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The effect of 2MeV energy electrons with fluences from $0.5\times 10^{17}$ to $4.0\times 10^{17}$ electron/cm² on the crystal structure, surface morphology, absorption spectrum, band gap, Raman spectrum and microhardness of ZnS crystal was investigated. The crystal structure of ZnS is face-centered cubic with space group F-43m. Upon irradiation with a fluence of $4\times 10^{17}$ electron/cm², the unit cell parameter decreased by 0.0195Å, and the coordinates of the Zn${}^{+2}$ ions were changed. Irradiation with fluences ranging from $0.5\times 10^{17}$ to $4\times 10^{17}$ electron/cm² increased crystallite size from 20nm to 28nm. The study of the surface morphology of the ZnS single-crystal revealed that irradiation caused a reduction in both the width ($R_a$) and height ($R_z$) of the surface roughness. The band gap of the ZnS single-crystal decreased from 3.521 to 3.506eV when irradiated with fluence electrons from $0.5\times 10^{17}$ to $2.5\times 10^{17}$electron/cm². Raman spectrum observations showed an increase in the longitudinal optical (LO) mode peak (350cm${}^{-1}$) intensity following the irradiation of ZnS single-crystal with electrons. The microhardness of the ZnS single-crystal showed an exponential increase by 20% when irradiated with fluences from $0.5\times 10^{17}$ to $2.5\times 10^{17}$electron/cm².

Fullerene grafted poly (methylmethacrylate) polymers have been studied using X-ray diffraction and raman spectroscopy to analyze their polymeric structure. The electrical properties of prepared polymers have also been studied. The X-ray diffraction and raman spectroscopy pattern of pure buckminster fullerene (C₆₀) has been compared with prepared polymeric samples. Raman spectroscopy indicates that a structural change occurs due to grafting. The vibrations in the relative intensity of peaks and shifts in energy are observed. The lower scattering efficiency of pure fullerene (C₆₀) is observed at 1468 cm^-1.The values for poly (methylmethacrylate) are observed at 3000 cm^-1. The result show a large shift in the intense raman spectral region of fullerene-based poly (methylmethacrylate) which lies between 2500 cm^-1 and 3000 cm^-1. X-ray diffraction shows an unusual variation in crystallite size of polymeric samples. Generally it has been observed that polymers are insulators, but noticeably fullerene-based poly (methylmethacrylate) show conducting behavior.

It is shown that the replacement of a part of sulfur atoms with selenium atoms in a TlInS₂ single crystal stimulates the formation of a single-phase state with a monoclinic structure (space group $C_2$/$c)$ in TlInS${}_x$Se${}_{2-x}$ ($x=1$). Irradiation with 2 MeV electrons and a fluence of $2\times 10^{17}$ electron/cm² of powder TlInS${}_x$Se${}_{2-x}$ ($x=1$) leads to an increase in the crystallite size from 56.5 nm to 65 nm, which is most likely associated with a decrease in the interface.

The difference between the surface morphology of the synthesized TlInS${}_x$Se${}_{2-x}$ ($x=1$) single crystal and the surface morphology of the TlInS₂ single crystal is established, which consists in a decrease in the height and width of the roughness in TlInS${}_x$Se${}_{2-x}$ ($x=1$). Irradiation of a TlInS${}_x$Se${}_{2-x}$ ($x=1$) single crystal with electrons with a fluence of $2\times 10^{17}$ electron/cm² does not lead to a change in the height of the tubercle on its surface, and the average value of its width increases more than ten-fold.

The identity of the peaks in the Raman spectra of the TlInS${}_x$Se${}_{2-x}$ ($x=1$) single crystal before and after its irradiation with electrons with an energy of 2 MeV and upto a fluence of $2\times 10^{17}$ electron/cm², along with the absence of a shift of the peaks, indicates the radiation resistance of the TlInS${}_x$Se${}_{2-x}$ ($x=1$) single crystal.

In this work, reduced graphene oxide (rGO) is generated by an environmentally friendly electrochemical technique using an aqueous solution of 2.5M nitric acid (HNO₃), followed by thermal degradation at a temperature of 750^∘C. To facilitate the exfoliation process, the electrolytic cell was equipped with a continuous supply of 54V DC. The microstructure of the rGO sheet has been analyzed using field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM). The obtained results show that rGO sheets are irregularly stacked together, have a fractured surface, and porous structure. TGA analysis depicts that the total estimated weight loss was observed to be 40% because of the removal of the oxygen functionalities and volatile gases. X-Ray diffraction (XRD) analysis was used to analyze the phase purity, crystalline nature, interatomic distance as well as crystallite size of the rGO sheet. In the Raman study, the value $I_D∕I_G=0.462$, which compares the peak intensity of the D band to intensity of the G band, provides evidence that the structural component associated with the rGO is present.

Amorphous carbon nitride (a-CN_x) films were deposited on quartz substrates by newly developed surface wave microwave plasma chemical vapor deposition (SWMP-CVD) of alcohol camphoric carbon plasma source at room temperature. Then the a-CN_x films were heat-treated at various annealing temperatures (AT) in the 100–500°C range. The effects of heat treatment on the structural modifications were studied by Visible-Raman spectroscopy through the evolution of D and G peaks. The spectral evolution observed on heat-treated a-CN_x shows progressive formation of crystallites. Raman spectra have revealed the amorphous structure of as-grown a-CN_x films and the growth of nanocrystallinity upon increase of AT. These structural changes were further correlated with optical band gap and fraction of sp³ bonded carbons present, derived respectively from the UV-visible and photoelectron spectroscopy. The wide range of optical absorption coefficient characteristics is observed depending on the AT. The optical band gap of as-grown a-CN_x films is found to be approximately 2.8 eV; it gradually decreases to 2.5 eV for the films heat-treated at 300°C and then it decreases rapidly to 0.9 eV at 500°C. The results obtained are discussed and compared with the literatures.

This work presents the influence of changing Ar:N₂ gas ratio on the growth and properties of InAlN films. InAlN films were deposited on $p$-type Si(111) substrates by using magnetron co-sputtering method in 6:12, 10:10, 12:8 and 12:6 Ar:N₂ mixtures at 300${}^{\circ }$C. The surface, structural, electrical and optical properties of the deposited films were evaluated at different Ar:N₂ ratios. The grain size and film thickness were increased by increasing the Ar flow with respect to N₂. Structural characterization by X-ray diffraction (XRD) revealed an improvement in the crystalline quality of the $c$-axis-oriented InAlN film by adjusting the Ar:N₂ ratio to 12:8, however no diffraction peak corresponding to InAlN was detected at 6:12 Ar:N₂ mixture. The surface roughness of InAlN film exhibited an increasing trend whereas the electrical resistivity of the film was decreased by increasing the Ar:N₂ ratio. The bandgap of InAlN film was calculated from the optical reflectance spectra and it was found to change by changing the Ar:N₂ gas ratio. The analysis of results from this work shows that the InAlN film with improved physical properties can be obtained through reactive magnetron co-sputtering method by adjusting the Ar:N₂mixture to 12:8.

The effect of substrate temperature on growth of pulsed laser deposited copper oxide thin films has been investigated by employing Nd: YAG laser (532nm, 6ns, 10Hz) irradiation at a fluence of 8.2J/cm². XRD analysis reveals that copper oxide films deposited at room temperature are amorphous in nature, whereas films deposited at higher substrate temperatures are polycrystalline in nature. SEM and AFM analyses revealed that films deposited at substrate temperatures, ranging from room temperature to 300${}^{\circ }$C are comprised of large sized clusters, islands and particulates, whereas uniform films with an appearance of granular morphology and distinct bump formation are grown at higher substrate temperatures of 400${}^{\circ }$C and 500${}^{\circ }$C. The optical bandgap of deposited films is evaluated by UV-VIS spectroscopy and shows a decreasing trend with increasing substrate temperature. Four point probe analysis reveals that electrical conductivity of the deposited films increases with increase in the substrate temperature, and is maximum for highest growth temperature of 500${}^{\circ }$C. It is revealed that growth temperature plays a significant role for structure, texture, optical and electrical behavior of copper oxide thin films. The surface and structural properties of the deposited films are well correlated with their electrical and optical response.

This paper focuses on the synthesis and structural, optical, and magnetic characterization of Mn-doped CoFe₂O₄ nanoparticles synthesized by a simple chemical co-precipitation method. Synthesized magnetic nanoparticles were characterized by XRD, FTIR, UV-Vis, PL, TEM, VSM, and EPR spectroscopy. XRD analysis confirmed the significant reduction in the crystallite size from $\sim 17$nm to 10nm as the Mn content is increased from 0 to 1. UV-Vis spectra confirmed that the Co–Mn ferrite is a direct bandgap magnetic material that possesses an energy gap from 3.92eV to 4.33eV. FTIR vibrational frequency observed between 468 and 548 ${\text{cm}}^{-1}$confirmed the existence of metal–oxygen bond at tetrahedral and octahedral sites. Photoluminescence spectra confirmed the red emission of the samples from the peak at 680nm. TEM analysis suggests that the single domain of CoFe₂O₄ nanoparticles may vary between 38 and 72nm. Composition analysis confirmed the homogeneous mixing of Co, Mn Fe, and O atoms in the synthesized samples. The VSM study confirmed that Mn substitution favors transition from ferromagnetic to superparamagnetic. VSM analysis also confirmed the lessening in saturation magnetization and coercivity on Mn doping. The X-band electron paramagnetic resonance spectrum recorded at room temperature conveys that the superexchange interaction is increased with the increase in Mn concentration.

Superparamagnetic (SP) crystalline cobalt ferrite (CoFe₂O₄) nanoparticles are synthesized by chemical co-precipitation method. Grown nanoparticles are annealed in air at various temperatures in the range 373 K to 1173 K to understand the variation in properties in nanoregion. Physical properties are analyzed for crystalline phase, crystallite size, particle size, shape, magnetization and relaxation behavior by using various characterization techniques viz. X-ray diffractometer (XRD), transmission electron microscope (TEM), vibrating sample magnetometer (VSM) and electron paramagnetic resonance (EPR). Annealing effect on various physical properties of particles are investigated. Particles are used in the development of stable ferrofluid.

The requirement for restoring graphene’s electrical and thermal properties necessitates the implementation of reduction processes that remove oxygen atoms from the surface of graphene oxide sheets. Nevertheless, has been reported that the synthesis of graphene with a minimal oxygen content remains an obstacle in the field of graphene synthesis. The partial restoration of the initial graphene characteristics brought on by the recombination of carbon–carbon double bonds is primarily constrained by the existence of leftover oxygen atoms and lattice flaws. However, the absence of polar dioxide-based groups of function makes it difficult for the substance to disperse. Oxygen-containing functional groups also serve as reaction sites to bond active molecules to reduce graphene sheets. The literature describes many chemical methods to reduce graphene oxide for these reasons. It’s crucial to choose a chemical method that allows a thin modulation of residual oxygen content to tune the end product’s properties. This research demonstrates a synthesis mechanism for the low oxygen-containing thermally reduced graphene oxide (T-R-GO) by employing an electrochemical technique, which is then followed by thermal reduction. An environment-friendly, eco-friendly, simpler, and scalable electrochemical approach was initially used to synthesize graphite oxide. A steady power source of 24V DC (direct current) has been applied while the exfoliation process is being carried out. It has been noticed that there is a potential difference of 1V during the process of exfoliation. This difference is because the electrochemical cell creates a resistance, which results in a potential difference. Within the muffle furnace, the preoxidized graphite was subjected to a thermal reduction process at a temperature of 900${}^{\circ }$C. The microstructure, elemental composition, as well as C/O ratio (ratio of carbon and oxygen), was analyzed using field emission scanning electron microscopy (FESEM), transmission electron microscopy as well as energy dispersive X-ray (EDX). According to the results of EDX, reduction temperature serves a crucial role in the elimination of oxygen functionalities or their derived compounds. The surface topography and thermal stability analysis were analyzed using atomic force microscopy (AFM) and thermogravimetric analysis (TGA). The crystallinity and disorder in microstructure were investigated using X-ray powder diffraction (XRD) and Raman spectroscopy analysis. X-Ray data show that high-temperature annealing restored the RGO structure of the crystal. The interplanar distance is 3.824Å and the diffraction peak is 26.42${}^{\circ }$. Raman bands measured the defect’s I${}_D$/I${}_G$ ratio (intensity ratio) as 0.423. The Raman study shows that the flaws are minimal. This research offers a massive, economical, and environmentally friendly method for synthesizing graphene for use in industry.

Yttria nanoparticles are synthesized by co-precipitation method and as-prepared nanoparticles are annealed at various temperatures. The as-prepared and annealed particles are characterized by X-ray diffraction and transmission electron microscope (TEM). Here we estimated the lattice strain, crystallite size, deformation stress, and deformation energy density for annealed (800°C) yttrium oxide nanoparticles by Williamson-Hall-Isotropic Strain Model (W-H-ISM), W-H-Anisotropic Strain Model (W-H-ASM) and W-H-Energy Density Model (W-H-EDM) based on W-H plot from powder X-ray diffraction data. The shape and size of the nanoparticles are determined using TEM. The results of the estimated crystallite size of yttria nanoparticles by various methods agreed with the TEM results.

XRD pattern of $\beta$-Ga₂O₃ powder, synthesized through template-free two step hydrothermal method at low temperature thoroughly, is investigated by imposing different methods of analysis. Both crystallite sizes and micro-strains of the micro-structures are analyzed and compared. Along with the traditional Scherrer’s formula (S-average, LF and LFTZ), modified Williamson–Hall (W-H) method with UDM, USDM and UDEDM and Size-Strain Plot (SSP) method were used for the investigation. Stress and defect energy densities were calculated from USDM and UDEDM modified W-H plots of the powder sample, respectively. Detailed analysis of the crystallite size and micro-strain from different methods/models was done. Obtained crystallite sizes and micro-strains from different models were compared with the results obtained from TEM analysis. It was found that crystallite sizes obtained from UDM modified W-H analysis and SSP models well coincided with crystallite size observed from TEM micrograph.

This work focuses on the detailed crystal structure and dielectric properties of LaCrO₃ and Ni-doped LaCrO₃ (LaCr${}_{0.9}$Ni${}_{0.1}$O${}_3)$ compounds. Both the samples were synthesized via the auto-combustion route. The orthorhombic crystal structure with Pbnm space group of both the synthesized samples was confirmed using X-ray diffraction measurements. The average crystallite size of LaCr${}_{0.9}$Ni${}_{0.1}$O₃compound is 52.71nm which was determined from the Debye Scherrer formula. In Ni-doped LaCrO₃compound, the formation of Cr${}^{4+}$ ions at the octahedral sites affects the dielectric properties. Enhancement in AC conductivity in LaCr${}_{0.9}$Ni${}_{0.1}$O₃ compound is due to the hopping of charge carriers in the material.

The cubic phase of Magnesium oxide (MgO) nanoparticles is synthesized by the sol-gel method. The nanoparticles were subjected to annealing at 500^∘C to enable stress and strain analysis. Characterization of the annealed nanoparticles was performed using powder X-ray diffraction (XRD). Through analysis of the XRD peak profile, key properties, such as crystallite size, lattice strain, deformation stress, and deformation energy density, were determined. These parameters were estimated using three models such as the Williamson–Hall-Isotropic Strain Model (W-H-ISM), the Williamson–Hall-Anisotropic Strain Model (W-H-ASM), and the Williamson–Hall-Energy Density Model (W-H-EDM). The estimations were based on the W-H plot derived from the powder XRD data. The findings of this study contribute to a better understanding of the structural and mechanical characteristics of annealed MgO nanoparticles, thus informing their potential applications.