initial areal capacity of 10.20 mAh cm−2 and a specific energy density of 300 Wh kg−1 are achieved with a low electrolyte/sulfur ratio of 3.3 µL mg−1. Combined with experimental results and theoretical calculations, the mechanism by which the Bi4TaO7 with oxygen vacancies promotes the kinetics of polysulfide conversion reactions has been revealed. The design of the multiple confined cathode structure provides physical and chemical adsorption, fast charge transfer, and catalytic conversion for polysulfides. [ABSTRACT FROM AUTHOR]

The granulation of bismuth oxide (BO) by alginate (Alg) and the iodide adsorption efficacy of Alg–BO for different initial iodide concentrations and contact time values were examined. The optimal conditions for Alg–BO granulation were identified by controlling the weight ratio between Alg and BO. According to the batch iodide adsorption experiment, the Alg:BO weight ratio of 1:20 was appropriate, as it yielded a uniform spherical shape. According to iodide adsorption isotherm experiments and isotherm model fitting, the maximum sorption capacity (qm) was calculated to be 111.8 mg/g based on the Langmuir isotherm, and this value did not plateau even at an initial iodide concentration of 1000 mg/L. Furthermore, iodide adsorption by Alg–BO occurred as monolayer adsorption by the chemical interaction and precipitation between bismuth and iodide, followed by physical multilayer adsorption at a very high concentration of iodide in solution. The iodide adsorption over time was fitted using the intraparticle diffusion model. The results indicated that iodide adsorption was proceeded by boundary layer diffusion during 480 min and reached the plateau from 1440 min to 5760 min by intraparticle diffusion. According to the images obtained using cross-section scanning electron microscopy assisted by energy-dispersive spectroscopy, the adsorbed iodide interacted with the BO in Alg–BO through Bi–O–I complexation. This research shows that Alg–BO is a promising iodide adsorbent owing to its high adsorption capacity, stability, convenience, and ability to prevent secondary pollution. [ABSTRACT FROM AUTHOR]

High-temperature transformation of β-PtBi2, a synthetic analogue of insizwaite, was studied under oxidizing conditions (on air). The behavior of the sample upon heating up to 660°C and cooling was studied by differential thermal analysis (DTA) and high-temperature X-ray powder diffraction. It was shown that polymorphic transitions of β-PtBi2 into high-temperature γ- and δ-polymorphs do not occur under thermal treatment in the oxidizing conditions (on air). The DTA curve shows two exothermic peaks at 318 and 620°C. The total weight change in the temperature range studied is +10.5%. No thermal reactions or weight changes were recorded upon cooling of the sample. According to the high-temperature diffraction experiment in situ, the decomposition of the synthesized phase into Pt and Bi was recorded with their subsequent oxidation to bismuth oxide Bi2O3 with the bismite-type structure and double platinum and bismuth oxide with the pyrochlore-type structure Bi2Pt2O7. The study by electron microprobe analysis showed that the grains of the transformed insizwaite are a finely dispersed mixture of two oxides. [ABSTRACT FROM AUTHOR]

Zinc bismuthate/bismuth oxide nanocomposites have been prepared by one-step precipitation method. Zinc bismuthate/bismuth oxide nanocomposites were used as the electrode-modified materials for the benzoic acid electrochemical sensors. The electrochemical properties were analyzed by electrochemical impedance spectroscopy and cyclic voltammetric (CV) method. The results show that the intensity of the CV peaks increases obviously with the increase of benzoic acid concentration and scan rate. The sensor based on the zinc bismuthate/bismuth oxide nanocomposites shows a low detection limit of 0.053 µM at a signal-to-noise ratio of 3, a wide linear range of 0.0002–2 mM, good reproducibility, and stability. [ABSTRACT FROM AUTHOR]

BiOXs (X = Br, Cl, I, F) are extensively used visible-light-driven photocatalysts and used widely, but except for BiOF, they exhibit an indirect bandgap, and electrons need to cross the K layer to enter the conduction band, which greatly reduces electron–hole complexation. To enhance the photocatalytic activity of BiOXs, we prepared a series of BiOXs materials modified with mesoporous SiO2 using a hybrid solvothermal method with microwave assistance. It was demonstrated using XRD, SEM, XPS, UV–vis DRS, and PL methods that the two-dimensional layered BiOXs were successfully complexed with mesoporous SiO2 forming highly active photocatalysts. Under simulated visible-light conditions, the SiO2/BiOXs materials showed very high degradation efficiency for ofloxacin (OFL) and tetracycline hydrochloride (TCH). The photocatalytic degradation efficiency of both SiO2/BiOCl and SiO2/BiOBr for OFL and TCH was up to 100%. The enhanced activity of the photocatalyst was attributed to the formation of a heterogeneous interface between mesoporous SiO2 and two-dimensional layered bismuth halide oxides, thus improving the separation rate of photogenerated carriers. The introduction of mesoporous SiO2 provided more adsorption sites and active sites for antibiotic molecules improving the adsorption performance of BiOX. In addition, the quenching experiments showed that ·O2− was the main reactant for OFL and TCH. This study demonstrates feasible preparation of low-cost, simple, and efficient photocatalysts, offering promising application potential for photocatalytic degradation of antibiotic contaminants in water. [ABSTRACT FROM AUTHOR]

For extensive radiation exposure, inventing a novel radiation shielding material is a burning issue at present for the purpose of life saving. Considering this thought, in this study, by adding sundry amounts of Bi2O3 into pure high-density polyethylene (HDPE), six HDPE systems were prepared to evaluate the radiation shielding efficiency. These HDPE systems were HDPEBi-0 (pure HDPE), HDPEBi-10 (10 wt% Bi2O3), HDPEBi-20 (20 wt% Bi2O3−), HDPEBi-30 (30 wt% Bi2O3), HDPEBi-40 (40 wt% Bi2O3), and HDPEBi-50 (50 wt% Bi2O3). The values of the linear attenuation coefficients of the experimental results (calculated in the lab using HPGe) were compared with the theoretical results (obtained using Phy-X software) at 0.060, 0.662, 1.173, and 1.333 MeV energies. To ensure the accurateness of the experimental results, this comparison was made. It was crystal clear that for energy values from 0.06 MeV to 1.333 MeV, all the experimental values were in line with Phy-X software data, which demonstrated the research setup's reliability. Here, the linear attenuation coefficient (LAC), and mean free path (MFP) shielding parameters were assessed. At the energy of 1.333 MeV, sample HDPEBi-0 showed an HVL value 1.7 times greater than that of HDPEBi-50, yet it was 23 times greater at 0.0595 MeV. That means that for proper radiation protection, very-low-energy HDPE systems containing 10–50% Bi2O3 could be used; however, the thickness of the HDPE system must be increased according to the energy of incident radiation. [ABSTRACT FROM AUTHOR]