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First principles calculations show that Bi–C monolayers are an excellent candidate for alkali metal ion batteries.

Room temperature ferromagnetism with the doping of magnetic ions in the semiconducting host is the fundamental criterion for the potential use of spintronics material. In the present study, pure and (Fe, Tb) co-doped ZnO nanoparticles were well-prepared via the co-precipitation method, and corresponding microstructural, magnetic, and optical properties were investigated. The formation of Wurtzite hexagonal crystal structure of pure and doped ZnO was confirmed by X-ray diffraction (XRD) studies. No secondary phase was detected in all samples. Microstructural analysis reveals the spherical morphology of synthesized particles with the average size in the nanometer range. Fourier transforms infrared spectra show Tb–Zn–O stretching at 550 cm−1. Optical absorption spectra show that the bandgap decreases and the absorption band slightly shift toward the visible region with increasing Tb doping, which may be due to the transfer of charge between the Tb ion 4f level and ZnO valance band. The photoluminescence (PL) spectrum exhibits a strong emission in the visible range, and PL emission intensity decreases with increasing Tb concentration and is anticipated to be due to the low recombination rate of electron–hole pairs. Most importantly, the room temperature ferromagnetism (RTFM) was observed in the doped ZnO nanoparticles, ascribed to the bound magnetic polaron (BMP) mechanism. The optical and magnetic outcome demonstrates that prepared (Fe, Tb) co-doped ZnO based dilute magnetic semiconducting (DMS) material are potential candidates for spintronics applications.

According to World Health Organization (WHO) survey, air pollution has become the major reason of several fatal diseases, which had led to the death of 7 million peoples around the globe. The 9 people out of 10 breathe air, which exceeds WHO recommendations. Several strategies are in practice to reduce the emission of pollutants into the air, and also strict industrial, scientific, and health recommendations to use sustainable green technologies to reduce the emission of contaminants into the air. Photocatalysis technology recently has been raised as a green technology to be in practice towards the removal of air pollutants. The scientific community has passed a long pathway to develop such technology from the material, and reactor points of view. Many classes of photoactive materials have been suggested to achieve such a target. In this context, the contribution of conjugated polymers (CPs), and their modification with some common inorganic semiconductors as novel photocatalysts, has never been addressed in literature till now for said application, and is critically evaluated in this review. As we know that CPs have unique characteristics compared to inorganic semiconductors, because of their conductivity, excellent light response, good sorption ability, better redox charge generation, and separation along with a delocalized π-electrons system. The advances in photocatalytic removal/reduction of three primary air-polluting compounds such as CO

Full potential linearized augmented plan wave (FP-LAPW) method based on density functional theory (DFT) is employed to investigate the structural, optoelectronic, elastic and magnetic properties of cubic XAlO3 (X = Nd, Gd) perovskites. The optimized unit cells have been used to expose the thermodynamic stability in the ferromagnetic ground state, which is further verified in terms of enthalpy of formation (ΔHf) and cohesive energy. The spin polarized band structure and density of states illustrate that NdAlO3 perovskite has a half metallic character, and GdAlO3 has a semiconductor nature. The bulk modulus, elastic constants, Poisson's ratio, shear modulus, anisotropy and Young's modulus are also determined. The calculated magnetic moments of cubic NdAlO3 and GdAlO3are 3 μB and 7 μB, respectively and the magnetization is largely originated from Nd and Gd atoms. Furthermore, the optical parameters like reflectivity, optical conductivity, dielectric constants, absorption coefficient and refractive index are also investigated. The results suggest that these compounds could be promising materials for spintronic and optoelectronic devices.

The spin-polarized electronic band structures, density of states and optical and magnetic properties of dilute magnetic semiconductors (DMSs) Cd1−xMnxS with 6.25%, 12.5% and 25% concentrations of Mn have been studied by using ab initio calculations. The electronic band structures show half metallic ferromagnetic (HMF) behaviour with direct band gap at Γ symmetry point. The calculated values of band gaps are 0.8 eV, 0.99 eV, 1.3 eV and 1.5 eV for CdS, Cd0.9375Mn0.0625S, Cd0.875Mn0.1250S and Cd0.75Mn0.25S, respectively. The energy gap of CdS was found to increase by doping with transition metal impurity. The addition of the dopant atoms in CdS turns it into a p-type semiconductor. This half metallic character makes these compounds a potential candidate for spintronics applications. In optical properties, the role of Mn concentration on the absorption coefficient, optical conductivity, refractive index, extinction coefficient and dielectric function has been investigated. The total magnetic moment is found approximately 5.000 μB per dopant atom for Cd1−xMnxS (x = 6.25%, 12.5% and 25%). This value indicates that every Mn impurity adds no hole carriers to the perfect CdS crystal.

In the present work, Co-doped SiO2 nanoparticles are synthesized via the sol-gel method. X-ray diffraction (XRD) analysis indicates the formation of amorphous SiO2 nanoparticles and some additional peaks corresponding to the cobalt oxide (Co2O3) phase are also observed. The scanning electron microscope (SEM) analysis shows the spherical-shaped nanoparticles having particle size of 130–150 nm. Fourier transform infrared (FTIR) spectroscopy results show various absorption bands corresponding to typical stretching and/or bending vibrational modes. UV–Vis spectroscopy results indicate the low energy charge migration between the oxygen ligands and Co2+ ion in tetrahedral symmetry. By photoluminous spectroscopy analysis, the intensity of the blue band was observed to be enhanced significantly with the increasing Co concentration. This might be due to the formation of more defects sites in the host matrix. Moreover, the dielectric constant and AC conductivity of SiO2 nanoparticles were also influenced remarkably by increasing Co concentration.

This article presented studies on structural, magnetic, and electrical properties of SiO2 coated GaFeO3 (GaFeO3@SiO2) nanoparticles. A standard core-shell technique was used for the synthesis of GaFeO3@SiO2 nanoparticles. The X-Ray diffraction confirmed that both samples are pure phase with orthorhombic crystal symmetry that belongs to Pc21n space group. Further structural analysis indicates that SiO2 coating has anisotropically compressed the lattice of GaFeO3 nanoparticles. The coating of amorphous SiO2 layer has been confirmed from the TEM results. It is also found that the magnetic properties slightly reduced with SiO2 coating, which confirm the non-magnetic nature of SiO2. More importantly, the SiO2 layer suppresses the leakage current and AC conductivity of GaFeO3. Such improved electrical behavior can be related to the accumulation of charges at the core–shell interface. These results demonstrate that the core–shell technique is a promising alternative to improve the electrical properties of multiferroic GaFeO3.

Vertical magnetization shift (VMS) is a special type of exchange bias effect that may lead to a revolution in future ultrahigh-density magnetic recording technology. However, there are very few reports focusing on the performance of VMS due to the unclear mechanism. In this paper, a giant vertical magnetization shift (ME) of 6.34 emu/g is reported in the Ni50Mn36Ga14 alloy. The VMS can be attributed to small ferromagnetic ordered regions formed by spin reconfiguration after field cooling, which are embedded in an antiferromagnetic matrix. The strong cooling-field dependence, temperature dependence, and training effect all corroborate the presence of spin reconfiguration and its role in the VMS. This work can enrich VMS research and increase its potential in practical applications as well.

In the present paper, the magnetocaloric effect (MCE) of ${\mathrm{NdCo}}_{2\ensuremath{-}x}{\mathrm{Fe}}_{x}$ ($x\phantom{\rule{0.28em}{0ex}}=\phantom{\rule{0.28em}{0ex}}0$, 0.2, 0.4, 0.6) compounds was investigated by magnetization measurements. The temperature-dependent high-resolution synchrotron x-ray diffraction study shows a magnetostructural transition from the paramagnetic cubic phase to the ferromagnetic tetragonal phase below their Curie temperatures. Differential scanning calorimetry analysis shows the absence of thermal hysteresis, indicating the second-order nature of the magnetostructural phase transition in these compounds. The maximum values of magnetic entropy change ($\mathrm{\ensuremath{\Delta}}{S}_{M}$) and wide operating temperature (OT) are obtained under a field change of 5 T, which are 7.33 ${\mathrm{Jkg}}^{\ensuremath{-}1}{\mathrm{K}}^{\ensuremath{-}1}$, 6.45 ${\mathrm{Jkg}}^{\ensuremath{-}1}{\mathrm{K}}^{\ensuremath{-}1}$, 5.71 ${\mathrm{Jkg}}^{\ensuremath{-}1}{\mathrm{K}}^{\ensuremath{-}1}$, 4.70 ${\mathrm{Jkg}}^{\ensuremath{-}1}{\mathrm{K}}^{\ensuremath{-}1}$ and 78 K, 82 K, 85 K, 92 K for $x$ = 0, 0.2, 0.4, and 0.6, respectively. The corresponding values of relative cooling power (RCP) are 529.96 ${\mathrm{Jkg}}^{\ensuremath{-}1}$, 497.25 ${\mathrm{Jkg}}^{\ensuremath{-}1}$, 470.55 ${\mathrm{Jkg}}^{\ensuremath{-}1}$, and 428.31 ${\mathrm{Jkg}}^{\ensuremath{-}1}$. The observed wide OT range and large RCP values are comparable with Gd, ${\mathrm{Gd}}_{5}{\mathrm{Ge}}_{2}{\mathrm{Si}}_{2}$, and some rare-earth-based giant magnetocaloric materials, making this series of compounds suitable for magnetic refrigeration.

The electronic, magnetic and optical properties of Ni-doped CdSe diluted magnetic semiconductors have been explored by density functional theory-based FPLAPW method as incorporated in the Wien2k code. The band structure and density of states analysis for up spin channel and down spin channel illustrate half-metallic ferromagnetic behaviour. The calculated values of the band gap in an insulating channel (down spin channel) increases from 0.4 to 0.8 eV with increasing the doping concentration of Ni from 6.25 to 25%. The magnetic moment of Ni decreases and magnetic moment on nonmagnetic side increases, which shows the strong pd-hybridization. Furthermore, the optical properties are characterized in terms of dielectric constants, refractive index, extinction coefficient, absorption coefficient and optical loss factor. The static values of the dielectric constant and refractive index are consistent with each other.

Transition-metals chromium (Cr) and iron (Fe) doped ZnO nanoparticles are synthesized by sol-gel auto-combustion and characterized by different techniques. X-ray diffraction (XRD) analysis reveals that the synthesized nanoparticles have a typical hexagonal wurtzite structure. The crystallite size measured by Scherrer's formula was in the range of 36–38 nm at different doping concentrations. The scanning electron microscope (SEM) results show the nano-sized nanoparticles with well-defined boundaries are observed. Fourier transform infrared (FTIR) spectra show a wide absorption band at 1589 cm−1 for whole composition range, corresponding to the stretching vibration of zinc and oxygen Zn O bond. A decrease in optical band gaps from 3.20 eV for ZnO to 3.16 eV for Zn0.95Cr0.05Fe0.05O nanoparticles was observed by UV–Vis spectroscopy analysis. The field-dependent magnetization M-H loops measured by using vibrating sample magnetometer (VSM) reveal that diamagnetic behavior of ZnO nanoparticles changed into ferromagnetic depending on the doping concentration. Our results provided an active route to improve magnetic properties of the ZnO nanoparticles, which may get considerable attention in the coming days.

Coal fly ash (CFA) based-copper ferrite nanocomposites were fabricated, characterized, and applied for the photocatalytic degradation of Methyl Orange (MO) dye. The hydrothermal synthesis route was opted for the fabrication of pristine copper ferrite nanoparticles and its CFA nanocomposites. The prepared photocatalysts were analyzed in terms of structural, surface morphology, chemical state analysis, elemental composition, and optical response. The photocatalytic activity of nanocomposites was investigated sequentially under ultraviolet light (254 nm) and influencing parameters (pH, H2O2 dose, photocatalyst content, dye initial concentration, irradiation time) were studied. The optimized conditions for photocatalytic degradation were found at pH = 5, composite dose = 100 mg/L, H2O2 = 10 mM using CFA nanocomposite and the dye was efficiently degraded within 60 min. The best degradation efficiency of ~98% was achieved using CFA-CuFe2O4 (1:1) under the optimized conditions. The key reactive species ( OH, h+, and e−) for photocatalytic degradation were determined by a radical scavenging experiment and O H radicals were found to be the most effective ones. The kinetic study of Fenton oxidation processes was conducted using Behnajady-Modirshahla-Ghanbery (BMG) kinetic model. Response surface methodology was the statistical tool for the assessment of interaction effect among experimental variables.

Soft magnetic metallic materials are the key components in generators, motors and transformers. The Curie temperatures of currently used soft magnetic metallic materials limit their applications in high-temperature environments. In this work, we tuned the bcc/fcc ratio through modifying the Co content, thus obtaining near-zero magnetostriction and improved soft magnetic properties in the magnetostrictive system Fe100-xCox (70≤x≤93) alloys with high Curie temperature. With the increase of Co content, we observed the evolution of three crystal structures from bcc to fcc and three types of magnetostriction curves, ∧-type, ∨-type and M-type, which can be well interpreted by the domain-switching model. The optimum composition Fe20Co80, corresponding to the coexistence of bcc & fcc phases, exhibits magnetostriction of -3 ppm, a coercive field of 0.18 kA/m and saturated magnetization of 183 Am2kg−1. Our study provides an effective route to design magnetic functional materials with zero magnetostriction.

In the present work, the optical, electronic and thermoelectric (TE) characteristics of NaTaO3 are investigated with implementation of pressure ranging 0 to 140 GPa.The calculations were done in the framework of density functional theory (DFT) within Perdew-Burke-Ernzerhof generalized gradient approximation (PBE-GGA) scheme implemented within WIEN2K package. The semiconducting Eg behavior of NaTaO3compound has been revealed at all applied pressures. Results indicated that the value of Eg increments from 2.29 eV (0 GPa) to 2.82 eV (140 GPa), however, the characteristics of Eg transformed to direct from indirect with the increment in pressure. The optical characteristics are also explored in the form of dielectric constants, reflectivity (R (ω)) and absorption coefficient (α (ω)). Moreover, the TE characteristics are also investigated. TE and optical features disclosed that NaTaO3 is a good candidate for optical and TE devices.

The full potential linearized augmented plan wave method (FP-LAPW) within density functional theory (DFT) is applied to examine the structural, electronic, magnetic and optical characteristic of barium based perovskitesBaXO3(X = Th, U) in cubic phase. BaThO3 and BaUO3compounds are stable in the non-magnetic and ferromagnetic ground states, respectively. The BaUO3compound showed the half metallic ferromagnetic (HMF) behavior, while BaThO3 revealed the insulating behavior with a band gap (Eg) of 3.16 eV. The spin down region has a Eg of 3.39 eV and spin up channel shows the metallic character for BaUO3 compound. The dielectric function ɛ (ω), extinction coefficient k (ω), refractive index n (ω), reflectivity R (ω), optical absorption α (ω) are also calculated. Results indicate that BaUO3 is useful for spintronics and optoelectronic devices whereas both compounds are suggested to be suitable for optoelectronic application.

The optical, band structure (BS) and thermoelectric (TE) characteristics of of cubic BaZrO3 perovskite are examined under a pressure range of 0−21 GPa, through Perdew-Burke-Ernzerhof generalized gradient approximation (PBEsol-GGA) scheme in the framework of density functional theory (DFT). The calculated BS and density of states (DOS) revealed the semiconducting behavior of BaZrO3at all applied pressures. However, the nature of the Eg is changed from indirect to direct as the pressure elevated from 0 to 21 GPa. Furthermore, the optical characteristics like reflectivity R(ω), absorption coefficient α(ω), dielectric constant e(ω), refractive index n(ω), extinction coefficient k(ω) and optical conductivity σ(ω) are also studied under various pressures. Finally, the TE featurse in terms of electric conductivity (σ), thermal conductivity (K), Seebeck coefficient (S) and power factor (PF) are calculated using the BoltzTraP code. The results of optical and TE properties revealed the possible use of BaZrO3 material for TE and optical applications.

The first principles calculation is implemented to predict the phase stability, optical activities and magneto-electronic characteristics of cubic MAlO3 (M = Ce, Pr) perovskites. The optimized structural parameters authenticate the stability of the ferromagnetic state, and also it is confirmed by enthalpy of formation (ΔHf). Stability of MAlO3 compounds is verified with the help of tolerance factor ( τ ) in the cubic phase. The density of states (DOS) and spin polarized band structure (BS) elucidate the ferromagnetic half metallic (HM) type of MAlO3 compounds, with Ce/Pr-f states play a major role. The calculated value of magnetic moment increases from cubic CeAlO3 (1 μB) to PrAlO3 (2 μB), and Ce and Pr atoms enormously contribute in magnetization. Moreover, various optical parameters such adsorption coefficient, dielectric constants, reflectivity, optical conductivity and refractive indexare also studied. The outcomes recommend that these perovskites might be suitable candidates for optical and spintronic devices.

FP-LAPW method is used to determine the electronic, optical, and thermoelectric characteristics of the SrZrO3. The band structure (BS) plot reveals indirect (Γ-M) energy gap for 0 GPa and 10 GPa. However, at 30 GPA, it converted to direct band gap. The total and partial density of states (PDOS) described the contribution of each atom in the material. The optical characteristics such as complex dielectric function, extinction and absorption coefficients, refractive index, and reflectivity are studied under pressure. The highest absorption peaks are originated due to the direct optical transition O-2p states to the Zr-4d orbitals. Moreover, thermoelectric properties are also investigated with respect to temperature. The Seebeck coefficient and electrical conductivity rises with the upsurge in pressure upto 40 GPa and highest value of ZT is 0.73. The simulated outcomes disclose that SrZrO3is a promising applicant for thermoelectric and optelctronic devices.

The present study was conducted to develop buckwheat cookies supplemented with wheat flour.Buckwheat and wheat flour were examined for their proximate composition. Buckwheat flour contained11.6% moisture, 15.79% crude protein, 1.81% crude fat, 1.83% ash, 0.70% crude fibre content and 68.27%NFE, while wheat flour contained moisture content 13.12%, crude fibre content 1.93%, crude fat 1.42%,crude protein content 12.53%, ash content 1.57% and 69.43% NFE, respectively. Wheat flour was incor-porated into buckwheat flour at 10, 20, 30, 40 and 50% ratio to make composite flour and the developedcookies were analysed for quality evaluation. Supplementation of wheat flour significantly influenced theproximate and mineral composition of buckwheat flour based cookies. Moisture contents, crude fibrecontents and NFE (Nitrogen Free Extract) increased, whereas crude fat, crude protein and ash contentsdecreased. Mineral contents (Fe, Ca, K, Zn and Mg) of developed buckwheat cookies decreased withincrease in wheat flour supplementation levels. Sensory characteristics of supplemented cookies increasedwith increase in supplementation levels of wheat flour and were acceptable by judges in terms of test,colour, texture and overall acceptability. Cookies developed from C 50% C supplementation level of wheatflour got maximum scored points while C0 control C0 was found to be more nutritious and gluten freehaving more crude protein and mineral contents when compared to supplemented cookies.

The structural, magnetic and thermal features of Strontium (Sr) and iron doped (LaMnO3) have been studied to optimize their Hyperthermia efficiency. Citrate-gel technique was employed to synthesize (La1-xSrxMnO3) (x = 0.27, 0.3& 0.33) and a new composite (La1-x Srx Mn1-yFeyO3) (x = 0.27, y = 0.03). XRD patterns showed good polycrystalline structures with crystallite size up to 16 nm. HRTEM was employed to study the morphology of nanoparticles (NPs). Sodium Poly-Styrene Sulfonate (PSS) was opted to attach with (NPs), as a novel attempt, for coating purpose and FTIR showed existence of diversified peaks. Differential scanning calorimetric (DSC) studies were employed to assess the phase changes through respective heat flow mechanisms. The magnetic parameters using super quantum interface device (SQUID) showed good magnetization till 50 kȎe. Radio frequency (RF) induced field studies were employed at three different values (259.7, 327 & 518 kHz), to display comparative heating aptitudes of LSMO for hyperthermia efficacy.

In the present paper, structural, magnetic and magnetostrictive properties of Tb1−xGdxFe2 (0 ≤ x ≤ 1.0) were studied. Synchrotron x-ray diffraction (XRD) results show the non-cubic symmetry of Tb1−xGdxFe2 at room temperature and composition-induced crystallographic phase transition from rhombohedral phase to tetragonal phase. The Gd concentration dependent lattice parameters, lattice distortion and change of easy magnetic direction were detected by synchrotron XRD. With the Gd concentration increases, Curie temperature Tc increases while room temperature magnetization and magnetostriction coefficient λ111 and the anisotropy of TbFe2 decrease. The decrease in spontaneous magnetostriction coefficient λ111 with increasing Gd substitution can be understood on the basis of the single-ion model; the corresponding decrease of magnetostriction for Tb1−xGdxFe2, and the large magnetostriction value occurs on the Tb-rich side, are ascribed to decrease of λ111.

The polycrystalline Tb0.27Dy0.73-xNdxFe2 Laves phase compounds were prepared at equilibrium conditions and consequent annealing method at high pressure. Their structural, spin configuration, magnetic and magnetostrictive properties were studied. Rietveld refinement analysis of X-ray diffraction (XRD) reveals that the studied compounds possess predominantly the MgCu2-type cubic Laves phase, coexisting with a small amount of hcp-type rare-earth (RE)-rich phase and PuNi3-type REFe3 phase. The magnetization (MS) and Curie temperature (TC) decrease while the lattice parameter increases with the increase in Nd concentration. The direction of easy magnetization (EMD) accompanied by a rhombohedral distortion (λ111) was observed along [111] axis at room temperature (RT). The spin reorientation transition (SRT) occurs at low temperature, which was explained by the two-sublattice model. Based on the experimental results, a detailed phase diagram has been designed for the Tb0.27Dy0.73-xNdxFe2 Laves phase to demonstrate the different spin configurations and crystal structure. The anisotropy compensation between the Nd and Dy sublattices was realized at x = 0.1. The Nd-containing Tb0.27Dy0.63Nd0.1Fe2 Laves phase compound shows large low-field polycrystalline magnetostriction (λS) and large spontaneous magnetostriction coefficient (λ111~1.7 × 10−3), which may make it a good magnetostrictive material. Our results indicate that the substitution of Nd by Dy in Tb0.27Dy0.73Fe2 compounds is beneficial for the improvement of magnetostrictive properties. The present study might be useful to design Nd-based magnetostrictive materials for technological applications.