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A zirconium-based microporous metal–organic framework Zr-FA has been realized, exhibiting a high sieving separation of CO2 from N2 and CH4 under ambient conditions.

A novel CaFe2O4/CQDs 90% degradation of carcinogenic Congo red dye observed. Modification of CaFe2O4 with CQDs narrowed its bandgap.

Few layer HfS2 flakes are studied by temperature, excitation and polarization-dependent Raman spectroscopy. In contrast, the fabricated device shows considerable photodetection properties under light laser power illumination.

Herein, we present the development and characterization of Yttrium oxide (Y2O3) films and Al/Y2O3/n-Si heterojunction diodes at various substrate temperatures using a low-cost facile jet nebulizer spray pyrolysis (JNSP) technique. The X-ray powder diffraction (XRD) pattern proved polycrystalline films of Y2O3 with a cubic structure. Field emission scanning electron microscope (FESEM) images reveal very fine nanograins formation in Y2O3 films at all temperatures. Scanning probe microscopy (SPM) analysis shows very low roughness of all films. The detailed compositional/homogeneity analysis was done via energy dispersive X-ray (EDX)/e-mapping analysis. All the films exhibited a sharp absorption edge at ∼ 280 nm, and the estimated energy gap values were noticed between 4.5 to 5.5 eV. Moreover, the observed photoluminescence (PL) spectrum indicated that the intensity of emission peaks quenched ∼ 3 times, indicating the reduction of defects with substrate temperature. From the current – voltage (I-V) characteristic, the calculated ideality factor (n) value was noticed to be drastically reduced from 7.66 and 2.87 on increasing the substrate temperature. Further, the diode ideality factor, series resistance (Rs) and barrier height (ФB) were obtained from Cheung's method. The results revealed that the developed Al/Y2O3/n-Si heterojunction diode is a promising contender for optoelectronic devices.

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.

The structural, optical, and dielectric properties of pure NiO and yttrium (Y) doped NiO (Y: NiO) were studied in the present article for optoelectronic application. The pristine and different concentrations of 1.0, 2.5, 5.0, 7.5, and 10 wt.% doped Y: NiO nanoparticles (NPs) were synthesized by flash combustion route. X-ray diffraction patterns (XRD), Raman spectroscopy and scanning electron microscopy (SEM) images were used to study the structural properties of as-prepared nanoparticles. The average crystallite sizes (29.8–6.7 nm) and grains size (159.2–17.9 nm) were found to be decreased with an increase in Y contents. The dislocation density (1.12–21.75 × 10−3 1/nm2), lattice strain (2.79–12.46 × 10−3) and surface area (29.48–131.13 cm2/g) were increased on increasing Y contents. Direct optical band gaps of prepared samples were estimated using the Tauc's relation in the range of 3.52–3.37 eV. Photoluminescent spectra of prepared samples exhibit spectra at 355 nm, 451–482 nm, and 493 nm emission bands, which confirm the existence of oxygen and nickel vacancies. The improvement in the dielectric constant (143), dielectric loss (1233), and loss tangent (8.67) were observed for 5.0 wt.% Y doped NiO from the dielectric analysis of the samples. The electrical conductivities of Y: NiO NPs were also improved compared to pure NiO NPs. The improvement in the optical and dielectric properties of NiO in the substitution of yttrium (Y) can be used for optoelectronics applications.

Sensitization of the photoanode with the semiconductor quantum dot strongly affects the final performance of the device. In this work, the effect of the adsorption cycle of cadmium sulfide was analyzed for the CdS sensitizer on CdS:TiO2-based quantum dot-sensitized solar cell. The CdS sensitizer was grown on doctor blade-coated TiO2 films using successive ion layer adsorption and reaction (SILAR) method. Porous, well adherent, and pin-hole-free TiO2 films were deposited on fluorine-doped tin oxide-coated substrate. The structural, morphological, and compositional properties of TiO2 and CdS-sensitized TiO2 films were studied using UV–visible spectroscopy, X-ray diffraction, scanning electron microscopy, and energy dispersive spectroscopy. The QDSSCs fabricated using CdS sensitizer onto TiO2 photoelectrode were tested for various adsorption cycles of CdS. The influence of various SILAR cycles of CdS sensitizers on the light-harvesting ability of the porous TiO2 photoelectrode and its subsequent highest power conversion efficiency for fabricated QDSSCs were investigated.

For polymer solar cells (PSCs), the mixture of polymer donors and small-molecule acceptors (SMAs) is fine-tuned to realize a favorable kinetically trapped morphology and thus a commercially viable device efficiency. However, the thermodynamic relaxation of the mixed domains within the blend raises concerns related to the long-term operational stability of the devices, especially in the record-holding Y-series SMAs. Here, a new class of dimeric Y6-based SMAs tethered with differential flexible spacers is reported to regulate their aggregation and relaxation behavior. In their polymer blends with PM6, it is found that they favor an improved structural order relative to that of Y6 counterpart. Most importantly, the tethered SMAs show large glass transition temperatures to suppress the thermodynamic relaxation in mixed domains. For the high-performing dimeric blend, an unprecedented open circuit voltage of 0.87 V is realized with a conversion efficiency of 17.85%, while those of regular Y6-base devices only reach 0.84 V and 16.93%, respectively. Most importantly, the dimer-based device possesses substantially reduced burn-in efficiency loss, retaining more than 80% of the initial efficiency after operating at the maximum power point under continuous illumination for 700 h. The tethering approach provides a new direction to develop PSCs with high efficiency and excellent operating stability.

Hybrid hydrogels based on n-isopropylacrylamide, zwitterionic comonomer, and graphene oxide were synthesized to study their physical and mechanical properties. The compositional variation largely influenced the swelling characteristics of the hybrid hydrogels compared to mechanical properties, i.e., elongation and compression. Additionally, Rheometric swelling measurements on the swollen hydrogels were performed until they reached equilibrium showed a very low phase angle δ indicating strong covalent network, which intrun increases with increasing content of zwitterions and GO. Swelling kinetics were studied and found to follow Fickian dynamics, albeit zwitterion-containing gels showed a peculiar 2-step swelling pattern. Interestingly, differences in the swelling mechanism are also clear for the hydrogels with 2D GO (Graphene oxide) nano-fillers from its 1D nano-filler CNTs (Carbon nanotubes). In elongation, the samples break in a brittle fashion at Hencky strains ε

Nano-sized semiconductor photocatalysts are known for their promising and economical remediation approach to environmental pollution under visible light irradiation. In this study, a facile strategy was adopted to develop the zirconium oxide/cadmium sulfide nanocomposite through a co-precipitation method for degradation of three aromatic dyes under visible light. The synthesized photocatalyst was characterized using powder X-ray diffraction, Fourier-transform infrared spectroscopy, Scanning electron microscopy, UV–Visible spectroscopy, Cyclic voltammetry, and Electrochemical impedance spectroscopy. The zirconium oxide/cadmium sulfide heterostructure nanocomposite was tested for photocatalytic degradation of Direct Violet-9, Methyl Violet, and Congo Red. The composite exhibited photocatalytic degradation efficiency of 95.5%, 91%, and 84% for Direct Violet-9, Methyl Violet, and Congo Red, respectively under visible light. The high degradation efficiency of the photocatalyst for multiple dyes was found to be mainly due to the suppression of charge carrier recombination.

In this study, silver-doped natural mulberry fibers were successfully obtained by the dip-coating technique. Arrays of material consisting of synthetic compounds (organic as well as inorganic) are being utilized to impart antimicrobial functionality to textiles. Therefore, the current study for the first time attempted to establish an innovative class of textiles made up of silver-doped natural mulberry fibers. This fabric will be utilized for the fabrication of antimicrobial socks. The morphology, physicochemical and antibacterial characteristics of Ag-doped mulberry fibers were scanned via X-ray diffraction (XRD), scanning electron microscopy (SEM), electron probe microanalysis, Fourier transform infrared spectroscopy (FTIR) and antibacterial testing. SEM analysis evidently demonstrated uniform distribution of Ag on mulberry fibers and the outcome of XRD and FTIR analyses authenticated assimilation of Ag in the Ag-doped mulberry composite. The Ag-doped mulberry fibers revealed venerable antibacterial action against representative bacterium E. coli. The antibacterial analysis lead to the conclusion that the Ag-doped mulberry fiber textile has an enhanced bactericidal effect owing to the synergism of Ag and mulberry compounds. Moreover, Ag imparted an anti-odor effect on mulberry fiber. These distinctive organic–inorganic fibrous composite socks are antimicrobial, odor free and skin and environment friendly. Thus, this study recommends the use of Ag-doped mulberry fibers as a future material for the preparation of durable antibacterial new generation socks. These composite fibers can also be used as textile material for clothes such as sportswear and for medical purposes; for instance, bedcovers in hospital beds, etc.

The present study described the synthesis and assessment of different properties of ferrite-polymer composites. These composites were fabricated by the appropriate mixture of ferrite nanoparticles and polypyrrole. A versatile chemical technique known as co-precipitation was applied in the preparation of ferrite materials. The in-situ polymerization scheme was chosen to synthesize the polymeric polypyrrole base. A series of samples with zero to hundred percent ferrite contents were prepared. These include pure ferrite sample, pure polypyrrole sample, FP-1(25% ferrite, 100% polypyrrole), FP-2 (50% ferrite, 100% polypyrrole), FP-3 (75% ferrite, 100% polypyrrole) and FP-4 (100% ferrite, 100% polypyrrole). These samples were analyzed to evaluate the surface morphology, structural properties as well as magnetic properties. The shape of hysteresis loop showed the ferromagnetic nature of the synthesized composites. On the basis of the results of current study, the samples with 25% and 50% ferrite ratio may be suitable for the hyperthermia.

Pure CeO2 and Ni-doped cerium oxide (NDC) films were deposited by a facile and economic jet nebulizer spray pyrolysis (JNSP) process at 450 oC substrate temperature. Here, efforts have been done to enhance the performance of the NDC diode using various doping concentrations of Ni (0, 2, 4, and 6 wt%). X-ray diffraction revealed polycrystalline film formation with a cubic crystal structure and the crystallite size of CeO2 was increased from 10 to 21 nm on Ni doping. EDX study confirms the presence of Ni in NDC films. FESEM explicitly shows fine spherical grains-like morphology. The optical studies indicate the reduction in the bandgap of CeO2 from 3.30 to 2.86 eV on Ni doping. The Photoluminescence (PL) spectrum proves that the oxygen vacancy is created in the CeO2 thin films while doping with Ni which leads to the blue shift and intensity enhancement of emission peak. NDC film prepared with 6 wt% showed a higher electrical conductivity ~ 3.76 × 10–10 S/cm which indicates that it is suitable for photodiode fabrication. The fabricated p-Si/n-NDC photodiode works with superior parameters like ideality factor (n) and barrier height (ΦB) under dark and illuminated conditions. The saturation current (Io) of the p-Si/n-NDC diode is varied from ~ 2.69 × 10–05 to 6.57 × 10–04 A with Ni concentrations. The estimated n and ΦB values of the p-Si/n-NDC junction diode are found to be decreased from 7.6 to 2.5 and 0.72 to 0.60 eV. These outcomes indicate that the fabricated photodiode is a useful element in optoelectronic devices.

Zinc oxide and multiwall carbon nanotubes (ZnO/MWCNT) nanocomposites thick films were prepared via sol-gel screen printing procedure and followed by sintering at 550 °C. Thus, the prepared films were characterized using X-ray diffraction (XRD), scanning electron microscope (SEM), Ultraviolet–visible (UV–vis), Photoluminescence (PL), Fourier transform infrared (FTIR), Raman spectroscopy and Two-probe method. XRD analysis revealed (101) orientation for both ZnO and ZnO/MWCNT thick films with wurtzite structure. SEM studies confirmed the porous nature of ZnO film while ZnO/MWCNT films showed ZnO particles trapped in the porous MWCNT network and free from cracks. Reflectance spectroscopy showed direct transition with decreasing band gap whereas refractive index and absorption index showed appreciable variation within the band gap regime related to the change in crystallite size. FTIR profile approved the Zn–O stretching and presence of carboxylic CDC group. The PL spectrum of ZnO and ZnO/MWCNT thick films shows red shift and exhibits UV, blue and green emissions confirmed from CIE diagram. Raman spectrum shows that Raman phonons are shifted and dominated due to doping of MWCNT in ZnO matrix. Electrical properties were investigated using 2-probe method and showed a reduction in resistance on MWCNT incorporation. The novelty of current-work is the fabrication of ZnO/MWCNT through a low-cost screen printing process for the first time and the results exhibits that the bandgap of the deposited film is decreased, which in turn, play a significant role in enhancement of conductivity and colour emission for fabrication of low cost optoelectronics devices (LEDs) as compared with the pure ZnO film.

In this work, Y 1 − x Pr x F e O 3 ( 0 ≤ x ≤ 0.16 ) ceramics were fabricated via the auto-combustion sol-gel method. X-ray diffraction (XRD), scanning electron microscopy (SEM) associated with EDS mapping, and Fourier transform infrared spectroscopy (FTIR) were employed for structural and morphology analysis. The substitution of praseodymium (Pr) modified the orthorhombic structure into a hexagonal structure. However, small traces of Fe2O3 and Y2O3 appeared in all samples. The lattice constant ‘a' was increased from 3.523 to 5.530 A upon substitution up-to x = 0.12, afterward this started to decrease from 5.530 to 5.529 A. Pure orthorhombic YFeO3 (o-YFeO3) has cell volume 223.61 (A3), while the cell volume of Pr substituted hexagonal YFeO3 (h-YFeO3) showed a decreasing trend (125.61–125.43 A). Bulk density was thoroughly decreased from 5.009 to 4.634 (g/cm3) by increasing the Pr concentration. Frequency dependence of the dielectric behavior was investigated at room temperature in a comprehensive frequency range of 1 MHz ~ 3 GHz. SEM results exhibited the average grain size 149.28 nm, 66.78 nm, and 69.36 nm for the samples 0.00, 0.08, and 0.16, respectively. The identification of o-YFeO3 was confirmed by two main absorption bands ν1 (449.86 cm-1) and ν2 (567.12 cm-1) and these bands indicate a clear shift upon the addition of Pr. The force constant of absorption bands at tetrahedral and octahedral sites showed increasing trend and this ranges from 1.633dyn/cm2x105 to 1.912dyn/cm2x105 and 2.818dyn/cm2x105 to 8.832dyn/cm2x105, respectively. The substitution of Pr significantly enhanced the dielectric constant. The shifting of peaks at higher frequencies demonstrates that an increase of dopant concentration resulted in the shifting of peaks that may follow the Maxwell-Wagner-Sillars polarization mechanism. Pr substituted YFeO3 exhibited microwave frequency response in a range of 1.6 GHz–2.9 GHz which might be suitable for high-frequency applications.

CuO thin films deposited using SILAR coating technique with various dip-cycles. The prepared thin films were characterized to elucidate the structural and morphological features using analytical techniques such as XRD and SEM, respectively. It was found that along with the thickness of CuO films, the crystallinity and morphology of the deposited films have changed appreciably. The optical, electrical, and photosensing properties were also studied for deposited films. The optical and electrical properties for the thin film prepared with 100 dip-cycles were found best as compared to 50, 75, 125 dip-cycles, this may be due to improved crystallinity and uniform distribution of nanoclusters over the substrate. From the UV absorption studies, it was found that the CuO-100 thin-film has the highest absorption and a low bandgap of 1.67 eV. Also, the CuO with 100 dip sample exhibits a minimum resistivity of 2.98 × 102 Ω cm that leads to a higher carrier concentration of 4.63 × 1013 cm−3 and mobility of 4.53 cm2V−1 s−1. The I–V characteristics of all the deposited CuO samples were investigated and the CuO-100 dip cycle thin film is found to have a lower ideality factor of 5.4. Additionally, the Cu-100 thin film reveals a high responsivity and external quantum efficiency values of 1.67 × 10−1 A/W and 54%, respectively. Thus, in the SILAR dip-coating technique, the dipping cycles influence the CuO formation as well as their properties.

This work investigated the dielectric and optical process of La0.67Ba0.25Ca0.08Mn0.90Ti0.10O3 (LBCMT) manganite using impedance spectroscopy and ellipsometric spectroscopy. LBCMT nano-polycrystalline sample synthesized by the molten salt method was subjected to annealing it 1000 °C. The dielectric performance was estimated on the basis of the polarization of space load relating to the two-layer Maxwell–Wagner’s pattern and the load jump carriers Mn3+ / Mn4+ ions. The frequency-dependent dielectric constant showed normal behavior. The variation of the differential of ANC was found at 400 K in LBCMT. The complex impedance measurements’ inputs showed that the Nyquist plots were adjusted by an appropriate equivalent circuit, implying that both input ascribed to grains and grain boundaries are related to an inductance. Relaxation phenomena of non-Debye type were observed in our ceramic compound, as confirmed by the electrical modulus. Moreover, the frequency related to electrical data was found to obey the law of Jonscher’s. Correlated barrier hoping was determined to be the most appropriate theoretical model to explain the electrical behavior. The activation energies were proved to be

The magnesium oxide (MgO) nanoparticles (NPs) were prepared using the sol–gel method and the prepared nanoparticles were annealed at different temperatures (500, 600, and 700 °C). The prepared nanoparticles were characterized using X-ray diffraction (XRD) for the structural analysis (Rietveld refinement), SEM for surface morphological analysis, and the energy dispersive X-ray analysis for elemental compositional analysis. The detailed structural analyses proved the expansion of the unit cell by increasing the annealing temperature. The detailed electronic bonding behavior and the expansion of the unit cell of the prepared nanoparticles were analyzed and reported using the maximum entropy method (MEM). The light absorption behavior of the MgO was probed using UV–Vis-NIR spectroscopic analysis. The photocatalytic decomposition capabilities of the synthesized MgO nanoparticles were studied against a model pollutant such as methylene blue dye. The maximum photocatalytic efficiency of 92% in 150 min was observed for MgO nanoparticles annealed at 700 °C.

The development of materials in two-dimensions has been established as an effective approach to improve their thermoelectric performance for renewable energy production. In this article, we generated monolayers of the orthorhombic structured lead-chalcogenides PbX (X = S, Se, and Te) for room-temperature thermoelectric applications. The Density functional theory and semiclassical Boltzmann transport theory-based computational approaches have been adopted to carry out this study. The band structures of PbX monolayers exhibited narrow indirect bandgaps with a large density of states corresponding to their bandgap edges. Accordingly, substantial electrical conductivities and Seebeck coefficients have been obtained at moderate level doping that has caused significant thermoelectric power factors (PFs) and figures-of-merit (zT) ~1. The single-layered PbX showed anisotropic dispersion of electronic states in the band structure. A relatively lighter effective mass of charge carriers has been extrapolated from the bands oriented in the y-direction than that of the x-direction. As a result, the electrical conductivities and PFs have been observed larger in the y-direction. The optimum PFs recorded for single-layered PbS, PbSe, and PbTe in y-direction amounts to 9.90 × 1010 W/mK2s at 1.0 eV, 10.40 × 1010 W/mK2s at 0.82 eV, and 10.80 × 1010 W/mK2s 0.66 eV respectively. Moreover, a slight increase in p-type doping is found to improve the x-component of the PF, whereas n-type doping has led to improvement in the y-component of PF. Our results show an improved thermoelectric response of PbX monolayer (PbTe in particular) than their bulk counterparts reported in the literature, which indicates the promise of PbX monolayers for nanoscale thermoelectric applications at room temperature.

We investigate here the effect of holmium on Li–Co nano-ferrites to elaborate the surface morphology, dynamic magnetic and electrical transport properties. The transmission electron microscopy (TEM) technique was employed to examine the microstructure and grain size distribution. TEM analysis confirmed the nanocrystalline nature (~50 nm) of the prepared materials. X-ray photoelectron spectroscopy (XPS) experiment results verify the presence of all metal ions with the required valences. Ferromagnetic resonance (FMR) analysis revealed the need for a dense microstructure to cut down the microwave losses. FMR line width was observed to reduce from 2757 -to 1676 Oe except for x = 0.12 by the substitution of Ho ions which correspond to low microwave losses. The dc resistivity results show that high resistivity values are associated with smaller grains of the samples and vice versa. Resistivity values are found to increase from 3.66 × 108 -to 5.31 × 108 Ω-cm by increasing the Ho addition. Seebeck experiment revealed n-type conduction. Together with showing the nature of charge carriers, a decrease in the Seebeck coefficient with increasing Ho ensured the replacement of Fe ions by Ho ions on B-sites.

In this work, we have coated 0, 1, 3, and 5 wt% of Erbium (Er)-doped tin oxide (SnO2) films on glass using a simple nebulizer spray pyrolysis method to make an ammonia vapor sensor with remarkable sensitivity. X-ray diffraction, Atomic force microscopy, Ultraviolet–visible spectroscopy and photoluminescence methods were employed to inspect the thin-film samples. Room-temperature ammonia vapor sensing was performed by a computer connected to the homemade gas-sensing system. The results obtained show that Er doping in SnO2 films gradually decreased the crystallite size with an increase of the surface area improving the sensing property of the vapor. A minimum optical band gap (i.e., 3.23 eV) is achieved for 5 wt% Er-doped film. The fabricated Er-doped SnO2 gas sensor showed response/recovery time highly dependent on dopant concentration. The Er concentration of 5 wt% doped SnO2 thin film showed maximum sensitivity of 91%, fast response, and recovery time of 29 and 7 s, respectively, due to high surface to volume ratio.

The structural, magnetic, and electrical properties were analyzed to see the impact of yttrium ions upon manganese spinel ferrite. The samples of MnYyFe2-yO4 (y = 0-0.1) were created by wet chemical sol–gel method. The development of cubic spinel configuration was observed in all models with the use of X-ray diffraction analysis. The values of different magnetic parameters like saturation magnetization and remanence declined with the increase of yttrium concentration, while coercivity was enhanced. The real and imaginary parts of permittivity decreased with the increase in Y concentration. The impedance enhanced with the substitution of Y3+ ions. The M-H loops of all the samples were experimentally measured from − 2 K Oe to + 2 KOe. All these parameters suggested that manganese-based ferrites may be used in microwave absorption.

Silver-coated ZrO2 and individual ZrO2 nanoparticles have been synthesized using the simple reduction and co-precipitation methods, respectively. The synthesized products were examined using the X-ray diffraction, energy-dispersive X-ray and UV–visible spectroscopy, which confirmed the successful synthesis of materials. Scanning electron microscopy and transmission electron microscopy revealed the round-shaped nanoparticles of both materials. The cyclic voltammograms revealed the well-defined redox peaks and recommended the pseudocapacitive nature of the electrodes. The silver-coated zirconia showed higher specific capacitance of 792 F/g at 10 mV/s as compared to individual zirconia (10.22 F/g). Silver-coated ZrO2 also showed good power density of 274.5 W/kg at current density of 5 mA/cm2 through the galvanostatic charge discharge profile. Hence, the results suggest that silver-coated ZrO2 showed improved electrochemical performance as compared individual ZrO2 due to higher electrical conductivity and specific surface area. Hence, silvercoated ZrO2 nanoparticles can be employed as an electrode material for supercapacitor applications.

The dielectric properties of pure and yttrium-doped PbS nanoparticles synthesized by the coprecipitation chemical synthesis route have been studied by several characterizations. X-ray diffraction patterns of samples were employed to estimate the crystallite sizes and intrinsic microstrains using Williamson–Hall (W–H) plot analysis. The crystallite size and intrinsic macrostrain values were evaluated in the range of 13.7–15.9 nm and 1.09 × 10–3–1.72 × 10–3, respectively, using W–H plots. The formation of nanoparticles, nanoflakes, sponge, and nanosheets were seen via scanning electron microscope (SEM). Energy dispersive spectroscopy (EDS) of 5.0 wt% confirms the Y: PbS sample elements' chemical composition and stoichiometry. The optical band gaps increase in the range of (0.93–1.17 eV) with an increase in the dislocation density. The higher values of dielectric constant (23.6–28.0), dielectric loss (37.6–176.8), loss tangent (2.7–8.6), and electrical conductivity [ 10.2 to ( 11.7) S/m] have been reported at the lower frequency. The highest electrical conductivity values were obtained in the range of [ 4.71 to ( 4.81) S/m] for as-prepared samples. The greater capacitance and impedance values were found at 3 kHz and decrease with increasing the frequency up to 10 MHz. The current–voltage characteristic curves of undoped and Y: PbS NPs were performed under biased voltage. The space charge current density was noticed in the range of (8.7 × 10–4–4.2 × 10–4 amp/cm2) at 1.0, 2.5, and 5.0 wt% of Y: PbS samples. The enhancement in the optical band gap and dielectric and electric properties on yttrium doping in PbS compared to pristine PbS NPs makes them suitable for optoelectronic applications.

The atomically thin two-dimensional (2D) materials have received remarkable attention for their promising applications in cutting-edge technological applications. In this article, we devised square and hexagonal shaped monolayers from the 110-facet and 011-facet of β-BeO type structured ZnO by separating them from the adjacent layers by a distance of 20 A. The energetic stability, lattice parameters, electronic and optical properties of these monolayers have been examined comprehensively using the density functional theory. In pursuit of this study, the wurtzite structured ZnO (w-ZnO) is first transformed into the β-BeO structure by applying a negative pressure of −5.4 GPa. The obtained monolayers exhibited comparable cohesive and formation energy to that of w-ZnO. The electronic structure calculations performed with the Tran-Blaha modified Becke Johnson exchange potential, demonstrated the 110-monolayer as indirect bandgap and 011-monolayer as direct bandgap semiconductors having bandgaps 1.59 eV and 1.72 eV respectively. The 110-monolayer exhibited isotropic optical coefficients whereas considerable anisotropy has been recorded in the dispersion of optical spectra of 011-monolayer. Also, these monolayers exhibited thermally stable excitons of binding energies estimated as 3.32 eV for 110-monolayer and 1.53 eV along the x-axis and 1.19 eV along the y-axis for 011-monolayer. Investigations of the refractive indices indicated both monolayers as of transparent nature. Our study provides the pathways to serve as a useful reference for designing low-cost and nontoxic 2D polymorphs of ZnO for optoelectronic applications in miniaturized portable devices.

The new perovskite compound La0.7Sr0.3Mn0.8Fe0.2O3 (LSMFO) was synthesized via the solid-state reaction process. The structural properties of LSMFO were measured at room temperature using Scanning Electron Microscopy and powder X-ray pattern. Our sample crystallized in the rhombohedral ( $$R\overline{3} c$$ ) structure. The electrical and dielectric behaviors were investigated by complex impedance (CI) spectroscopy. The results indicated the existence of an electrical relaxation process in LSMFO. Moreover, the frequency related to the ac-conductivity result was determined by Jonscher's universal law and the Correlated Barrier Hoping was the most appropriate theoretical mechanism to elucidate the electrical conduction process. The dielectric studies revealed that the dielectric relaxation was monitored by the dc electrical mechanism. The dielectric properties showed a high permittivity, which supports the potential use of LSMFO in electronic devices.

The different contents (0 wt.%, 1 wt.%, 3 wt.% and 5 wt.%) of Nd @CdS films were casted using spray pyrolysis deposition procedure. The preferential orientation of crystallites along (002) for all films was noted by XRD profiles. The mean crystalline size (Davg), strain (ɛavg) and dislocation density (δavg) have also been evaluated using XRD results and discussed. The spherical shape morphology of nanoscale particles of Nd@CdS films were analyzed by FE-SEM, exhibits the increased grain sizes with Nd doping concentration. The optical band gaps (2.4–2.36 eV) were found to be decreased with increasing Nd doping content upto (3 wt.%) and increased at 5 wt.% The PL profile displays a stout intensity peak observed at 532 nm and week emission band at 638 nm. The dielectric constant, loss and loss tangent of pristine and Nd@CdS thin films were investigated by dielectric measurements. The optimum values of non-linear refractive index 1.06 × 10−10, 4.41 × 10−11, 3.44 × 10−11 and 1.85 × 10−10 were observed for Nd content varies from pristine to 5 wt.% respectively. Furthermore, optimum non-linear susceptibility values 7.31 × 10−12, 1.079 × 10−12, 4.53 × 10−13 and 1.36 × 10−11 were observed for 0, 1, 3 and 5 wt.% of Nd contents respectively in CdS. Such type of characteristics of Nd doped CdS thin films can be useful for optical devices.