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BACKGROUND: Palladium nanoparticles can act as a shuttle to accelerate the extracellular electron transfer (EET) by exoelectrogens. Through the EET process, microorganisms drive the redox cycle of many substances. The palladium nanoparticle has a variety of catalytic activities and activities can be significantly improved by combining with the active effects of microorganisms. RESULTS: In this study, Staphylococcus saprophyticus JJ‐1 was utilized as a biological template carrier to synthesize palladium nanoparticles that were immobilized on the bacterial surface. The morphology and composition of palladium were characterized by various techniques including transmission electron microscopy, energy‐dispersive X‐ray spectroscopy, X‐ray diffraction, X‐ray photoelectron spectroscopy, and Fourier transform infrared spectroscopy. Furthermore, the hydrogenation activity of the synthesized Pd was tested at room temperature and atmospheric pressure using methyl orange as a model pollutant. Electrochemical characterization was carried out by cyclic voltammetry and potentiostatic measurements. The research demonstrated that palladium nanoparticles acted as both electronic mediators and catalysts in the dye reduction process, while S. saprophyticus JJ‐1 contributed to stabilizing nanoparticles and electrochemical activity. The synergistic effect between these two components significantly enhances MO degradation efficiency. CONCLUSION: This study presented an energy‐saving method to synthesize an integrated catalyst based on the synergistic interaction between biomass and nanoparticles, offering a novel approach for developing environmentally friendly, cost‐effective, and efficient integrated catalysts. © 2024 Society of Chemical Industry (SCI). [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this paper is to investigate the friction and wear mechanisms in copper-based self-lubricating composites with MoS2 as the lubricating phase, which provides a theoretical basis for subsequent research on high-performance copper-based self-lubricating materials. Design/methodology/approach: Friction tests were performed at a speed of 100 r/min, a load of 10 N, a friction radius of 5 mm and a sliding speed of 30 min. Friction experiments were carried out at RT-500°C. The phase composition of the samples was characterized by X-ray diffraction of Cu Ka radiation, and the microstructure, morphology and elemental distribution were characterized by scanning electron microscopy and energy dispersive spectroscopy. Reactants and valences formed during the wear process were analyzed by X-ray photoelectron spectroscopy. Findings: The addition of MoS2 can effectively improve friction-reducing and anti-wear action of the matrix, which is beneficial to form a lubricating film on the sliding track. After analyzing different changing mechanism of the sliding tracks, the oxides and sulfides of MoS2, MoO2, Cu2O, CuO and Ni(OH)2 were detected to form a synergetic lubricating film on the sliding track, which is responsible for the excellent tribological properties from room to elevated temperature. Research limitations/implications: For self-lubrication Cu–Sn–Ni–MoS2 material in engineering field, there are still few available references on high-temperature application. Practical implications: This paper provides a theoretical basis for the following research on copper-based self-lubricating materials with high performance. Originality/value: With this statement, the authors hereby certify that the manuscript is the results of their own effort and ability. They have indicated all quotes, citations and references. Furthermore, the authors have not submitted any essay, paper or thesis with similar content elsewhere. No conflict of interest exits in the submission of this manuscript. [ABSTRACT FROM AUTHOR]

This study presents the synthesis and characterization of composite material comprised of NiFe2O4 and CuO. The preparation of this composites involves a facile and cost-effective co-precipitation method, followed by heat treatment. The aim of this study is to explore the potential of this composite material for various catalytic applications. The synthesized NiFe2O4/CuO composites were extensively characterized using various analytical techniques, including X-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier-transform infrared spectroscopy (FTIR), impedance analyzer, UV-Visible spectroscopy (UV-Vis.), Brunner–Emmett–Teller (BET), and X-ray photoelectron spectroscopy (XPS). These characterizations revealed the successful formation of a nanocomposite material with a well-defined structure and identified the oxygen vacancies/defects in the samples which might result in enhanced photocatalytic efficiency. Photocatalytic activity of 0.5NiFe2O4/0.5CuO composite showed degradation of methylene blue dye by 96.15% in 120 min. This work is not only to understand the photocatalytic mechanism but also to develop effective catalysts for the degradation of harmful organic pollutants. [ABSTRACT FROM AUTHOR]

A composite of manganese sulfide doped iron oxychloride (MnS-FeOCl) was successfully synthesized for the first time and applied to activate H2O2 to degrade isoniazid under different pH values. The MnS-FeOCl structure was characterized by various analytical methods such as X-ray diffraction (XRD), scanning electron microscopy, energy-dispersive X-ray spectroscopy, Fourier-transform infrared spectroscopy and X-ray photoelectron spectroscopy, indicating manganese sulfide (MnS) doping greatly changed the physicochemical property of FeOCl. The Fenton-like reaction showed that MnS doping could enhance the Fenton activity of FeOCl in the pH range of 6-9, and 5% MnS-FeOCl composite had the highest activity. Isoniazid (20 mg/L) could be degraded by 89.90% in 5 min at an initial pH of 6.0 by 5% MnS-FeOCl/H2O2. However, the high performance of 5% MnS-FeOCl composite was at the cost of decrease of its stability. The result of XRD analysis indicated that the crystallinity of 5% MnS-FeOCl was poorer than that of pristine FeOCl, thus leading to its decreased stability. It is of great significance for the further study on the modification of FeOCl catalyst in Fenton-like reaction. [ABSTRACT FROM AUTHOR]

This study reports on the synthesis and characterization of a series of lithium gallate (LiGa5O8) phosphors doped with varying concentrations of Eu3+ ions. X-ray powder diffraction analysis confirmed the synthesis of the cubic phase of LiGa5O8, with additional peaks corresponding to Eu2O3 at higher dopant concentrations. Rietveld refinement confirmed the formation of a spinel-structured host with a space group of P4322. Ultraviolet-visible spectroscopy was used to analyze the absorption properties of the phosphor material and estimate the bandgap for all synthesized samples, which ranged from 4.75 to 4.95 eV, indicating the formation of a wide bandgap semiconductor stable at room temperature. Morphological and compositional analysis, along with surface mapping, were conducted using field emission scanning electron microscopy, energy dispersive electron spectroscopy, and time-of-flight secondary ion mass spectroscopy. X-ray photoelectron spectroscopy provided insights into the crystal structure and revealed the presence of oxygen vacancies and some other crystal defects. Photoluminescent properties were examined through photoluminescence excitation and emission spectra for all doped samples. Notably, samples doped with 6 and 7 mol% Eu3+ displayed a prominent excitation peak at 247 nm corresponding to the presence of Eu2O3, while the remaining samples exhibited characteristic Eu3+ excitation. Lifetime measurements for both excitation wavelengths showed decay times in the millisecond range. The emission color of all samples resided within the red region of the electromagnetic spectrum, boasting remarkable color purity. The results suggest that this material has potential as a red light-emitting component for LED applications. [ABSTRACT FROM AUTHOR]

A novel non-solvent displacement-nonaqueous precipitation method was developed for the preparation of core-shell materials by considering C@ZrSiO 4 black pigments synthesis as the case. The effects of the impregnation time, precursor concentration, and carbon content on the synthesis and coloration of the C@ZrSiO 4 pigment and the mechanism of this method were investigated via X-ray diffraction, transmission electron microscopy, field-emission scanning electron microscopy, Fourier-transform infrared spectroscopy, X-ray photoelectron spectroscopy, Raman spectroscopy, and CIELAB colorimetry. The results showed that the optimal impregnation time, precursor concentration, and carbon content were 24 h, 1.5 mol/L, and 9 wt%, respectively. C@ZrSiO 4 -encapsulated pigments prepared by a non-solvent displacement-nonaqueous precipitation method have a uniform and dense shell-encapsulated zircon layer with a thickness of 10–20 nm. The size of C@ZrSiO 4 encapsulated pigments was 50–210 nm, without particle agglomeration. This uniform and dense encapsulation facilitated an excellent color-rendering effect in the high-temperature glaze, and the chromaticity values of the glaze were L* = 35.05, a* = 0.34, and b* = 1.08. The alkyl halide elimination non-hydrolytic heterocondensation reaction ensured the formation of a uniform precipitate along the surface of the carbon particles with Si–O–Zr bonds as the skeleton. The introduction of the non-solvent kerosene ensured the complete, uniform, and dense progress of the precipitation process to form a C@ZrSiO 4 pigment with a high-quality core-shell structure. The non-solvent displacement-nonaqueous precipitation method might be an extremely promising method for preparing core-shell structural materials. [ABSTRACT FROM AUTHOR]

Polyaniline (PANI) is a promising conducting polymer for surface modification of TiO2 to overcome limitations of the use of visible light and attain increased photocatalytic efficiency for the removal of organic contaminants. In this study, a series of polyaniline modified TiO2 (PANI-TiO2) composites were prepared by using "in-situ" chemical oxidation polymerization method. The composites were systematically characterized by Fourier transform infrared spectroscopy (equipped with an attenuated total reflection accessory, FTIR-ATR), Raman spectroscopy, X-ray diffractometry (XRD), scanning electron microscopy coupled with energy dispersive X-ray spectroscopy (SEM-EDAX), X-ray photoelectron spectroscopy (XPS), ultraviolet–visible diffuse reflectance spectroscopy (UV-DRS), photoluminescence spectroscopy (PL), nitrogen (N2) physisorption (Brunauer − Emmett − Teller surface area (SBET) and Barrett-Joyner-Halenda (BJH) pore size analysis), thermogravimetry-derivative thermogravimetry (TG-DTG) techniques. XRD patterns of PANI-TiO2 composites confirmed both the amorphous phase of PANI and the crystalline character of TiO2. TG/DTG analysis complemented the XRD profiles that the interactions between PANI and TiO2 resulted in a more stable PANI-TiO2 matrix. SEM images displayed the dominant morphology as dandelion-like shapes of PANI being more pronounced with increasing PANI ratios in PANI-TiO2 composites. UV-DRS profiles revealed that the band gap energies of the composites were lower than bare TiO2 expressing a shift to the visible light region. Both PL and UV-DRS analyses confirmed the band-gap reduction phenomenon of PANI modification of TiO2. The incorporation of PANI into TiO2 resulted in a reduction of the surface area of TiO2. The composites were subsequently subjected to photocatalytic activity assessment tests using humic acid (HA) as a model of refractory organic matter (RfOM) under simulated solar irradiation (Uyguner-Demirel et al. Environ Sci Pollut Res 30 85626-85638, 2023). The morphological and structural changes attained upon application of photocatalysis were also evaluated by FTIR-ATR, Raman spectroscopy, XRD, and SEM-EDAX methods in a comparable manner. The FTIR-ATR spectral features of PANI, RfOM and all composites displayed peaks with slight shifts under pre- and post- photocatalytic conditions as well as following dark surface interactions. Besides exhibiting noticeable photocatalytic performance, PANI-TiO2 composites were also proven to maintain stability under non-selective oxidation conditions in the presence of a complex organic matrix. The prepared PANI-TiO2 composites overcoming the limitations of UVA light active bare TiO2 photocatalysis could possibly find a beneficial use as potential catalysts in solar photocatalytic applications. [ABSTRACT FROM AUTHOR]

Graphene has been hailed by scientists as the "wonder material" of the 21st century. Despite the impressive mechanical and electrical qualities of graphene in its unprocessed state, graphene‐based epoxy nanocomposites can only be used as a structural material on a small scale. The random dispersion and orientation of graphene in epoxy cause the failure. Magnetite Fe3O4 nanoparticles are synthesized and solvo‐thermally attached to the graphene nanoplatelets (GNP) surfaces in order to utilize our recently model's suggested optimized alignment parameters. Solution with properly dispersed nanoparticles, that is, Fe3O4‐GNP within epoxy, is exposed to the magnetic field (0.05 T). Morphology, microstructure, and magnetic properties of GNP, Fe3O4, and Fe3O4‐GNP nanoparticles have been characterized by X‐ray diffraction, Fourier‐transform infrared spectroscopy, Raman spectroscopy, thermogravimetric analysis, differential scanning calorimetry, atomic force microscopy, X‐ray photoelectron spectroscopy, Brunauer–Emmett–Teller, transmission electron microscopy, scanning electron microscopy, energy‐dispersive X‐ray microanalysis, and vibrating sample magnetometry. The aforementioned characterization method, optical microscopy, and studying the fracture surface morphology confirmed the alignment. The fabricated aligned Fe3O4‐GNP nanocomposite is best used as a functional material. [ABSTRACT FROM AUTHOR]

Polymeric surfaces have been increasingly plasma-activated to adopt adequate chemistries, enabling their use in different applications. An unavoidable surface oxygen insertion upon exposure to non-oxygen-containing plasmas was always observed and mainly attributed to in-plasma oxidation stemming from O2 impurities in plasma reactors. Therefore, this work investigates exclusive in-plasma oxidation processes occurring on polyethylene surfaces by purposely admixing different O2 concentrations to medium-pressure Ar and N2 dielectric barrier discharges (base pressure: 10−7 kPa). Hence, distinctive optical emission spectroscopy and in-situ X-ray photoelectron spectroscopy (XPS) data were carefully correlated. Pure N2 discharge triggered an unprecedented surface incorporation of large nitrogen (29%) and low oxygen (3%) amounts. A steep rise in the O-content (10%) at the expense of nitrogen (15%) was detected upon the addition of 6.2 × 10−3% of O2 to the feed gas. When the added O2 exceeded 1%, the N content was completely quenched. Around 8% of surface oxygen was detected in Ar plasma due to high-energy Ar metastables creating more surface radicals that reacted with O2 impurities. When adding only 6.2 × 10−3% of O2 to Ar, the surface O content considerably increased to 12%. Overall, in-plasma oxidation caused by O2 impurities can strikingly change the surface chemistry of N2 and Ar plasma-treated polymers. [ABSTRACT FROM AUTHOR]

MnO2 is widely utilized as a vulcanizing agent for polysulfide (PS) sealing; however, it is difficult to flexibly adjust the vulcanizing process while keeping costs low. Herein, we successfully prepared α-MnO2, γ-MnO2 and δ-MnO2, as characterized by X-ray diffractometry, scanning electron microscopy, transmission electron microscopy, energy-dispersive X-ray spectroscopy mapping and X-ray photoelectron spectroscopy, and found for the first time that the photogenerated carriers on MnO2 can trigger the free radical attack of –SH under visible light, leading to rapid, efficient and controllable PS sealing. Furthermore, the effect of different treatment conditions, crystalline form, and light power density on the curing rate was investigated. δ-MnO2 showed better PS sealing performance under irradiation of 1140 mW cm−2 than under natural light and dark conditions, and δ-MnO2 showed a higher curing rate than those of α-MnO2 and γ-MnO2. Moreover, the curing rate increased with an increase in the light power density. The induction time and curing rate can be flexibly controlled by adjusting the optical power density and turning the light on/off. Furthermore, the effect of illumination uniformity on rubber surface shape was investigated, and a sample with a flat surface was obtained under uniform illumination. In addition, two pathways of photocatalytic initiation and the traditional PS oxidation radical mechanism for polysulfide sealing over δ-MnO2via photo-assistance were proposed. This study details a novel, facile and general strategy to achieve rapid, efficient and controllable PS sealing in industrial settings. [ABSTRACT FROM AUTHOR]

MnO2 is widely utilized as a vulcanizing agent for polysulfide (PS) sealing; however, it is difficult to flexibly adjust the vulcanizing process while keeping costs low. Herein, we successfully prepared α-MnO2, γ-MnO2 and δ-MnO2, as characterized by X-ray diffractometry, scanning electron microscopy, transmission electron microscopy, energy-dispersive X-ray spectroscopy mapping and X-ray photoelectron spectroscopy, and found for the first time that the photogenerated carriers on MnO2 can trigger the free radical attack of –SH under visible light, leading to rapid, efficient and controllable PS sealing. Furthermore, the effect of different treatment conditions, crystalline form, and light power density on the curing rate was investigated. δ-MnO2 showed better PS sealing performance under irradiation of 1140 mW cm−2 than under natural light and dark conditions, and δ-MnO2 showed a higher curing rate than those of α-MnO2 and γ-MnO2. Moreover, the curing rate increased with an increase in the light power density. The induction time and curing rate can be flexibly controlled by adjusting the optical power density and turning the light on/off. Furthermore, the effect of illumination uniformity on rubber surface shape was investigated, and a sample with a flat surface was obtained under uniform illumination. In addition, two pathways of photocatalytic initiation and the traditional PS oxidation radical mechanism for polysulfide sealing over δ-MnO2via photo-assistance were proposed. This study details a novel, facile and general strategy to achieve rapid, efficient and controllable PS sealing in industrial settings. [ABSTRACT FROM AUTHOR]

MoS2 thin films were grown by the pulsed laser deposition technique using a picosecond laser at a wavelength of 1030 nm. The plasma ion mean kinetic energy and density were estimated from the time-of-flight distributions measured using a Langmuir planar probe. It has been found that the mean kinetic energy decreases with increasing the laser pulse energy. This unusual effect is explained by the difference in the volatility of the vaporized species. Samples were structurally characterized by Raman spectroscopy and grazing angle X-ray diffraction. It was found that thin films of amorphous matrices containing MoS2 nanocrystallites were grown. Optical characterization carried out by UV-vis spectroscopy yielded transmittance values above 90% in the visible spectral range and an indirect electronic transition at 1.4 eV. Chemical oxidation states for molybdenum and sulfur were analyzed by means of X-ray photoelectron emission spectroscopy, which revealed Mo-S bonding states, confirming the growth of MoS2. [ABSTRACT FROM AUTHOR]

Novel Fe3O4/maifan stone composite were prepared by a simple solvothermal method. Physicochemical properties of the novel Fe3O4/maifan stone composite were analyzed using energy-dispersive X-ray spectroscopy, X-ray diffraction, scanning electron microscopy, transmission electron microscopy, N2 adsorption, Fourier-transform infrared spectroscopy and X-ray photoelectron spectroscopy. The Fe3O4/maifan stone composite were used for the adsorption of ciprofloxacin (CIP) antibiotic removal. This paper represents an artificial neural network (ANN) based approach for modeling the adsorption process of the adsorption of CIP onto Fe3O4/maifan stone composite in batch adsorption experiments. The ANN model was trained and validated with the adsorption experiments data where pH, adsorbent dosage, and initial CIP concentration were selected as the variables for the batch study, whereas the removal efficiency was considered as the output. The ANN model was first developed using a three-layer back-propagation network with the optimum structure of 3-3-1. The model employed tangent sigmoid transfer function as input in the hidden layer whereas a linear transfer function was used in the output layer. The comparison between modeled data and experimental data provided high degree of correlation (R² = 0.99942) which indicated the applicability of ANN model for describing the adsorption process with reasonable accuracy. The kinetics of the adsorption of CIP onto Fe3O4/maifan stone composite was better fitted with the pseudo-second-order kinetics model, and thermodynamic parameters of the adsorption of CIP onto Fe3O4/maifan stone composite were calculated. This Fe3O4/maifan stone composite adsorbent can be easily separated. [ABSTRACT FROM AUTHOR]

Nanoarchitecture in naturally occurring materials has always fascinated man tempting him to mimic them and explore the mystery behind their unparallel physical, structural, optical, thermal, and pharmacological properties. The paper scientifically validates the unknown composition of the Eumeninae wasp nest (EWN) exhibiting exceptional thermophysical and pharmacological properties. The Eumeninae wasp nest is subjected to various structure, elemental, and morphological characterizations by X-ray diffraction, X-ray photoelectron spectroscopy, inductively coupled plasma mass spectrometry, and field emission scanning electron microscopy. Having understood the nanoarchitecture with the constituent elements, the electrical and thermal behaviour of the sample are also studied. The sample is closely similar to lateritic soil seen at the location where the nest sample is collected. The pharmacological potential of EWN is also unveiled through antibacterial, antifungal, and cytotoxicity studies. [ABSTRACT FROM AUTHOR]

Chemical vapor deposition (CVD) is an effective method for the growth of large scale two-dimensional materials. However, high density of vacancy defects are inevitably generated in the CVD process, which affects the photoelectric properties of the materials. In this work, millimeter-scale and atomic-thick WS2 membranes were directly grown on p-type Si (111) substrates using an alkali metal halide-assisted CVD method. Er-doped WS2 films ( WS2 ( Er)) were achieved by adding saturated ErCl 3 powders in the tungsten sources. Optical microscopy, scanning electron microscopy, atomic force microscopy, X-ray photoelectron spectroscopy, energy dispersive X-ray spectroscopy, photoluminescence and Raman spectroscopy techniques were used to characterize the materials systematically. The results show that the fluorescence intensity of WS2 (Er) films increase by an order of magnitude compared to pristine WS2, and the central wavelength is significantly redshifted. Fluorescence tests show that the fluorescence characteristics of WS2 grown on Si substrates show a significant charge transfer effect compared to that of WS2 on SiO2 substrates. The photoelectric test results of WS2 and WS2 (Er) field effect transistors based on SiO2 substrate show that the optical responsiveness of WS2 (Er) field effect transistors is 4. 015 A/ W, and the external quantum efficiency is 784%, both of which are more than 2 000 times that of pristine WS2 devices under the same conditions. This work has significance for research of rare earth doping in 2D materials. [ABSTRACT FROM AUTHOR]

Electrodeposition from an environmentally friendly iron sulfate electrolyte with citric acid as carbon source has gained attention recently, because of excellent mechanical properties of the resulting Fe–C coatings with intentionally codeposited high‐carbon concentrations. While being very attractive as protective coatings and sustainable alternatives for hard chrome coatings, comprehensive understanding of the coatings' chemical constitution including the type and location of carbon‐containing phases is still lacking. The amount of codeposited carbon of up to about 0.8 wt.% significantly exceeds the solubility of carbon in ferrite, although carbon‐free ferrite is the only unambiguously reported phase in as‐deposited Fe–C coatings so far. In the present work, time‐of‐flight secondary ion mass spectrometry, X‐ray photoelectron spectroscopy, and soft X‐ray emission spectroscopy have been applied to identify the carbon‐containing phases, which are present as minor secondary phases in the coatings but are known to have an important influence on the coatings' properties. Three carbon‐containing phases could be distinguished, homogeneously distributed in the nanocrystalline ferrite base material. Iron acetates, amorphous carbon, and carbides were found in both as‐deposited and annealed Fe–C coatings up to 300°C, but their fraction changes during postdeposition annealing. [ABSTRACT FROM AUTHOR]

In the present work, thermally evaporated Cu-poor CuSbS2 (Copper antimony disulphide—CAS) thin films are prepared with the precursor of Cu-poor CuSbS2 alloys. X-ray diffraction, Raman spectroscopy, X-ray photoelectron spectroscopy, field emission scanning electron microscopy, and UV–Visible spectroscopy have been used to characterise the prepared films to determine their potentiality as absorber layer materials for photovoltaic applications. By replacing the standard window layer of i-ZnO (intrinsic-zinc oxide) with one-dimensional (1D) n-type TiO2 (titanium dioxide) and an active layer of stoichiometry-adjusted CAS, we investigated the effect of architecture on photovoltaic (PV) performance. Solar cells with Cu-poor and stoichiometric-adjusted CAS absorbers have a Voc of 189 mV and a Jsc of 0.737 mA/cm2. The designed solar cell device with the structure FTO/TiO2/CdS/CAS/Al has a power conversion efficiency (PCE) of > 1%. [ABSTRACT FROM AUTHOR]

Bimetallic MOFs offer many advantageous properties rather than monometallic MOFs useful for variety of applications including energy storage and conversion, catalysis, gas separation, sensing, etc. Desired morphology with precise control of crystal size is of utmost importance for specific applications. Microfluidics-incorporated continuous synthesis is demonstrated for bimetallic ZIF-8/67 exhibiting significant nanocrystallinity, porosity and surface area. The microfluidic approach of synthesizing MOF is found very time-efficient in comparison with the conventional techniques. Bimetallic ZIF-8/67 samples were synthesized at different reaction conditions, without adding capping agents and modulators, followed by sophisticated characterization techniques including powder X-ray diffraction, field emission scanning electron microscopy, transmission electron microscopy, energy-dispersive spectroscopy, X-ray photoelectron spectroscopy, thermogravimetric analysis, Brunauer–Emmett–Teller analysis and Fourier transform infrared spectroscopy. [ABSTRACT FROM AUTHOR]

Green synthesis is a viable solution for maintaining industrial ecology and promoting sustainable development. Plant-based product design is a practical way to foresee the global trend in research. In this context, the synthesis of CuO nanoparticles (NPs) using Lippia abyssinica (Var. adoensis) leaf extract (CuO-L) and seed extract (CuO-S) is significant. In this study, first, phytochemical screening is performed to detect the reducing and stabilizing agents in the selected plant leaves and seed extracts. Subsequently, CuO NPs are prepared via simple green biosynthesis. The morphology and physicochemical and optical properties of the as-synthesized materials are assessed using X-ray diffraction analysis, scanning-electron microscopy, energy-dispersive X-ray photoelectron spectroscopy, Brunauer–Emmett–Teller analysis, differential reflectance spectroscopy, and photoluminescence measurements. The synthesized NPs are monoclinic with high crystallinity but have different sizes around 10–25 nm and bandgap energies of 1.473 and 1.481 eV for the leaf and seed-induced CuO NPs, respectively. Their photocatalytic activity is tested against that of the most prominent antibiotic, tetracycline. The leaf-induced CuO NPs exhibited relatively high photocatalytic catalytic activity. [ABSTRACT FROM AUTHOR]

The development of photocatalyzed water remediation strategies using visible (solar) light to mineralize volatile chlorinated organic compounds (VCOCs) is a long standing, not yet fully achieved goal. Herewith, a facile route is presented to synthesize vanadium‐doped TiO2 photocatalysts using a one‐step hydrothermal method. Different characterization methods are employed to investigate the physicochemical properties of as‐prepared V‐doped TiO2 samples, indicating the mixed phases of anatase, rutile, and brookite in the crystal structure addition to the mesoporous framework. The nature of the vanadium species at the TiO2 surface is assessed by X‐ray photoelectron and emission spectroscopy. The aerobic photodegradation of a common VCOC, trichloroethylene, using V‐doped catalysts is demonstrated to be much more effectively than with undoped TiO2. Importantly, the herein described V‐doped photocatalysts show high activity both under ultraviolett and visible light irradiation. Moreover, these V‐doped TiO2 photocatalysts are robust under the reaction conditions, being recyclable for at least four consecutive runs without any activity loss. [ABSTRACT FROM AUTHOR]

In this study, a new type of ceramic composite (PZSC/ZnO) was successfully synthesized using N, P, and S co‐doped carbon microspheres derived from polyphosphazene with zinc oxide. The morphology and structure were characterized by Fourier transform infrared spectroscopy, X‐ray photoelectron spectroscopy, scanning electron microscopy, energy‐dispersive spectroscopy, Raman, X‐ray diffraction, BET, and thermogravimetric. Batch experiments were used to explore the adsorption performance under different pH values, initial concentrations, contact times, and temperatures. The results showed that the maximum adsorption capacity of the PZSC/ZnO ceramic composite for uranium was 470.5 mg/g (pH = 5.5, t = 40 min, and T = 25°C). The adsorption process followed the nonlinear Langmuir model and the pseudo‐second‐order kinetic model, demonstrating that the monolayered combination of U(VI) with the PZSC/ZnO ceramic composite and the adsorption mechanism was chemical adsorption. Thermodynamic data revealed that the adsorption was a spontaneous endothermic process. Furthermore, P and N may be involved in the adsorption of uranyl ions through binding to the O atoms from ZnO. The main forces between U(VI) and the PZSC/ZnO ceramic composite were attributed to ZnO and heteroatoms doped in the material. [ABSTRACT FROM AUTHOR]

The current study reports nanostructured CaTiO 3 powder produced by two different novel modified sol-gel methods. The chemical reaction between the calcium oxide (CaO) extracted from chicken eggshell (ES) and titanium (IV) isopropoxide (TTIP) leads to the synthesis of calcium titanate nanopowder. Further leaf extract has also been added in one method which shows the significant effect to reduce particle size up to a certain extent. X-ray diffraction (XRD) and field-emission scanning electron microscopy (FE-SEM) were examined to confirm the nanometric particle size. Further, the crystalline structure and phase involvement were also investigated by Rietveld refinement. Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), ultraviolet–visible (UV–Vis), and photoluminescence spectra (PL) characterization were used to study the functional groups, elemental composition, and optical properties of the material. The photoluminescence emission that occurred in the sample was due to the distortion between [TiO 6 ] – [TiO 6 ] complex clusters causing a difference in the charge density, which can promote a charge transfer between these clusters. The CIE chromaticity coordinates were determined and it shows that the synthesized sample is a promising candidate for the blue color phosphor application. The present phosphors were highly useful for UV chip excited white LED applications. [Display omitted] [ABSTRACT FROM AUTHOR]

Silicon nano- and microparticles obtained using electric-spark dispersion of silicon electrodes and granules in 40 wt% solution of methyl alcohol in water were investigated by ultrasoft X-ray emission spectroscopy, X-ray photoelectron spectroscopy, X-ray diffraction, scanning and transmission electron microscopies. In addition, the SiLα spectra of obtained silicon particles were modeled by superimposing the spectra of pure silicon and silicon oxide taken in certain weight ratios. It was found that the surfaces of Si nano- and microparticles obtained in 40 wt% solution of methyl alcohol in water are covered with silicon oxide and chemisorbents, while the core consists of crystalline silicon with a cubic face-centered lattice. The silicon nano- and microparticles show potential as an anode material to replace commonly used graphite electrodes. The charge capacity of the electrode based on mixture of Si nano- and microparticles with graphite powder was about 1272 mAh/g after ten cycles. [ABSTRACT FROM AUTHOR]

Water splitting into hydrogen and oxygen is a promising method for storing sustainable but intermittent energies. Ruthenium compounds are promising for the water-oxidation reaction. Herein, an easy method is employed to load a water-oxidation catalyst (Ruthenium Red; ([(NH 3) 5 RuORu(NH 3) 4 ORu(NH 3) 5 ]Cl 6)) on the surface of the Escherichia coli bacterial template. After the synthetic procedure, the catalyst is characterized by field emission-scanning electron microscopes, high-resolution transmission electron microscopy, visible spectroscopy, X-ray photoelectron spectroscopy, Raman spectroscopy, and diffuse reflectance infrared Fourier transform spectroscopy. Some of the employed methods show that the bacterial template is intact after the synthetic procedure. In the next step, the catalyst is investigated by linear sweep, cyclic, and square wave voltammetry methods. The water-oxidation reaction of the compounds is examined under electrochemical conditions in LiClO 4 (0.25 M) at pH = 6.3. Linear sweep voltammetry shows that the onset overpotential of the water-oxidation reaction of the catalyst is 720 mV (based on extrapolation of the Tafel plot) with a Tafel slope of 226.4 mV per decade. Thus, the presence of Ruthenium Red in the material remarkably increases the activity of the water-oxidation reaction. [Display omitted] • Ruthenium compounds are among the most efficient water-oxidizing catalysts. • Escherichia coli bacterial template/Ruthenium Red is synthesized and characterized. • The electrochemical properties and oxygen-evolution reaction in the presence of this material were investigated. [ABSTRACT FROM AUTHOR]

Polystyrene (PS) was modified by covalently binding P-, P-N- and/or N- containing fire-retardant moieties through co- or ter-polymerization reactions of styrene with diethyl(acryloyloxymethyl)phosphonate (DEAMP), diethyl-p-vinylbenzyl phosphonate (DEpVBP), acrylic acid-2-[(diethoxyphosphoryl)methylamino]ethyl ester (ADEPMAE) and maleimide (MI). In the present study, the condensed-phase and the gaseous-phase activities of the abovementioned fire retardants within the prepared co- and ter-polymers were evaluated for the first time. Pyrolysis–Gas Chromatography/Mass Spectrometry was employed to identify the volatile products formed during the thermal decomposition of the modified polymers. Benzaldehyde, α-methylstyrene, acetophenone, triethyl phosphate and styrene (monomer, dimer and trimer) were detected in the gaseous phase following the thermal cracking of fire-retardant groups and through main chain scissions. In the case of PS modified with ADEPMAE, the evolution of pyrolysis gases was suppressed by possible inhibitory actions of triethyl phosphate in the gaseous phase. The reactive modification of PS by simultaneously incorporating P- (DEAMP or DEpVBP) and N- (MI) monomeric units, in the chains of ter-polymers, resulted in a predominantly condensed-phase mode of action owing to synergistic P and N interactions. The solid-state 31P NMR spectroscopy, Scanning Electron Microscopy/Energy Dispersive Spectroscopy, Inductively-Coupled Plasma/Optical Emission Spectroscopy and X-ray Photoelectron Spectroscopy of char residues, obtained from ter-polymers, confirmed the retention of the phosphorus species in their structures. [ABSTRACT FROM AUTHOR]

In this study, the colour anodising of a Ti-6Al-4V alloy in 0.05 M H3PO4 was investigated in the voltage range of 40–100 V. The Ti-6Al-4V substrates were anodised under two initial surface conditions: ground and unground. By means of ground samples, the native oxide layer was removed before anodising using conventional mechanical grinding techniques. After anodising, the changes in surface chemistry and topography were evaluated by performing Field Emission Scanning Electron Microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy. Depending on the initial surface finish (ground and unground) and the anodising voltage, different interference colours were obtained on the anodised surfaces. At low anodising voltages, the surfaces displayed relatively compact structures whereas higher voltages resulted in the formation of porosity, cracks, and blisters in both conditions. These changes also influenced the corrosion behaviour. The samples which were ground prior to anodising exhibited higher resistance to corrosion compared to the unground samples. [ABSTRACT FROM AUTHOR]

The azo dyes Reactive Orange‐16 and Reactive Green‐19 were removed using Aliquat‐336‐incorporated Amberlite XAD7HP resin in batch and in a continuous stirrer vessel. The prepared resin was characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, energy‐dispersive X‐ray spectroscopy, Brunauer‐Emmett‐Teller method, and X‐ray photoelectron spectroscopy. The effect of dosage, initial dye concentration, time, pH, and temperature on the removal efficiency of both dyes was evaluated. Equilibrium, kinetic, and diffusion models were fitted to the batch data. Design calculations for single‐stage batch adsorption were done to scale up the process industrially. The resin was regenerated using ethanol. To intensify the process further, continuous studies were performed in a recirculating stirred vessel at different flow rates and stirring speeds. [ABSTRACT FROM AUTHOR]

Fe2O3/TiO2 nanocomposites were fabricated via a facile impregnation/calcination technique employing different amounts iron (III) nitrate onto commercial TiO2 (P25 Aeroxide). The as-prepared Fe2O3/TiO2 nanocomposites were characterized by X-ray diffraction (XRD), Raman spectroscopy (RS), scanning electron microscopy/energy-dispersive spectroscopy (SEM/EDXS), X-ray photoelectron spectroscopy (XPS), Brunauer–Emmett–Teller analysis (BET), electron impedance spectroscopy (EIS), photoluminescence spectroscopy (PL), and diffuse reflectance spectroscopy (DRS). As a result, 5% (w/w) Fe2O3/TiO2 achieved the highest photocatalytic activity in the slurry system and was successfully immobilized on glass support. Photocatalytic activity under visible-light irradiation was assessed by treating pharmaceutical amoxicillin (AMX) in the presence and absence of additional oxidants: hydrogen peroxide (H2O2) and persulfate salts (PS). The influence of pH and PS concentration on AMX conversion rate was established by means of statistical planning and response surface modeling. Results revealed optimum conditions of [S2O82−] = 1.873 mM and pH = 4.808; these were also utilized in presence of H2O2 instead of PS in long-term tests. The fastest AMX conversion possessing a zero-order rate constant of 1.51 × 10−7 M·min−1 was achieved with the photocatalysis + PS system. The AMX conversion pathway was established, and the evolution/conversion of formed intermediates was correlated with the changes in toxicity toward Vibrio fischeri. Reactive oxygen species (ROS) scavenging was also utilized to investigate the AMX conversion mechanism, revealing the major contribution of photogenerated h+ in all processes. [ABSTRACT FROM AUTHOR]

Polyaspartic acid is considered a green agent for the treatment of circulating cooling water. However, its chemosynthetic process is not green, as it requires significant amounts of energy and causes water pollution. In this work, we identified an analog of polyaspartic acid, namely polyglutamic acid (γ-PGA), which could be directly produced by Bacillus spp., and we explored its performance and scale inhibition mechanism as a scale inhibitor. We found that γ-PGA secreted by B. megaterium with a molecular weight of ~ 70 kDa showed poor scale inhibition, while the γ-PGA secreted by B. licheniformis with a molecular weight of ~ 15 kDa had a 26.87% higher efficiency compared to commercially available polyaspartic acid. The scale inhibition mechanism was explored using the γ-PGA material secreted by B. licheniformis. Fourier transform spectrometer, field emission scanning electron microscopy, and X-ray photoelectron spectroscopy analysis demonstrated that the scale inhibition performance of γ-PGA was due to the combination of its functional groups and Ca2+, which affected the growth process of CaCO3 and inhibited the formation of CaCO3. This study provided deeper insight into scale inhibition performance related to the scale inhibition mechanism. [ABSTRACT FROM AUTHOR]

Herein, novel monodisperse basic magnesium sulfate whiskers (5Mg(OH)2·MgSO4·7H2O) were prepared under low-temperature and atmospheric-pressure conditions, using the admixture sodium citrate. X-ray diffraction, Raman spectroscopy, scanning electron microscopy, energy-dispersive spectroscopy, transmission electron microscopy, selected area electron diffraction, thermogravimetric analysis, Fourier-transform infrared spectroscopy, and X-ray photoelectron spectroscopy were used to characterize the structure and morphology of the whisker products. The analysis results showed that the product was composed of high-purity basic magnesium sulfate whiskers. The lengths and diameters of the whiskers were 10–20 μm and 0.1–0.2 μm, respectively, and their aspect ratios were higher than 30. The formation mechanism of 5Mg(OH)2·MgSO4·7H2O involved direct assembly from the precursors without the formation of magnesium hydroxide for redissolution. High-purity MgO whiskers with smooth surfaces were prepared using the as-prepared whisker products via thermal decomposition. Thus, the findings of this study can provide technical support for the cost-effective industrial-scale preparation of basic magnesium-sulfate whiskers and associated whisker products. [ABSTRACT FROM AUTHOR]

In this article, the capabilities of soft and hard X-ray techniques, including X-ray absorption (XAS), soft X-ray emission spectroscopy (XES), resonant inelastic soft X-ray scattering (RIXS), X-ray photoelectron spectroscopy (XPS), and X-ray diffraction (XRD), and their application to solid-state hydrogen storage materials are presented. These characterization tools are indispensable for interrogating hydrogen storage materials at the relevant length scales of fundamental interest, which range from the micron scale to nanometer dimensions. Since nanostructuring is now well established as an avenue to improve the thermodynamics and kinetics of hydrogen release and uptake, due to properties such as reduced mean free paths of transport and increased surface-to-volume ratio, it becomes of critical importance to explicitly identify structure-property relationships on the nanometer scale. X-ray diffraction and spectroscopy are effective tools for probing size-, shape-, and structure-dependent material properties at the nanoscale. This article also discusses the recent development of in-situ soft X-ray spectroscopy cells, which enable investigation of critical solid/liquid or solid/gas interfaces under more practical conditions. These unique tools are providing a window into the thermodynamics and kinetics of hydrogenation and dehydrogenation reactions and informing a quantitative understanding of the fundamental energetics of hydrogen storage processes at the microscopic level. In particular, in-situ soft X-ray spectroscopies can be utilized to probe the formation of intermediate species, byproducts, as well as the changes in morphology and effect of additives, which all can greatly affect the hydrogen storage capacity, kinetics, thermodynamics, and reversibility. A few examples using soft X-ray spectroscopies to study these materials are discussed to demonstrate how these powerful characterization tools could be helpful to further understand the hydrogen storage systems.

The carbon-based composite materials prepared through green synthetic approach are attracting greater interest in electrochemical applications due to their sustainable nature. Herein, we developed Fe 2 O 3 and Fe 2 O 3 @CNT composite materials via a green mechanochemical one-pot method. The as prepared composite materials were characterized by X-ray diffraction (XRD), energy dispersive X-Ray spectroscopy (EDS), field emission scanning microscopy (FE-SEM), high resolution transmission electron microscopy (HR-TEM), and X-ray photoelectron spectroscopy (XPS), respectively. Incorporating Fe 2 O 3 nanoparticles on CNT surface tunes its electronic structure as well increases active sites and thus enhance the oxygen evolution reaction (OER) performance. As a result, the fabricated Fe 2 O 3 @CNT is a highly effective and balanced electrocatalyst that delivers superior current density (j = 10 mA cm−2) at low overpotential (η = 270 mV) for OER compared with pristine Fe 2 O 3 (η = 290 mV) in 1 M KOH. Further, Fe 2 O 3 @CNT electrocatalyst shows high long-term durability in 1 M KOH for 100 h, fulfilling all the advantageous viable standards for OER. [ABSTRACT FROM AUTHOR]

Herein, a series of Fe–Ti bimetal oxide adsorbents were prepared by reduction–co-precipitation method, and their performance in removing low concentration H2S at room temperature was investigated. The adsorbents were characterized by X-Ray diffraction (XRD), Scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), Ultraviolet Visible diffuse reflectance spectroscopy (UV–Vis-DRS), X-Ray photoelectron spectroscopy (XPS) and N2 adsorption–desorption. The results showed that the addition of Ti increased the specific surface area, pore volume and small oligomeric Fe2O3 of ferrihydrite. When the Fe/Ti molar ratio was 8:1, Fe–Ti bimetal oxide formed a large amount of oligomeric Fe2O3, and its specific surface area and pore volume reached 344.99 m2/g and 0.34 cm3/g, respectively. At this time, Fe–Ti bimetal oxide exhibited the highest breakthrough sulfur capacity of 222.8 mg/g. High temperature calcination caused Fe–Ti bimetal oxide to form small specific surface area and pore volume, and produced crystalline α-Fe2O3. And the breakthrough sulfur capacity of Fe–Ti bimetal oxide decreased with the increasing calcination temperature. In addition, the desulfurization process conformed to the unreacted shrinking nucleus model. [ABSTRACT FROM AUTHOR]

Direct laser interference patterning (DLIP) is a versatile technique for surface patterning that enables formation of micro-nano sized periodic structures on top of the target material. In this study, DLIP in high pressure, supercritical and liquid CO2 by 4-beam DLIP was used to pattern titanium and zinc targets. Field emission scanning electron microscopy, atomic force microscopy, and X-ray photoelectron spectroscopy was used to characterize the patterned surfaces. Field emission SEM analysis showed presence of ordered uniform donut ring pattern with hollow centers for both titanium and zinc with a period slightly under 3 µm while topographical images from atomic force microscopy revealed donut rings protruding outwards typically around 200 nm from target surface and consisted of a crevice at the center with a depth typically around 300 nm and 250 nm for titanium and zinc target, respectively. Based on X-ray photoelectron spectroscopic analysis, this is the first study to report formation of TiO2, TiC, ZnCO3, and zinc hydroxy carbonate on the pattern by DLIP in supercritical and liquid CO2 for titanium and zinc targets. Pressurized CO2 is demonstrated as a promising environment with mirror-based DLIP system for reactive patterning. Due to the superior transport properties and solvent power of supercritical CO2, the current study opens possibilities for reactive patterning in environments that may not have been previously possible. [ABSTRACT FROM AUTHOR]

Direct laser interference patterning (DLIP) is a versatile technique for surface patterning that enables formation of micro-nano sized periodic structures on top of the target material. In this study, DLIP in high pressure, supercritical and liquid CO2 by 4-beam DLIP was used to pattern titanium and zinc targets. Field emission scanning electron microscopy, atomic force microscopy, and X-ray photoelectron spectroscopy was used to characterize the patterned surfaces. Field emission SEM analysis showed presence of ordered uniform donut ring pattern with hollow centers for both titanium and zinc with a period slightly under 3 µm while topographical images from atomic force microscopy revealed donut rings protruding outwards typically around 200 nm from target surface and consisted of a crevice at the center with a depth typically around 300 nm and 250 nm for titanium and zinc target, respectively. Based on X-ray photoelectron spectroscopic analysis, this is the first study to report formation of TiO2, TiC, ZnCO3, and zinc hydroxy carbonate on the pattern by DLIP in supercritical and liquid CO2 for titanium and zinc targets. Pressurized CO2 is demonstrated as a promising environment with mirror-based DLIP system for reactive patterning. Due to the superior transport properties and solvent power of supercritical CO2, the current study opens possibilities for reactive patterning in environments that may not have been previously possible. [ABSTRACT FROM AUTHOR]

Direct laser interference patterning (DLIP) is a versatile technique for surface patterning that enables formation of micro-nano sized periodic structures on top of the target material. In this study, DLIP in high pressure, supercritical and liquid CO2 by 4-beam DLIP was used to pattern titanium and zinc targets. Field emission scanning electron microscopy, atomic force microscopy, and X-ray photoelectron spectroscopy was used to characterize the patterned surfaces. Field emission SEM analysis showed presence of ordered uniform donut ring pattern with hollow centers for both titanium and zinc with a period slightly under 3 µm while topographical images from atomic force microscopy revealed donut rings protruding outwards typically around 200 nm from target surface and consisted of a crevice at the center with a depth typically around 300 nm and 250 nm for titanium and zinc target, respectively. Based on X-ray photoelectron spectroscopic analysis, this is the first study to report formation of TiO2, TiC, ZnCO3, and zinc hydroxy carbonate on the pattern by DLIP in supercritical and liquid CO2 for titanium and zinc targets. Pressurized CO2 is demonstrated as a promising environment with mirror-based DLIP system for reactive patterning. Due to the superior transport properties and solvent power of supercritical CO2, the current study opens possibilities for reactive patterning in environments that may not have been previously possible. [ABSTRACT FROM AUTHOR]

Direct laser interference patterning (DLIP) is a versatile technique for surface patterning that enables formation of micro-nano sized periodic structures on top of the target material. In this study, DLIP in high pressure, supercritical and liquid CO2 by 4-beam DLIP was used to pattern titanium and zinc targets. Field emission scanning electron microscopy, atomic force microscopy, and X-ray photoelectron spectroscopy was used to characterize the patterned surfaces. Field emission SEM analysis showed presence of ordered uniform donut ring pattern with hollow centers for both titanium and zinc with a period slightly under 3 µm while topographical images from atomic force microscopy revealed donut rings protruding outwards typically around 200 nm from target surface and consisted of a crevice at the center with a depth typically around 300 nm and 250 nm for titanium and zinc target, respectively. Based on X-ray photoelectron spectroscopic analysis, this is the first study to report formation of TiO2, TiC, ZnCO3, and zinc hydroxy carbonate on the pattern by DLIP in supercritical and liquid CO2 for titanium and zinc targets. Pressurized CO2 is demonstrated as a promising environment with mirror-based DLIP system for reactive patterning. Due to the superior transport properties and solvent power of supercritical CO2, the current study opens possibilities for reactive patterning in environments that may not have been previously possible. [ABSTRACT FROM AUTHOR]

The accumulation of toxic heavy metal ions continues to be a global concern due to their adverse effects on the health of human beings and animals. Adsorption technology has always been a preferred method for the removal of these pollutants from wastewater due to its cost-effectiveness and simplicity. Hence, the development of highly efficient adsorbents as a result of the advent of novel materials with interesting structural properties remains to be the ultimate objective to improve the adsorption efficiencies of this method. As such, advanced materials such as metal–organic frameworks (MOFs) that are highly porous crystalline materials have been explored as potential adsorbents for capturing metal ions. However, due to their diverse structures and tuneable surface functionalities, there is a need to find efficient characterization techniques to study their atomic arrangements for a better understanding of their adsorption capabilities on heavy metal ions. Moreover, the existence of various species of heavy metal ions and their ability to form complexes have triggered the need to qualitatively and quantitatively determine their concentrations in the environment. Hence, it is crucial to employ techniques that can provide insight into the structural arrangements in MOF composites as well as their possible interactions with heavy metal ions, to achieve high removal efficiency and adsorption capacities. Thus, this work provides an extensive review and discussion of various techniques such as X-ray diffraction, Brunauer–Emmett–Teller theory, scanning electron microscopy and transmission electron microscopy coupled with energy dispersive spectroscopy, and X-ray photoelectron spectroscopy employed for the characterization of MOF composites before and after their interaction with toxic metal ions. The review further looks into the analytical methods (i.e., inductively coupled plasma mass spectroscopy, ultraviolet-visible spectroscopy, and atomic absorption spectroscopy) used for the quantification of heavy metal ions present in wastewater treatment. [ABSTRACT FROM AUTHOR]

This article discusses the effect of silver oxide (Ag 2 O) on structural changes, apatite-forming ability, and bioactivity during addition onto the fluorophosphate glass (FPG) network. The foremost objective of silver incorporation on to fluorophosphate glass is to enhance the antibacterial efficacy of glass material which can be widely used as implants to minimize the post-surgical infections. Silver-added fluorophosphate glasses (AFPGs) with composition of 48P 2 O 5 –29CaO−(20− x)Na 2 O–3CaF 2 − x Ag 2 O (x = 0, 0.3, 0.6, 0.9, and 1.2 mol%) were prepared using conventional glass-melting method followed by rapid quenching technique. The in vitro apatite-forming ability of AFPG was evaluated by immersing the samples in simulated body fluid (SBF) for 21 days. The pH variations of the SBF solution were noted throughout the in vitro study and plotted to estimate dissolution mechanism. The structural properties and compositional estimation of AFPG samples before and after in vitro study were analyzed using X-ray diffractometer, Fourier transform infrared spectroscopy, scanning electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray photoelectron spectroscopy. Cytotoxicity of the prepared AFPG samples was evaluated using MTT assay. The bacteriostatic effect of AFPG samples were studied using different strains of bacteria such as Escherichia coli , Pseudomonas aeruginosa , Klebsiella pneumonia, Staphylococcus aureus , S. epidermidis, and S. mutans. The obtained peaks from XRD analysis at 28.12°, 31.73°, 46.71°, 29.11°, 32.25°, 51.59°, and 67.49° confirm crystalline nature and apatite formation on the glass surface. The attained characteristic FTIR peaks at 560 and 600 cm −1 shows the presence of apatite groups of vibration. The SEM image infers the spherical structure on the glass surface representing the presence of apatite layer and the EDAX graph shows the elemental composition of the prepared glass surface. From the present study, it was noted that glass sample containing 0.9 mol % of Ag 2 O enhanced apatite formation, was less cytotoxic and showed better antibacterial activity. Thus it can be inferred that AFPG0.9 sample can play a significant role in biomedical applications. [ABSTRACT FROM AUTHOR]

InN thin films are grown on sapphire substrates by remote plasma-assisted metal organic chemical vapor deposition while varying the indium pulse length and substrate temperature. The effects of the indium pulse length and temperature on the structural, morphological, electronic, and optical properties of the thin films are studied. The structural parameters are determined by X-ray diffraction and X-ray photoelectron spectroscopy and the effects of incorporating oxygen atoms in the structure is described. The N K-edge X-ray absorption spectroscopy (XAS) and X-ray emission spectroscopy (XES) measurements are used to determine the band gap and it is found to be 1.80 ± 0.25 eV for all samples. A complementary measurement namely, X-ray excited optical luminescence measurement is performed to confirm the band gap value obtained from XAS and XES measurements. O K-edge XAS measurements are performed to determine the presence of oxygen impurities in the samples. Meanwhile, we carry out the density functional theory calculations for Wurtzite InN, hypothetical Wurtzite-type InO0.5N0.5, and InO0.0625N0.9375 structures. We find that the measured N-edge spectra agree well with our Wurtzite InN calculations and the measured O K-edge spectra agree better with hypothetical Wurtzite-type InO0.0625N0.9375 than Wurtzite-type InO0.5N0.5. [ABSTRACT FROM AUTHOR]

The current investigation reports the influence of the addition of CdFeO nanoparticles on the structural and superconducting properties of the (Bi,Pb)-2212 phase. The formation of an orthorhombic phase of Bi-2212 superconductor is confirmed by the X-ray powder diffraction measurements. The scanning electron microscope measurements show an improvement in the grain connectivity and a decline of voids due to the CdFeO nanoparticles addition. The Fourier transform infra-red spectroscopy is used to associate the absorption bands to equivalent functional groups. The DC-electrical resistivity and the I-V characteristic measurements show an enhancement of the superconducting transition temperature (Tc) and the critical current density (Jc) up to 0.02 wt% addition of CdFeO, respectively. The elemental composition and oxidation states are determined using X-ray photoelectron emission spectroscopy. The results suggest a correlation between the electric behavior and the cationic equilibrium reactions among Pb2+ ions in Bi3+ or Cu2+ sites. [ABSTRACT FROM AUTHOR]

• Food waste can be converted into high-quality carbon quantum dots in under 5 min. • Carbon dots are produced at room temperature by NaCl cutting. • Environmental changes can be sensed using carbon dots. • Carbon dots are generated under low-energy consumption. In this study, we developed a low-energy-consumption green method for synthesising carbon dots (CD) at room temperature using watermelon rind as the carbon source through a cutting process based on NaCl crystals. The synthesis process was rapid (<5 min) and facile. The synthesised CD were characterised using photoluminescence (PL) spectroscopy, scanning electron microscopy, transmission electron microscopy, X-ray diffraction, Fourier-transform infrared spectroscopy, energy-dispersive X-ray analysis and X-ray photoelectron spectroscopy. The results revealed that the synthesised dots exhibited robust adsorption, a spherical shape and a uniform size distribution. The PL intensity of the quantum dots decrease due to the temperature rising, metal ions and ponceau 4R added. In contrast with PH, PL intensity increase, so these CD can serve as multifunctional sensing materials. Overall, this study presents an environmentally friendly method for the rapid synthesis of CD that are suitable for temperature, pH, metal ion and food sensing applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • NH 3 ·H 2 O–DMTD system has stronger activation effect on azurite than single DMTD. • NH 3 ·H 2 O–DMTD system mitigates azurite-flotation inhibition at high DMTD dosage. • The activity and stability of azurite surface product were markedly enhanced. • The colloidal content of Cu(I)-DMTD in the flotation solution was reduced. Azurite is an important alkaline copper carbonate mineral, and its efficient activation is important for improving the recovery of copper oxide minerals. 2,5-Dimercapto-1,3,4-thiadiazole (DMTD) is an excellent activator of azurite within a narrow dosage range but severely inhibits azurite flotation at high dosages. In practical industrial applications, precisely controlling the activator dosage is challenging. Herein, the effects of a new NH 3 ·H 2 O–DMTD activation system on the floatability and flotation interface characteristics of azurite were compared with those of a conventional single DMTD. The morphological evolutions, chemical compositions, and states of the azurite surface activation products were studied using X-ray photoelectron spectroscopy and field-emission scanning electron microscopy coupled with energy dispersive X-ray spectroscopy. The variation trends of the flotation solution components were determined using inductively coupled plasma–optical emission spectroscopy and ultraviolet–visible spectroscopy. Furthermore, the adsorption strength of a xanthate collector was characterized using time-of-flight secondary ion-mass spectrometry. Results show that the NH 3 ·H 2 O–DMTD system considerably strengthens the activation effect of DMTD on azurite, prevents flotation inhibition at high DMTD dosages, and effectively expands the optimal dosage range of DMTD. [ABSTRACT FROM AUTHOR]

[Display omitted] • The recovery of chrysocolla was significantly increased after co-modification with EDTA-2Na and CuSO 4. • The modified chrysocolla surface produced copper-containing components with enhanced active sites. • The modified chrysocolla promotes the adsorption of xanthate and enhances hydrophobicity. Chrysocolla is an important copper-oxide ore. However, because of the high surface hydrophilicity, and the small number of active sites, the effective flotation recovery of chrysocolla faces great challenges. In this study, ethylenediaminetetraacetic acid disodium (EDTA-2Na) and CuSO 4 were used as surface modifiers for chrysocolla, and the effects of surface modification on the flotation behavior, xanthate adsorption characteristics, and hydrophobicity of the chrysocolla were systematically investigated using micro-flotation, field-emission secondary electron microscopy with energy dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, X-ray diffraction, Fourier transform infrared spectroscopy, adsorption experiments, and contact angle measurements. Compared to direct flotation, the flotation recovery of chrysocolla after surface modification increased significantly from 25% to approximately 95%. During the modification process, neither EDTA-2Na nor SO 4 2- was effectively adsorbed onto the surface of the chrysocolla. CuSO 4 provided copper ions for to generate of stable copper-containing components on the surface of the chrysocolla, whereas EDTA-2Na acted as a modifier to promote the generation of copper-containing components on the surface of the chrysocolla. Surface modification increased the number and stability of copper-containing components on the chrysocolla surface. This promoted the effective adsorption of xanthate, improved the hydrophobicity of the mineral surface, and enhanced its flotation characteristics. [ABSTRACT FROM AUTHOR]

Fire accidents caused by coal spontaneous combustion seriously affect the production safety of coal mines. Carbon monoxide (CO) is an important gas indicator used for monitoring and early warning detection of coal spontaneous combustion. Therefore, the development of CO sensors with low cost, low power consumption, and environmental protection is highly desirable. This can be achieved through deep optimization of semiconductor CO sensors as alternatives to infrared detection and electrochemical sensors. In this paper, Ti3AlC2 (MXenes)/polyaniline (PANI) composite were studied as semiconductor CO sensors. The optimal added amount of Ti3AlC2 was determined by testing at gas concentrations of 100 ppm and 150 ppm CO. The morphology, structure, and chemical characteristics of each composite were analyzed by field emission transmission electron microscopy (SEM‐EDS), Fourier infrared spectrometry, UV‐visible near infrared spectrophotometer, X‐ray photoelectron spectroscopy (XPS), and thermogravimetric techniques. Compared to pure PANI material, the SEM‐EDS experimental results showed Ti3AlC2 with an increased number of PANI flake structures, generating more CO gas adsorption sites. The XPS results showed Ti3AlC2 was able of improving the protonation and oxidation degree of PANI, thereby improving its gas sensing performance. Accordingly, a sensing mechanism model was proposed, revealing the excellent sensing performance originating from the gas sensing enhancement effect of heterojunction. In sum, this study provided a scientific basis for the design and development of CO sensors with low cost, low power consumption, and future environmental protection. [ABSTRACT FROM AUTHOR]

Dopamine is a neurotransmitter that helps cells to transmit pulsed chemicals. Therefore, dopamine detection is crucial from the viewpoint of human health. Dopamine determination is typically achieved via chromatography, fluorescence, electrochemiluminescence, colorimetry, and enzyme-linked methods. However, most of these methods employ specific biological enzymes or involve complex detection processes. Therefore, non-enzymatic electrochemical sensors are attracting attention owing to their high sensitivity, speed, and simplicity. In this study, a simple one-step fabrication of a Bi2Te3-nanosheet/reduced-graphene-oxide (BT/rGO) nanocomposite was achieved using a hydrothermal method to modify electrodes for electrochemical dopamine detection. The combination of the BT nanosheets with the rGO surface was investigated by X-ray diffraction, X-ray photoelectron spectroscopy, field-emission scanning electron microscopy, transmission electron microscopy, Raman spectroscopy, and Fourier-transform infrared spectroscopy. Electrochemical impedance spectroscopy, cyclic voltammetry, and differential pulse voltammetry were performed to analyze the electrochemical-dopamine-detection characteristics of the BT/rGO nanocomposite. The BT/rGO-modified electrode exhibited higher catalytic activity for electrocatalytic oxidation of 100 µM dopamine (94.91 µA, 0.24 V) than that of the BT-modified (4.55 µA, 0.26 V), rGO-modified (13.24 µA, 0.23 V), and bare glassy carbon electrode (2.86 µA, 0.35 V); this was attributed to the synergistic effect of the electron transfer promoted by the highly conductive rGO and the large specific surface area/high charge-carrier mobility of the two-dimensional BT nanosheets. The BT/rGO-modified electrode showed a detection limit of 0.06 µM for dopamine in a linear range of 10–1000 µM. Additionally, it exhibited satisfactory reproducibility, stability, selectivity, and acceptable recovery in real samples. [ABSTRACT FROM AUTHOR]

Summary: Manganese‐based oxides are being actively studied as cathode materials for rechargeable aqueous zinc ion batteries (AZIBs) because of their high capacity, cost‐effectiveness, safety, and eco‐friendliness. Herein, we propose a binder‐free electrode of bivalent manganese oxide with the chemical composition of Mn5O8 deposited on stainless steel as a cathode of AZIBs. Mn5O8 nanoparticles with a layered structure, which provide a facile pathway for Zn2+ ion transport and diffusion, were directly deposited on a three‐dimensional stainless steel mesh via a hydrothermal method using different temperatures. The structures of the active materials in the cathode were characterized by X‐ray diffraction, high‐resolution transmission electron microscopy, X‐ray photoelectron spectroscopy, and field‐emission scanning electron microscopy. The Mn5O8 cathode materials exhibited a high specific capacity of 254.98 mAh g−1, and simultaneously demonstrated satisfactory reversible charge/discharge and high rate performance. The Zn2+ insertion/extraction behaviors were studied in detail by cyclic voltammetry. In addition, factors that influence the electrochemical performance of the cathode, such as the phase structure and particle size of manganese dioxide, are discussed. Smaller and homogeneous Mn5O8 particles provide a large interface area and facilitate more zinc ions for diffusion, leading to improved ionic current and specific capacity. [ABSTRACT FROM AUTHOR]

In this paper, the role of antimony (Sb) as a dopant in single-phase bulk Cu2ZnSnSe4 (CZTSe) has been studied. The sb-doped CZTSe bulk material has been synthesized via facile mechanical dry ball milling method. The structural characterization and phase formation were studied through X-ray diffraction (XRD) and Raman spectroscopy. Particle size and electron diffraction measurements were done using high resolution transmission electron microscopy and selected area electron diffraction. Field emission scanning electron microscope and energy dispersive X-ray spectroscopy analyses have been done to infer morphology and composition. Oxidation state of constituent elements in milled powder was studied by X-ray photoelectron spectroscopy analysis. The results of XRD and Raman results are suggestive that the dry milling is a reliable method for the synthesis of single-phase CZTSe. It is also possible to achieve doping with low concentrations of Sb during the milling process to obtain sb-doped bulk single-phase CZTSe. [ABSTRACT FROM AUTHOR]

TiO2 is a promising photocatalyst, but its large bandgap restricts its light absorption to the ultraviolet region. The addition of noble metals can reduce the bandgap and electron-hole recombination; therefore, we prepared TiO2-Ag nanoparticle composite films by plasma-enhanced chemical vapor deposition (PECVD) using a mixture of aerosolized AgNO3, which was used as a Ag nanoparticle precursor, and titanium tetraisopropoxide, which acted as the TiO2 precursor. Notably, the use of PECVD enabled a low process temperature and eliminated the need for pre-preparing the Ag nanoparticles, thereby increasing the process efficiency. The structures and morphologies of the deposited films were characterized by ultraviolet (UV)—visible spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, transmission electron microscopy and energy-dispersive X-ray spectroscopy, and the effects of the AgNO3 concentration on the photocatalytic activity of the deposited films were determined by assessing the degradation of methylene blue under UV light irradiation. The Ag ions were successfully reduced to metallic nanoparticles and were embedded in the TiO2 film. The best photocatalytic activity was achieved for a 1 wt% Ag-loaded TiO2 composite film, which was 1.75 times that of pristine TiO2. [ABSTRACT FROM AUTHOR]

Indium–tin oxide (ITO) thin films with reduced to 50 mass.% indium oxide content are grown by direct current (DC) sputtering of ITO target in mixed argon–oxygen atmosphere onto glass substrates preheated at 523 K. The films showing the best electrical properties are subsequently heattreated in air at temperatures of 523 and 623 K for 60 min. X-ray photoelectron spectroscopy (XPS) and x-ray emission spectroscopy (XES) are used for samples’ characterization. Effects of oxygen-flow rate, Sn content, and heat-treatment temperature on electronic properties are studied and discussed. XPS measurements show that indium is in In3 charge state, and tin is only in Sn4+ state in indium-saving ITO thin films sputtered at different conditions and heat-treated at different temperatures. As-deposited indium-saving ITO thin film sputtered at 0.5 cm3 STP/min oxygen-flow rate, which demonstrates the highest conductivity among the as-deposited thin films, shows the highest relative intensity of OII peak. The electron density of states increases when going from indium-saving thin film to typical ITO one. [ABSTRACT FROM AUTHOR]