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Lead tin sulphide (Pb-Sn-S) thin films (TFs) were deposited on fluorine-doped tin oxide (FTO) substrates via the electrochemical deposition process using lead (II) nitrate [Pb(NO3)2], tin (II) chloride dehydrate [SnCl2.2H2O] and thiacetamide [C2H5NS] precursors as sources of lead (Pb), tin (Sn) and sulphur (S). The solution of all the compounds was harmonized with a stirrer (magnetic) at 300k. In this study, we reported on the improvements in the properties (structural and optical) of Pb-Sn-S TFs by varying the deposition time. We observed from X-ray diffractometer (XRD) that the prepared material is polycrystalline in nature. UV-Vis measurements were done for the optical characterizations and the band gap values were seen to be increasing from 1.52 to 1.54 eV with deposition time. In addition to this, the absorption coefficient and refractive index were also estimated and discussed.

Utilising molecular dynamics simulation, the effect of segregation thickness and solute concentration on the mechanical properties of poly‐crystalline Ag‐doped Cu alloy are explored. The alloying atoms are dispersed randomly nearby grain boundaries with equidistant offset method. The dispersed domains are restricted in grain boundary affect zone. The uniaxial tensile simulation results indicate that dispersed alloying atoms exert a negative effect on the tensile behaviours of Ag‐doped Cu alloy and its peak stress decreases as the increasing of segregation thickness and solute concentration. Moreover, the corresponding tensile deformation mechanisms are analysed according to the observed dislocation activities and structure evolutions.

This study highlights the photovoltaic and electron transport properties of TiO2-SiO2-nickel-graphene oxide (GO) composite thin films annealed at various annealing temperatures. (SiO2)100-x-Nix (x = 7.5 wt.%) was synthesized using sol–gel method. The TiO2-(SiO2)-Ni-GO composite photoanodes were fabricated using doctor-blade technique for the usage of dye-sensitized solar cells (DSSCs). The objective of this research is to enhance the photovoltaic conversion efficiency of TiO2-SiO2-nickel-GO thin films by finding the optimum annealing temperature. Gel polymer from PAN-based is used as the electrolyte in this research. The crystalline structure, morphology, and the chemical properties of the thin films with various annealing temperatures will be reported. X-ray diffraction, field-emission scanning electron microscopy, and mapping analyses revealed that the synthesized nanoparticles had uniform nanometer grains with different phase composition and the crystallite sizes increase with annealing temperature from 30.14 to 42.43 nm. Energy dispersion X-ray and Fourier transform infrared spectroscopy also identified the elements and bonding that are associated with TiO2, SiO2, and other additional dopants. The performances of the photovoltaic were analyzed using J–V measurement and electrochemical impedance spectroscopy. The annealing treatment was able to modify the surface morphology whereby necks were developed on the surface due to high surface diffusions. The fine nanoparticles of thin films annealed at 350 °C showed more porosity with a high effective electron chemical diffusion coefficient that helped to improve the short-circuit current density in DSSC. The annealing treatment shows that the sheet resistance (Rs) increases with the increase in annealing temperature. It was also observed that the particle grains increased in numbers with the annealing temperature. It can be concluded that the photoanode annealed at 350 °C exhibited better photovoltaic performance at the highest power conversion efficiency of 3.40% due to having more porous structure, low recombination effect, and a large diffusion rate.

Due to its high hardness, chemical and thermal resistance, TiB2 has become a great candidate to be used as a protective coating. However, high residual stresses after the deposition and brittleness have become the main obstacles for implementation at industrial levels. In the present work, the incorporation of graphite was studied as an alternative to improve the performance of the TiB2 coatings and study the influence in the microstructure, Nano mechanical and tribological properties. Ti–B–C coatings were deposited with different carbon contents of 10, 20, 28 and 38 at%. XRD results showed that the carbon atoms enter within the crystal lattice of the TiB2 forming a solid solution, and consequently, deforming crystal and modifying its lattice parameter of 3.2237–3.3414 A. HRTEM images and selected area electron diffraction patterns analysis display the low crystallite or degree of amorphosity due to the carbon concentration (C1.9 mol). Compressive residual stresses decrease in the coatings containing the higher amounts of carbon. The formation of a TiB2-C solid solution contributed to the increment of nanohardness (H = 25 GPa) and improvement of the resistance to plastic deformation (H3/E2) of coatings. Regarding the tribological behaviour of the coatings, higher friction coefficient than those obtained on the uncoated substrate were observed. However, a reduction of the wear rate was also evident. The presence of a high amount of debris and severe wear of the counterpart material indicates a highly aggressive tribological contact. Roll-like debris with a shape of needles was found within the tribological tracks perpendicular to the sliding direction.

This research work reports the novel synthesis of tungsten trioxide (WO3) and chromium (Cr) doped titanium dioxide (TiO2) for photocatalytic and shelf-life applications through the sol–gel method. The optimal incorporation of WO3 and Cr into TiO2 nano-spheres results in the enhancement of photocatalytic properties as well as shelf-life of apples. The crystallinity, morphology, purity, elemental composition, optical properties, presence of functional groups and bandgap of the prepared samples were analyzed by XRD, SEM, EDX, FTIR, PL and UV–Vis absorption spectroscopy respectively. The XRD results revealed that the average crystallite size is 24 nm having well-distinguished peaks. SEM micrographs showed that pure TiO2 has a nanosphere structure but doping significantly changed the morphology into nanoflowers. The average particle size is between 10 and 100 nm but due to agglomeration of the particles, some particles have size greater than 100 nm as well. The UV–Vis spectroscopy successfully confirmed the decrease of bandgap from 3.2 to 2.5 eV. The degradation of Rhodamine-B (RHB) dye as a model organic pollutant over 180 min was used to examine the photocatalytic performance of fabricated samples. This Work reveals that 3% WO3/TiO2 has a maximum degradation efficiency of 94 percent. This sample was also found to be photostable, anti-photo corrosive, environmentally friendly, and reusable after several cycles of activity. The use of WO3/TiO2 resulted in the greatest increase in apple’s shelf life. These findings indicate that the 3% WO3/TiO2 can be used as a photocatalyst for organic pollutant degradation and a best catalyst to enhance the shelf-life of apples. This fact confirms the co-relation of photocatalysis and shelf-life applications.

Reactive transport modeling (RTM) is an essential tool for the prediction of contaminants' behavior in the bio- and geosphere. However, RTM of sorption reactions is constrained by the reactive surface site assessment. The reactive site density variability of the crystal surface nanotopography provides an "energetic landscape", responsible for heterogeneous sorption efficiency, not covered in current RTM approaches. Here, we study the spatially heterogeneous sorption behavior of Eu(III), as an analogue to trivalent actinides, on a polycrystalline nanotopographic calcite surface and quantify the sorption efficiency as a function of surface nanoroughness. Based on experimental data from micro-focus time-resolved laser-induced luminescence spectroscopy (μTRLFS), vertical scanning interferometry, and electron back-scattering diffraction (EBSD), we parameterize a surface complexation model (SCM) using surface nanotopography data. The validation of the quantitatively predicted spatial sorption heterogeneity suggests that retention reactions can be considerably influenced by nanotopographic surface features. Our study presents a way to implement heterogeneous surface reactivity into a SCM for enhanced prediction of radionuclide retention.

The present work describes comparative study of annealing temperature in the range of 500–900 °C on the successful synthesis of Gd/Mn2SnO4 nanocomposite via sol gel method followed by hydrothermal method. Structural, optical, photoluminescence, photocatalytic activities against methylene blue and methyl orange; and antifungal features against Aspergillus niger of Gd/Mn2SnO4 nanocomposite were studied. The structural and optical properties were investigated using X-ray diffraction (XRD), thermogravimetric analysis (TGA), fourier transform infrared spectroscopy (FTIR), UV–Visible spectroscopy and particle size analyzer (PSA) techniques. Crystallite size, particle size and optical band gap were calculated using XRD, PSA and Uv–visible spectroscopy, respectively. Gd/Mn2SnO4 nanocomposite annealed at 500 °C is found to be a competent photo catalyst for degradation of dyes used for the study and for the growth inhibition of Aspergillus niger.

Undoped and Y-doped CuSe with different dopant concentration (0.01–0.04 mol%) have been successfully synthesized using selenium (IV) oxide (SeO2), copper (II) sulfate pentahydrate (CuSO4⋅5H2O), and yttrium as sources of Cu2+, Se2−, and Y3+ ions, respectively, on glass slides via spray pyrolysis method. The impact of yttrium doping on the structural, compositional, morphological, electrical, and optical properties of CuSe were studied using X-ray diffractormeter, Scanning electron microscopy-SEM, Energy dispersive X-ray spectroscopy-EDX, four-point probe, and 756S UV–Visible spectrophotometer accordingly. The XRD result reveals that the deposited thin materials exhibited a polycrystalline cubic structure with preferred orientation along (200), while the EDX result affirms the existence of the fundamental elements deposited. The electrical studies result supported the fact that the thin films are semiconductors. The optical results revealed high absorbance, low transmittance, and narrowed energy band gap of CuSe films after adding yttrium dopant. Undoped CuSe recorded an energy band gap value of 3.0 eV which experienced a declined range from 2.81 to 2.50 eV upon Y doping. Addition of Y dopant was seen to improve the crystallinity of the films and narrowed the energy band gap of undoped CuSe, thereby boosting the performance of YCuSe for use as photovoltaic material and also a more reliable material for absorber layer in solar energy collection.

The article presents a microstructure-based mechanical model of hexagonal close-packed (hcp) a-titanium representative of the mesoscale and analyzes the contribution of a pyramidal slip to plastic deformation. We discuss the size of a representative volume element (RVE) enabling mesoscale phenomena to be correctly reproduced, focusing on deformation-induced surface roughening (DISR) and plastic strain localization. It is shown that the ignorance of a pyramidal slip in simulations leads to overestimated stress values in an hcp material. A polycrystalline model is capable of reproducing the mesoscale phenomena until plastic strain begins to localize at the length scale comparable to the model size

In the present research work, Mg-doped zinc oxide Zn0.1−xMgxO (For x = 0.000, 0.002, 0.006, 0.010) nanoparticles were synthesized by co-precipitation method. The effect of Mg2+ ions substitution on structural, phase transformation, morphological, and optical properties was investigated using X-ray diffraction (XRD), Raman spectroscopy, Field emission scanning electron microscopy (FE-SEM), and UV–Visible spectroscopy (UV–Vis), respectively. The XRD study shows the formation of pure hexagonal wurtzite phase which was also confirmed using Rietveld refinement performed using Fullprof software. The average crystallite size of Mg-doped zinc oxide nanoparticles calculated using Debye–Scherrer relation found to vary from 43.36 to 36.12 nm with increase in Mg concentration from 0 to 10%. The UV–Vis study reveals the blue shift in optical band gap for all the samples as molar concentration of Mg increases in ZnO lattice which was attributed to quantum confinement effect. Further, results of other studies including XRD viz., Raman, UV–Vis, and FE-SEM show that this method of synthesis can be utilized for increasing the optical band gap of the Zn0.1−xMgxO nanocrystals by retaining the pure ZnO phase up to 10% doping of Mg2+ ions concentration.

In this present work, the pristine and the different percentages of co-doped NiO nanoparticles have been successfully synthesized through the sol–gel method. The X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), UV–Visible spectroscopy (UV-Vis), Fourier Transform Infra-Red Spectroscopy (FT-IR), and Vibrating Sample Magnetometer (VSM) were used to study the structural, morphological, optical, functional, and magnetic properties of the synthesized materials. The XRD patterns confirmed the formation of cubic phased NiO with their crystallite size, microstrain, dislocation density was estimated, and the average crystallite size increased with co-dopant inclusion. By introducing the co-dopant proportion in NiO lattice, the intensity of optical absorption was found to increase and the optical bandgap decreased from (Eg = 3.6, 3.54, 3.50 eV) due to quantum size effect. SEM result exhibits that the particles are spherical-shaped morphology. The VSM examination shows the magnetic transition of soft to hard-ferromagnetism in room temperature on Zn, Mn co-dopant ions occupying Ni translational symmetry.

The development of original nanoparticle size and shape requires a detailed knowledge and rationalization of the formation mechanism. A consolidated mechanism of γ-AlOOH boehmite nanorod formation ...

The effect of Cu addition on crystal structure, compressive properties and shape-memory effect of Ni50Mn25Ga25−x Cu x alloys was studied. With increasing Cu content, the type of crystal structure evolves following a sequence: L21 → 10M → 2M → 2M+γ. Addition of Cu significantly improves room temperature ductility. In polycrystalline Ni50Mn25Ga17Cu8 alloy, a full recoverable strain equal to 7 pct was achieved. High martensitic transformation temperature and large shape-memory effect makes this material potential candidate in high-temperature shape-memory applications.

Bismuth thiophosphate, BiPS4, is a promising nontoxic, high-density ternary chalcogenide semiconductor. Polycrystalline BiPS4 was synthesized from the stoichiometric melt of Bi, P, and S. Phosphoru...

Textile dyeing wastewater becomes one of the root causes of environmental pollution. Titanium dioxide (TiO2) is one of the photocatalysts that shows prominent organic dye photodegradation ability. In this study, a porous tungsten oxide (WO3)/TiO2 composite was prepared through ultrasonic-assisted solvothermal technique with varying amounts of WO3 ranging from 0.25 to 5 weight % (wt.%). The prepared 0.50 wt.% WO3/TiO2 (0.50WTi) composite exhibited the highest photodegradation activity (4.39 × 10−2 min−1) and complete mineralization in chemical oxygen demand (COD) reading towards 30 mg.L−1 of Reactive Black 5 (RB5) dye under 60 min of light irradiation. Effects of large surface area, small crystallite size, high pore volume and size, and low electron-hole pair recombination rate attributed to the superiority of 0.50WTi. Besides, 0.50WTi could be reused, showing 86.50% of RB5 photodegradation at the fifth cycle. Scavenger study demonstrated that photogenerated hole (h+) was the main active species of 0.50WTi to initiate the RB5 photodegradation. Cytotoxicity assessment determined the readings of half-maximal inhibitory concentration (IC50) were 1 mg.mL−1 and 0.61 mg.mL−1 (24 and 72 h of incubations) for the 0.50WTi composite.

The magnetocrystalline anisotropy and the exchange bias in nanocrystalline FeCo with and without a post-synthesis high-temperature thermal treatment have been investigated. The synthesized products were characterized using X-ray diffraction (XRD), field-emission scanning electron microscopy (FE-SEM), energy dispersive X-ray spectroscopy (EDS) and dc magnetization. The XRD spectra revealed the presence of secondary phases which reduced after thermal treatment resulting in the formation of single-phase polycrystalline FeCo. The FE-SEM micrographs confirmed the formation of impurities, which disappeared after thermal treatment, along with the substantial grain growth. The uniform distribution of the elements was confirmed through EDS spectra. The temperature and the magnetic field-dependent magnetization measurements under various conditions showed that, as a consequence of thermal treatment, the saturation magnetization and the magnetocrystalline anisotropy has been enhanced along with the generation of exchange bias. The phenomena of grain growth, formation of grain boundary and the exchange interactions have been described with the help of the proposed mechanism. In brief, the post-synthesis high-temperature thermal treatment induced structural as well as microstructural variations leading to the formation of grain boundaries. These grain boundaries provided interface regions for the occurrence of exchange interactions, which enhanced the magnetocrystalline anisotropy and induced exchange bias in nanocrystalline FeCo.

The present study reports on the synthesis of Fe-doped tungsten trioxide (WO3:Fe) thin films using spray-pyrolysis technique. The films were deposited on glass substrates at 350°C and Fe-doping was achieved using granular iron in an acidic medium with $$\frac{{\left[ {{\text{Fe}}} \right]}}{\left[ W \right]}$$ = 1, 3 and 5 % at. The films were heat-treated with an extended thermal treatment at 400°C and 500°C for 4 h, in order to allow both crystallization and dopant diffusion into the WO3 matrix. The effect of Fe-doping and heat-treatment on the morphological, structural and optical properties of these films was investigated. The results revealed that Fe-doping has a significant impact on the morphology of the films depending on its concentration. In addition, it was shown that the thermal treatment improves the growth of the crystallites and enhances the roughness of the surface. Grazing incidence X-ray diffraction analysis (GIXRD) confirmed the polycrystalline character of the films with a monoclinic structure (ICDD N° 89-4476, P21/c). The structural parameters were found to be both doping- and heat-treatment-dependent. Energy dispersive spectrometry (EDS) depicted homogeneous doping and confirmed the presence of W, O and Fe. The films display a good optical transmittance over the visible region sensitive to Fe-doping and thermal treatment. Moreover, the films exhibit both direct and indirect electronic transitions, where the energy of the indirect electronic allowed transition shows a redshift in all the samples due to Fe-doping. Therefore, the width of the tail states energy increases inferring the influence of disorder and the introduction of defect states within the band gap region.

Pure and sodium-containing lanthanum oxymolybdates were synthesized as polycrystalline samples and single crystals. The compounds have been characterized by several methods including SEM, inductive...

Cost-effective and controllable synthesis of M0.25Ni0.15Cu0.25Co0.35Fe2O4 (M2+ = Mg2+, Mn2+, and Cd2+) ferrites via the sol–gel auto-combustion technique. The impact of divalent cations on the structural, dielectric, and optoelectrical properties of ferrites was examined by XRD, FTIR, Raman, LCR, UV–Vis, and two probe I-V measurement techniques. The crystallite size was 52.66 nm, and the minimum specific surface area was observed 5.1507 m2/g for Mg2+ doped NCCF ferrite. The FTIR and Raman analysis also confirmed the substitution of divalent cations (M2+ = Mg2+, Mn2+, and Cd2+) at their respective lattice sites. The maximum energy bandgap was 1.67 eV Mg2+-doped NCCF ferrite as compared to other divalent ion-doped ferrites. The dielectric loss decreased while the ac conductivity increased with increasing frequency, and the minimum values were observed for Mg2+-doped NCCF ferrite. The activation energy was observed maximum for Mg2+-doped NCCF ferrite (0.2234 eV). Due to incredible properties including small specific surface area, large energy band gap, high resistivity, and loss dielectric loss of Mg2+-doped NCCF ferrite have potential applications in different fields.

The influence of indium on the properties of Cu0.5Zn0.5Fe2O4 nano ferrites synthesized by sol–gel auto-combustion technique was studied. X-ray diffraction (XRD) analysis demonstrated that pure and substituted ferrites possessed cubic spinel structure. The lattice parameter increases with the inclusion of In3+ for x ≤ 0.16 and decreases subsequently. A linear decrease in crystallite size was found as concentration of indium increased. X-ray density, strain, and dislocation density were increased as indium content increases. Hopping lengths as well as radii of A and B sites revealed increasing behavior up to x = 0.16 and decreased thereafter. The spectral bands indicated the formation of spinel structure. The band positions were altered with the increase of In3+ contents. The inclusion of indium ions increases the value of dielectric parameters while magnetic parameters decreased. This increase in dielectric parameters and decrease in magnetization proposed that synthesized magnetic oxides may have potential in the fabrication of switching and high-frequency devices.

In the present study, we reports the fabrication of n-ZnO/p-Si++ hetero-junction devices for the detection of hydrogen leakage in ambient air environment. For the fabrication of n-ZnO/p-Si++ hetero-junction devices, high quality ZnO thin films are grown by controlled thermal evaporation technique on the highly doped p-type silicon substrates at 400 oC. The two sets of films deposited at 400 o C are further annealed at 500 and 600 oC to examine the effect of annealing temperature on the structural, morphology, electrical and gas sensing properties of the deposited films. It is revealed from the x-ray diffraction studies that the crystallite size, and the density of the films increase from 22.55 to 24.95 nm, from 5.65 to 5.68 g/cm3, respectively, on increasing the fabrication temperature from 400 to 600 oC. In contrast to it, the grain boundary specific surface area decrease from 8.79 x107 to 7.88 x107 m-1 on changing the fabrication temperature from 400 to 600 oC. The hydrogen gas sensing response of the fabricated devices has also been recorded at different operating temperatures and different hydrogen concentrations (200 to 1000ppm) in air ambient. It is found that the gas sensing response of the fabricated devices increase with increase in operating temperature (up to 100 oC) and decease beyond this temperature. The gas sensing responses of the devices fabricated at 400, 500 and 600 oC are found to be 97.22, 64.23 and 40.77 % at 1000 ppm of hydrogen. A decrease in gas sensing response with fabrication temperature is attributed to the increase in crystallite size (quantum size effect), density of films (i.e. lower penetration) and decrease in grain boundary specific surface area (i.e. active sites) with annealing temperature. The mechanism of the gas sensing in these devices has also been systematically analyzed under different models.

The rare earth element praseodymium (Pr)-substituted Li/Ni ferrite nanomaterial, Li0.5Ni0.5PrxFe2−xO4 (x = 0, 0.01, 0.02, 0.03) has been prepared using cost-effective citrate precursor method. The ferrite magnetic materials are iron-oxide-based materials and at nanometric scale very promising for its multifunctional applications in electronics industries, purification of water and as nanomedicine. In this present research, structural, surface morphology, optical, electronic, and magnetic properties together with cytotoxicity and lymphoproliferation on murine spleen cells have been studied. The X-ray diffraction measurement reveals the formation of pure cubic spinel structure having space group Fd3m. The lattice parameter shows a slight decrement. Furthermore, crystallite size and lattice strain were calculated using W–H plot and show the decrement from 37 to 21 nm with substitution of praseodymium ion. Surface morphology and nanometric scale particle size measurements were carried away using SEM and HRTEM analysis for lattice plane and d-spacing. The bond length was found to increase, while the force constant was found to decrease by the increment of Pr atom. The indirect band gap energies were improved with the substitution of rare-earth ion. The saturation magnetization value was found between 33.5 and 6.73 emu/g for Li0.5Ni0.5PrxFe2−xO4ferrites. The coercivity was estimated in between 185.24 and 98.78Oe for Li–Ni-nanoferrite system. In addition, the observed in vitro cytotoxicity and lymphoproliferative results appeared to be biocompatible and concentrations dependent, as studied by MTT and BrdU assays. The present research results indicate that rare earth element Pr-substituted ferrite magnetic nanomaterial may be applied in transformer cores because of reduced coercivity in opto-electronic instruments owing to improved optical properties and as iron-oxide-based nanomaterials for its uses in health and medical science sector.

In order to seek potential buffer layer, the influence of different vacuum annealing levels on physical properties to e-beam evaporated Zinc Selenide (ZnSe) thin films are meticulously investigated herein. The X-ray diffraction patterns of vacuum-annealed ZnSe films confirmed the prominent (111) reflection of the cubic phase where the crystallite size is found maximum (29 nm). The wavy optical transmittance spectra are observed for these ZnSe films, where higher transparency is observed in the visible region. A blue shift in the optical band gap (2.56–2.81 eV) and shrink in refractive index from 2.49 to 2.40 is observed with increasing vacuum levels. The HRTEM images demonstrated (111), (220), and (311) orientations of the lattice planes, and EDS patterns confirmed deposition of ZnSe films. The ohmic nature of the analyzed ZnSe thin films is validated by the I–V characteristics where the resistivity is found in the order of 102 Ω-cm for vacuum-annealed and 104 Ω-cm for the pristine films. The AFM images indicated hill-like structures where the roughness is found to vary with vacuum level. The physical properties of ZnSe films are conspicuously tailored by vacuum annealing levels, and the findings recommend the use of ~ 5 × 10−3 mbar vacuum-annealed ZnSe thin films as potential buffer layer to the solar cells.

Polycrystalline spinel nickel ferrite nanoparticles were prepared by employing sol–gel auto combustion method. The as-prepared nanoparticles were characterized using XRD and FTIR for structural characterization, the morphology of the samples was analyzed from the FESEM micrographs. The XRD analysis validated the cubic spinel structure of the synthesized NiFe2O4 nanoparticles. The octahedral and tetrahedral locations of metal oxide bands were proven by two prominent metal oxide bands in the FTIR spectrum at 466 and 589 cm−1, respectively. The prepared nanoparticles are in spherical morphology, according to the FESEM analysis. The optical properties exhibited by the NiFe2O4 nanoparticles was examined by studying UV–Vis spectroscopy and photoluminescence spectra. The magnetic properties were studied at room temperature by employing VSM analysis. Agar well diffusion tests procedures were used to assess the bactericidal effect of nickel ferrite particles. Using Dalton’s Lymphoma Ascites cells, the nickel ferrite nanoparticles were investigated for short-term in vitro cytotoxicity. The presence of NiFe2O4 inhibits Bacillus subtilis and Klebsiella pneumonia growth.

Effect of 1 wt% TiO2@carbon nanotubes (TiO2@CNTs) and 1 wt% praseodymium (Pr) on the microhardness and corrosion properties of AZ91 magnesium alloy were discussed. The microhardness test, electrochemistry test that AZ91 magnesium alloy with 1 wt% TiO2@CNTs and 1 wt% Pr addition exhibits excellent microhardness (111 HV), low corrosion current density (0.165 mA·cm−2), and low polarization resistance (537.15 Ω·cm2) compared with AZ91 magnesium alloy (89 HV, 0.184 mA·cm−2, 261.06 Ω·cm2). After 1 wt% TiO2@CNTs and 1 wt% Pr added to AZ91, the average crystallite size was reduced and microhardness was increased. Additionally, the Al11Pr3 phase formed by the combination of Pr and Al transformed the morphology of β-Mg17Al12 phase into weeny particles and decreased the volume fraction of β-Mg17Al12 phase. The reduction and refinement of cathode phase (β-Mg17Al12 phase) weakened the micro-galvanic corrosion and slowed down the corrosion rate.

In this report, we studied the optical and dielectric properties of lanthanum doped lead sulphide (La@PbS) nanoparticles prepared by microwave assisted synthesis method. Crystallite phase of the prepared samples was confirmed through X-ray diffraction analysis. The uniformity and homogeneity of La@PbS was recorded by SEM analysis. The particles size were found to increase with La content. The band gap values vary between 0.87 and 1.00 eV and influenced by the La concentration. Dielectric constants are highly dependent on both the applied frequency and La doping, whose values ranges between 23 and 41. The AC conductivity studies show that, they follow Jonscher’s power law relationship, and their DC electrical resistivity decreases with La concentration. The outcomes suggested that the optoelectronics properties of prepared PbS samples can be widely tuned with La doping.

This paper reports a detail crystallographic investigation of a well-known biphasic biomaterial containing hydroxyapatite (HAp) and β-tricalcium phosphate (β-TCP). This biphasic calcium phosphate bioceramic (BCP) was synthesized by three typical methods: (i) solid-state method (where CaCO3 and (NH4)2HPO4 was the source of Ca and P, respectively); (ii) wet chemical method (where the reactants were Ca(OH)2 and H3PO4); and (iii) direct incineration of bovine bones. Furthermore, the adopted fourth method to synthesize the biphasic biomaterial was UV irradiation instead of high temperature calcination. In each case the synthetic biphasic biomaterial was characterized by employing X-ray diffraction (XRD) and Fourier transform infrared (FT-IR) techniques. Various crystallographic parameters such as crystallite size, dislocation density, microstrain, crystallinity index (from XRD and FT-IR), HAp percentage, β-TCP percentage, the volume fraction of β-TCP, and degree of crystallinity were estimated by conventional approaches for the broader applicability of this biphasic biomaterial. Two new models for measuring microstrain and one new method (XRD-sin2Ѱ technique) for calculating residual stress (also known as intrinsic stress) were developed to estimate the crystallographic parameter more accurately. A linear relationship was illustrated among the value of conventional methods and newly developed techniques without significant difference (R2 = more than 0.9) among the values of four types of HAp.

Pyrolysis of buckwheat straw with or without catalysts was investigated using the TGA-FTIR method to determine the influence of nickel and cobalt ferrites on the distribution of pyrolysis products. According to the obtained results, the overall shape of the thermogravimetric and derivative thermogravimetric curves is unchanged in the presence of nickel and cobalt ferrites but different weight losses were observed. All catalysts contribute to the formation of solid residue from BWS pyrolysis. The presence of cobalt ferrites exhibited the highest bio-oil yields, whereas the highest non-condensable gas yield and the lowest bio-oil yield was obtained with the addition of NiFe2O4 (1) catalyst. According to the obtained results, the ability of nickel and cobalt ferrites to catalyze deoxygenation reactions depends on the crystallite size. The nickel or cobalt ferrites with smaller crystallite size (15-22 nm) show a higher ability to catalyzed dehydration reaction than catalysts with larger crystallite size (45-54 nm).

Layered double hydroxides (LDHs) are materials of great scientific interest. They are used in numerous fields, such as in the pharmaceutical industry, environmental remediation, polymers, catalysis, among others, due to their anion exchange capacity. In this investigation, nine batches of LDHs were successfully produced by co-precipitation at low supersaturation. pH was maintained constant, and the aging stages of LDH were carried out at different temperatures: namely 30, 50, and 70 °C and times of 12, 18, and 24 h. The samples were characterized by X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) techniques in order to evaluate the crystallinity and the presence of impurities in the materials obtained. The experimental results revealed that the structural characteristics of LDH (such as lattice parameters and the interlayer spacing) were not affected by temperature and/or time parameters in the aging synthesis step. The crystallinity and crystallite size of the LDHs increase with rising aging temperature and time.

A new series of Ba2-xBixCoRuO6 (0.0 ≤ x ≤ 0.6) hexagonal double perovskite oxides have been synthesized by a solid-state reaction method by substituting Ba with Bi. The polycrystalline materials are structurally characterized by the laboratory X-ray diffraction, synchrotron X-ray, and neutron powder diffraction. The lattice parameters are found to increase with increasing Bi doping despite the smaller ionic radius of Bi3+ compared to Ba2+. The expansion is attributed to the reduction of Co/Ru-site cations. Scanning electron microscopy further shows that the grain size increases with the Bi content. All Ba2-xBixCoRuO6 (0.0 ≤ x ≤ 0.6) samples exhibit p-type behavior, and the electrical resistivity (ρ) is consistent with a small polaron hopping model. The Seebeck coefficient (S) and thermal conductivity (κ) are improved significantly with Bi doping. High values of the power factor (PF ∼ 6.64 × 10-4 W/m·K2) and figure of merit (zT ∼ 0.23) are obtained at 618 K for the x = 0.6 sample. These results show that Bi doping is an effective approach for enhancing the thermoelectric properties of hexagonal Ba2-xBixCoRuO6 perovskite oxides.

Among the Iron-Based Superconductors, the 1144 family attracted significant attention due to the intriguing intrinsic properties exhibited by single crystals, such as high critical fields and critical currents. Polycrystalline compounds, however, are influenced by the non-ideal nature of the material. In this work, we report the superconducting properties at high magnetic fields up to 17 T of Ca/K-1144 bulk polycrystalline compounds obtained via a mechanochemically assisted synthesis route. The material exhibits a significant robustness of intrinsic features such as the superconducting transition onset, varying from approximately 35 K in the absence of the field to approximately 33 K at 17 T. Broadening phenomena of both resistive and magnetic transitions testifies however the presence of granularity issues, most likely due to extrinsic factors such as oxidation, porosity and random orientation of the crystallites.

The design of portable filtration device with electrostatic filter and description of its work, which provides the trapping efficiency about 99.5% and fractionation of the polydisperse aerosol to four fractions via particles’ electrical mobility, are presented. The samples of aerosol particles’ fractions are obtained under usual welding regimes by welding wire Св08Г2С in CO2 and their specific surface area, element and phase compositions, phase ratio and crystallite sizes are determined. The correlation between fraction’s element composition and its specific surface area is demonstrated – the iron content is decreased, and manganese and silicon contents are increased when specific surface area is increased. The polyphase content (Fe3O4, FeO, FeMn2O4 и a-Fe are determined) and presence of the monocrystal nanosized magnetite particles, wustite and iron-manganese spinel in the fraction samples are confirmed by the X-ray analysis. The silicon compounds in particles are in amorphous state. The possibility of utilization of the nanostructured aerosol particles are proposed as a result of experimental data analysis.

This research studied the preparation of luminescent glass aggregates prepared from soda-lime waste glass and strontium aluminate-based phosphors. The properties of the samples were determined by means of X-ray diffraction (XRD) technique, scanning electron microscopy (SEM), Archimedes’ method, and photoluminescence (PL) spectroscopy. It was found that the pore characteristics, density, and formation of crystallite phases in the glassy matrix depended on the phosphor content. The addition of fine phosphor powder tended to inhibit the glass crystallization and to reduce the apparent porosity of the aggregates. In general, the disadvantage of phosphors is their luminescent degradation under thermal attacks, which limits their use in applications involving high-temperature annealing. The phosphors, however, still had good luminescent properties and long-term stability with the sintering temperature as high as 750°C. The results indicated that the phosphors could be composited with glasses at high processing temperatures, enabling their widespread application.

Cobalt ferrite nanoparticles were obtained by the green synthesis method using extracts of grape peel and grape pulp. The obtained samples have been investigated by means of X-ray diffraction (XRD) analysis, scanning electron microscope (SEM), and Mossbauer spectroscopy. All samples contain pure CoFe2O4 with the cubic spinel structure of the space group Fd3m. XRD analysis indicates that cobalt ferrite nanoparticles synthesized using grape peel extract and grape pulp extract have crystallite sizes of ~ 5 and ~ 25 nm, respectively. Cation distribution and crystalline structure parameters of the samples were calculated on the basis of Mossbauer spectroscopy data. After annealing, the CoFe2O4 sample obtained with grape pulp extract has a higher degree of inversion than that obtained with grape peel extract. The decrease in the degree of inversion is related to a decrease in the average size of crystallites. The CoFe2O4 sample synthesized using grape peel extract is a more active catalyst for the decomposition of hydrogen peroxide. The first-order rate constants are 1.11·10−4 s−1 and 3.43·10−4 s−1 for the CoFe2O4-pulp and CoFe2O4-peel samples, respectively. A 100 mM H2O2 solution was decomposed to 97.4%. The surface morphology of the cobalt ferrites remains unchanged after the catalytic decomposition of H2O2. The synthesized cobalt ferrites can be used in Fenton processes as stable magnetic catalysts.

Chemical vapor deposition (CVD)-grown graphene films on Cu foils, exhibiting fine scalability and high quality, are still suffering from the adverse impact of surface contamination, i.e., amorphous carbon. Despite the recent successful preparation of superclean graphene through Cu-vapor-assisted reactions, the formation mechanism of amorphous carbon remains unclear, especially with regard to the functions of substrates. Herein, we have found that the crystallographic orientations of underlying metal substrates would determine the cleanness of graphene in such a way that slower diffusion of active carbon species on as-formed graphene-Cu(100) surface is the key factor that suppresses the formation of contamination. The facile synthesis of clean graphene is achieved on the meter-sized Cu(100) that is transformed from the polycrystalline Cu foils. Furthermore, a clean surface of graphene on Cu(100) ensures the reduction of transfer-related polymer residues, and enhanced optical and electrical performance, which allows for versatile applications of graphene in biosensors, functioning as flexible transparent electrodes. This work would offer a promising material platform for the fundamental investigation and create new opportunities for the advanced applications of high-quality graphene films.

The inorganic nanomaterial plays a crucial role in bone defect repair. Nano hydroxyapatite (nHAp) is the most important inorganic substance that closely resembles the mineral component of natural bone. This study focuses on the synthesis of nHAp Ca10 (PO4)6 (OH) 2 from snail shells using dicalcium phosphate dehydrate (CaHPO4 .2H2O, DCPD) at a mole ratio of 4:3 ball milled for 4 h at 150 rpm. The powder is then heat treated at 800°, 900°, and 1000 °C at a rate of 10 °C/min. The crystallite sizes and lattice strain on the peak broadening of the nHAp are studied using the Scherer and Williamson Hall method. The crystallite sizes of nHAp ranges from 16.05 to 21.40 nm using the Scherer method, and from 13.45 to 18.34 nm using the Williamson Hall method, with lattice strain ranging from e = 1.24 to 0.76 are analyzed. The porosity of nHAp obtained from snail shell is ranged between 81.5 and 84.5 %. It has been enhanced with bio inert ceramics of SiO2 to boost the mechanical properties of nHAp, which has low fracture toughness and a lack of flexibility. The co-precipitation method has been used to develop the composites of nHAp/SiO2/chitosan with varying weight percentages. XRD, SEM with EDAX are used to determine the morphology of nHAp particles. The porosity of nHAp/SiO2/chitosan varies between 78.65 and 85.25 %. The compressive strength of SiO2-enhanced nHAp/chitosan has reached 43.26 MPa. The tribological behaviour of SiO2 reinforced nHAp/chitosan at various wt ratios of 10 %, 20 %, and 30 % has been studied using three factors at three levels in a L9 orthogonal array. The results of the analysis of variance (ANOVA) and grey relational analysis (GRA) have revealed that increasing the amount of adding SiO2 with nHAp/chitosan composite and the sliding load as well as speed have a significant impact on the tribological performance of the hybrid composites. The multi-response tribological performance is improved significantly when 30 % wt SiO2 is added. The SEM analysis of the worn surfaces has confirmed that the both the delamination wear mechanism and the abrasive wear are reduced, as the amount of SiO2 in the composites is increased. The nHAp/SiO2/chitosan results are comparable to human cancellous bone.

In this work, BiFeO3 and BiFeO3-CoFe2O4 bioceramic compounds were investigated and their photoluminescence (PL) characteristics and antimicrobial activity were compared in detail. The crystallite size, crystalline strain, and optical band gap of the compounds were estimated using the Williamson-Hall (W-H) plot, which was derived from powder x-ray diffraction patterns. The W-H plot revealed that the crystallite size increased and the crystalline strain value decreased for the BiFeO3-CoFe2O4 when compared to pure BiFeO3. The formation of a binary phase structure was confirmed by the Raman spectrum of the synthesized composite material. In the PL analysis, weak PL visible emission bands were observed for both the pure and composite samples, indicating that fewer oxygen vacancy defects occurred. The antimicrobial activity of pure BiFeO3 and BiFeO3-CoFe2O4 was investigated in detail, and the results are discussed.

Nanolaminated graphene/metal composites possess many outstanding mechanical properties due to the high load-bearing capacity of graphene. Considering that actually prepared graphene is usually poly...

This study proposes to characterize the effect of long-term thermal cycling on transformation temperatures and thermodynamic parameters of polycrystalline CuAlBeCr shape memory alloy. Structural, morphological and thermal characterizations were performed. The samples were submitted up to 1000 cycles using a dual-bath thermal cycler apparatus. The results show that the thermal cycling has a considerable impact on the transformation behavior of the alloy. Up to 500 cycles, the alloy experienced a one-stage reverse martensitic transformation; after this, it was split into two reactions. From 100 cycles, an increase in temperature ranges ( $${A}_{\text {f}}-{A}_{\text s}$$ ) values of the reverse martensitic transformation was observed, associated with the increase in elastic energy. Our study expands the spectrum of knowledge regarding thermal and structural properties, for CuAlBe system alloys, indicating the thermal cycling conditions to which the alloy must be subjected in order to preserve the characteristics required in a given practical application.

In the presence of magnetic field, reducing the loss in temperature coefficient of resistance (TCR) and increasing metal−insulator transition point (TMI) to room temperature are the most important concerns for the application of perovskite manganites in high−precision thermistors. Based on emerging evidence, relevant factor to address these problems lies in the interaction between Jahn−Teller (JT) distortion and magnetic field, which results in spin−orbital coupling (SOC) effect and significantly influences TCR and TMI. In this work, we studied the magnetic field induced SOC effect in polycrystalline La1−xCaxMnO3 (x = 0.225–0.45) materials synthesized via sol−gel technique. Compounds undergo the JT distortions with increasing Ca dopant content, and the most pronounced distortion of 0.0144 at x = 0.40 is correlated with a basal−plane distortion mode. All samples exhibit TMI values between 262 K and 288 K, indicating the enhancement of doping−induced double−exchange interaction. In the magnetic field of 1 T, SOC effect sufficiently suppresses the deterioration of TCR caused by deficient magnetization in La0.6Ca0.4MnO3 to a value of 2.9%·K−1 at room temperature (287 K).

An eco-friendly preparation technique was used to synthesize zinc oxide (ZnO) from Hibiscus rosa-sinensis extract. In addition, titanium dioxide (TiO2) was combined with ZnO in a nanocomposite. The structural investigation was done by x-ray diffraction (XRD) and the hexagonal symmetry of ZnO was detected. The calculated crystallite size of ZnO increased from 31.3 to 34.4 nm. Furthermore, functional groups of organic residues were detected by chemical analysis of Fourier transform infrared spectroscopy (FTIR). The rod grains of ZnO and TiO2 were detected by scanning electron microscope (SEM). Further, ZnO grains increased in length from 0.87 to 4.5 μm. Besides, the width increased from 0.27 to 2 μm (from ZnO to ZnO/TiO2 respectively). Furthermore, TiO2 grains decreased in length from 536 to 337 nm, while the width decreased from 136 to 122 nm. A transmission electron microscope (TEM) was used to investigate the particles of ZnO/TiO2 composite. ZnO particles were detected as ellipsoidal with length and width around 123 and 91 respectively. Besides the sphere particles of TiO2 with a diameter around 25 nm. The eco-friendly composites without harmful chemicals could be suggested for biological applications. The inhibition zone values of E. coli and S. aureus microorganisms was 61.4 ± 3.6 and 39.6 ± 4.4 and has been increased by by doping by TiO2 to 82.3 ± 6.7 and 54.3 ± 2.8.

The results of ellipsometric, x-ray, and spectral studies of In2O3 films deposited by dc-magnetron sputtering on Al2O3 (012) substrates are presented. The experimental data are interpreted in terms of a three-layer model of the fi lm. It is assumed that large particles of the material are formed on the surface of the substrate at the beginning of the deposition process. The size of the crystallites then decreases, and they fill the gaps between the larger particles, after which the film formation goes into the stationary mode. It was shown that there is a transition layer with a band gap of 1.39 eV, a refractive index of ~3, and thickness of 25 nm at the interface between the film and the substrate. The properties of this layer do not depend on the deposition time.

Lead acetate (PbAc2) offers exceptional advantages as lead (Pb2+) source for solution processing of homogeneous and pinholes-free MAPbX3 perovskite films over large areas at low temperatures for photovoltaic applications. However, PbAc2-derived MAPbI3 films usually exhibit small crystallites (

FeSe superconducting bulks with different Fe contents were prepared by high energy ball milling aided sintering process followed by a post annealing process in low oxygen atmosphere. The influences of Fe content, annealing temperature and oxygen partial pressure have been systematically studied. It was found that both the critical temperature and superconducting phase volume ratio have been obviously improved with annealing. However, the effect of oxygen annealing process on FeSe polycrystalline bulks was different with that on FeSe single crystals. In polycrystalline bulks, the annealing process could further promote the phase transition from nonsuperconducting hexagonal δ-FeSe phase to superconducting tetragonal β-FeSe phase. Meanwhile, the chemical composition uniformity has also been enhanced with no obvious FeOδ phase detected by X-Ray Diffraction. With optimized annealing process under the oxygen partial pressure of 5% at 400 °C for 10 h, FeSe superconducting bulks have reached the critical temperature of 9.1 K.

Al2O3 thin film was deposited on Gorilla glass using an aerosol deposition method to improve the mechanical property of cover glass for mobile electronic device. The deposited Al2O3 film (approximately 1 μm thick) was a polycrystalline structure and showed a high light transmittance of approximately 90% in the visible light region. The CIE color space (L*a*b) measurement also showed a characteristic corresponding to the acceptable optical range of the cover glass. Further, it was confirmed that the bending strength improved by 10 %, as compared with bare Gorilla glass (from 6970 kgf/cm2 to 7704 kgf/cm2), and the Vickers hardness increased to approximately 1700–2000 HV, as compared with that of Gorilla glass (

In this paper, we report synthesis of pure SrMoO4, Sm3+ (1 at%–5 at%) doped SrMoO4 and Bi3+ (1 at%–3 at%) co-doped in 4 at% Sm3+ doped SrMoO4 (SrMoO4:4Sm3+) phosphors by solution combustion method. The X-ray diffraction (XRD) analysis reveals the tetragonal phase of all samples, also Bi3+ co-doping supports crystallite size growth and reduces lattice strain. Absorption analysis of Sm3+ doped SrMoO4 ascertains a decrease in band gap and Bi3+ co-doping confirms the emergence of an absorbance peak at around 308 nm attributed to Bi3+ energy levels. Photoluminescence (PL) analysis ascertains an increase in emission peaks for Sm3+ doped SrMoO4 up to 4% concentration, which are attributed to an electron transition from 4G5/2 to 6HJ (J = 5/2, 7/2, 9/2, and 11/2) energy levels of Sm3+ ions. We have explained the effects of Bi3+ co-doping on the luminescence of Sm3+ doped SrMoO4. The reduced microstrain and increased crystallinity of the phosphors as a result of Bi3+ co-doping and their correlation with the luminescence of Sm3+ ions are discussed.