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Ferroelectric HfO2-based materials hold great potential for widespread integration of ferroelectricity into modern electronics due to their robust ferroelectric properties at the nanoscale and compatibility with the existing Si technology. Earlier work indicated that the nanometer crystal grain size was crucial for stabilization of the ferroelectric phase of hafnia. This constraint caused high density of unavoidable structural defects of the HfO2-based ferroelectrics, obscuring the intrinsic ferroelectricity inherited from the crystal space group of bulk HfO2. Here, we demonstrate the intrinsic ferroelectricity in Y-doped HfO2 films of high crystallinity. Contrary to the common expectation, we show that in the 5% Y-doped HfO2 epitaxial thin films, high crystallinity enhances the spontaneous polarization up to a record-high 50 µC/cm2 value at room temperature. The high spontaneous polarization persists at reduced temperature, with polarization values consistent with our theoretical predictions, indicating the dominant contribution from the intrinsic ferroelectricity. The crystal structure of these films reveals the Pca21 orthorhombic phase with a small rhombohedral distortion, underlining the role of the anisotropic stress and strain. These results open a pathway to controlling the intrinsic ferroelectricity in the HfO2-based materials and optimizing their performance in applications.

GaN1−xZnOx solid solution has emerged as a promising candidate to generate clean and sustainable hydrogen energy. We revisit the electronic structure properties of ZnO-GaN systems using an evolutionary algorithm designed for crystal structure prediction coupled with ab initio calculations. An orthorhombic GaN-ZnO crystal phase, with space group Pmc21 (no. 26), was uncovered. The thermodynamic stability analysis reveals that while the Pmc21 crystal is not stable against phase separation, GaN-ZnO has low formation enthalpy of ~30 meV/atom and a relatively moderate miscibility temperature of ~461°C. The calculated phonon structure shows that GaZnNO is dynamically stable. The derived direct bandgap (Γ→Γ) value of 1.875 eV could be exploited in solar cell applications, providing high efficiency of ~25% for a thickness of ~0.5 μm based on the metric of spectroscopic limited maximum efficiency. The valence band maximum at the Γ point shows strong antibonding Zn(d)-N(p) character. The Zn(d)-N(p) repulsion mechanism reduces the direct band by almost ~2 eV. Moreover, we find a huge optical bandgap bowing of 6.3 eV. Our calculations indicate that atomic displacements induce dynamical charges of large amplitude and are the key factors favoring strong bandgap variation and extreme bandgap bowing parameters.

Layered perovskite structured Re5Ti4CrO17 (Re = La, Nd) ceramics were synthesized via a sol–gel method. Rietveld analysis and Raman spectroscopy showed that the samples crystallize into an orthorhombic crystal structure with the space group Pmnn. The samples showed a dense and homogeneous microstructure when sintered at 1600 °C for 4 h and the grain size was found to be 2.64–4.93 μm. La5Ti4CrO17 and Nd5Ti4CrO17 exhibited dielectric constant (er) ~ 23 and 12 at 1 MHz, respectively, which was dependent on the dielectric polarizability and bond lengths. Dielectric loss at room temperature was found to be ≤ 0.05 (at 1 MHz) for La5Ti4CrO17 and Nd5Ti4CrO17, respectively. Furthermore, magnetic study of the samples showed a paramagnetic behavior.

Different phases of tungsten trioxide (WO3) nanoparticles were synthesised by hydrothermal method involving the extracts of avverhoea bilimbi, citrus limon and tamarindus indica as capping agents. These synthesized nanomaterials were characterized through X-ray diffraction, Raman spectra, Transmission electron micrographs, diffuse reflectance spectra and photoluminescence spectral techniques. The X-ray diffraction patterns and Raman spectra corroborate the formation of different crystal phases viz., monoclinic (m-WO3), orthorhombic (o-WO3) and hexagonal (h-WO3). The morphological and topographical studies were acquired from SEM and TEM images. The surface parameters were examined from BET isotherms. The absorption spectra reveal that the optical band gap energy is found to be higher for h-WO3. The adsorption of Cu(II) ions were found to be effective provided with optimum conditions and the adsorption capacity was found to be 174.5 mgg−1 by the h-WO3 nanoparticles. A study on Langmuir, Freundlich, D–R and Temkin isotherm models, deviation in D–R model implies that the adsorption is chemisorption process and follows pseudo-second order kinetics. The adsorption process is found to be spontaneous and exothermic from the thermodynamic parameters.

For the investigation of the exchange bias effect and magneto-optical properties of Bi0.8Re0.2(Re = Nd and Sm)FeO3 (BNFO and BSFO) nanofibers were synthesized via the electrospinning technique. The crystal structure was changed from rhombohedral phases of space group R3c before undoping shift to orthorhombic phases of space group Pbam and Pnma after doping of Nd3+ and Sm3+ ions, respectively, by the Rietveld refinement results. Analysis of the magnetic hysteresis loops demonstrated that the remanent magnetization especially coercivity of BNFO and BSFO nanofibers at 10 K and 300 K exhibited obviously variation, which was attributed to the lower temperature suppressed the fluctuation of magneto-caloric and valence state. The XPS and EDS results displayed the Nd3+ and Sm3+ ions were successfully doped into BFO nanofibers. Meanwhile, the lattice distortion induced the suppression of antiferromagnetic ordered spin modulation, which played an important role to enhance the magnetic properties. It was observed that the exchange bias effect (HEB) of BNFO nanofibers was higher than those of BSFO nanofibers. UV–vis spectra measurements revealed the band gap of BNFO and BSFO nanofibers was 1.87 eV and 1.85 eV, respectively, and the absorption edges of BSFO nanofibers occurred a slightly red shift. The MO degradation rates of BNFO and BSFO nanofibers reached about 89.4% and 78.6%, respectively, which could be a potential candidate in photo-electron devices and the semiconductor industry.

In this work, Li2Mg2[WxMo(1−x)O4]3 (i.e., 0 ≤ x ≤ 1) ceramics with high Q×f values were successfully fabricated at low temperatures (i.e., ≤ 950°C). The sintered specimens were found to exhibit of a single orthorhombic phase when x ≤ 0.6, whereas a secondary phase of MgWO4 was detected in the specimens when x ≥ 0.8. The ceramic samples exhibited homogenous microstructures and relatively high densities (i.e., > 90%) . In the sample with x = 0.2, outstanding microwave dielectric properties of er = 8.05, Q×f = 50,780 GHz, and τf = −73.6 ppm/°C were achieved at the sintering temperature of 825°C. Furthermore, no apparent reaction between a Ag electrode and the ceramic matrix was observed during the sintering process. As a result, Li2Mg2[WxMo(1−x)O4]3 ceramics proved to be promising candidate materials for low temperature co-fired ceramic (LTCC) technology.

The effects of a uniform and biaxial strain on the electronic structure of wide-bandgap orthorhombic Ga2O3 are studied using density-functional theory with the generalized gradient approximation (GGA) and the meta-GGA. Under uniform strain, as the strain increases, the lattice constants of the system decrease and the bandgap increases. However, under epitaxial strain, the bandgap increases with increasing compressive strain up to a certain level, and further increasing the compressive strain decreases the bandgap. This phenomenon is closely related to Poisson's ratio and increases of the lattice constant along the c-axis, which is not constrained by the epitaxial strain.

Thermally and chemically stable perovskite-like layer structures have attracted extensively in the field of energy and environmental applications. In this study, La2Ti2O7 was synthesized by the solvothermal method at 180 °C. This method provides high pure and homogeneously dispersed nanorods of orthorhombic phase having length of 250 nm and width of 70 nm. Even though this is a low-temperature synthesis method, it yields high crystalline nature after calcination. The novelty of this work is its synthesis methodology by the solvothermal route to achieve lower weight loss of La2Ti2O7. Furthermore, they exhibit narrow absorption in the UV-region from 200 to 350 nm, makes it possible to fabricate it as UV photodetector at ambient condition. In presence of UV illumination at 390 nm, it shows sharp photocurrent response with the decay time of 1.7 s.

0.675BiFeO3-0.3BaTiO3-0.025LaFeO3-x mol% Nb2O5 (x = 0–1.25) multiferroic lead- free ceramics, fabricated by conventional solid-state reaction, were studied to reveal the effects of Nb2O5 on the structural, morphology, dielectric, ferroelectric, magnetic and magnetoelectric properties of the BiFeO3-based ceramics. After the addition of Nb2O5, the crystal structure of as-prepared samples remained orthorhombic phase. The doping Nb5+ ion could be able to inhibit grain growth remarkably and suppress the creation of oxygen vacancies of this ceramics, which resulted in the improvement of electrical insulation by two orders of magnitude. The ferromagnetism was apparently enhanced with increasing content of Nb2O5, and the observed remanent magnetization Mr peaked at 0.022 emu/g for x = 1. Suitable amount of Nb2O5 could be beneficial to the dielectric properties, with the optimal x at 0.75, with dielectric constant er of 918 at 100 Hz. The observed magnetoelectric coefficient αME suggested the existence of magnetoelectric coupling effect in these ceramics. The αME value almost decreased after adding Nb2O5, possibly due to the obvious degradation of ferroelectric behaviors.

0–5% Pd-doped Bi2MoO6 nanoplates as visible-light-driven photocatalysts were successfully prepared in this research. The XRD patterns of as-prepared Pd-doped Bi2MoO6 samples were indexed to pure orthorhombic Bi2MoO6 phase with no impurity detection. The Raman and FTIR wavenumbers of Pd-doped Bi2MoO6 nanoplates were significantly shifted by the change of energy bonds in Bi2MoO6 nanoplates, including the TEM characterization of the growth of nanoplates through the exposure {020} facet. Main symmetric stretching vibration of MoO6 containing in Pd-doped Bi2MoO6 nanoplates were also detected. XPS of 3% Pd-doped Bi2MoO6 nanoplates revealed the binding energies of Pd 3d5/2 and Pd 3d3/2 core levels, which are indicative of incorporated Pd2+ ions in Bi2MoO6 lattice. The photocatalytic activities of Bi2MoO6 with and without being loaded with Pd dopant monitored through the degradation of rhodamine B were increased from 38.36% for Bi2MoO6 to 97.12% for 3% Pd-doped Bi2MoO6 photodegraded by h+ and ·O2− main active radicals. The 3% Pd-doped Bi2MoO6 nanoplates were very stable and reusable for wastewater treatment.

(Cu0.5Tl0.5)(Ba2–yCay)(CaMg)(Cu3–xZnx)O10–δ (y = 0, 1; x = 0, 2, 2.5, 2.8, 3) and (MxTl1–x)(BaCa)(CaMg) Zn3O10–δ (M = Ag, K; x = 0, 0.5) superconductors are synthesized for the studies of role of spin density waves in the mechanism of high Tc superconductivity. Such compounds are synthesized by reducing the thickness of the charge reservoir layers and distance among various CuO2/ZnO2 planes; decreasing the thickness of charge reservoir layers (CRLs) and distance among the various CuO2/ZnO2 planes increase the spin–spin interaction. All such samples were prepared by a two-step solid-state reaction (SSR) method at 860 °C and have shown orthorhombic crystal structure in which volume (V) of the unit cell suppresses with the doping of Ca, showing that partial substitution of Ca at the Ba site suppresses the thickness of CRL that in turn promotes a decrease in c-axis length and volume of the unit cell. The phonon modes related to the vibrations of apical and planar oxygen atoms are softened with doping of Ca and Zn in the final compounds. Metallic variations of resistivity (ρ) from room temperature down to the onset of superconductivity are a typical feature of these samples in which the Tc(onset) and Tc(R = 0) suppress with the doping of Ca, Mg, and Zn in the final compounds. Surprisingly, the samples with all the CuO2 planes replaced by ZnO2 planes have shown superconducting properties. To confirm the role of Cu(3d9) atoms in superconductivity, we have synthesized (MxTl1–x)(BaCa)(CaMg) Zn3O10–δ (M = Ag, K; x = 0, 0.5) samples. To our surprise, such samples have shown semiconducting behavior and no sign of superconductivity down to 77 K which demonstrated that the presence of Cu(3d9) atoms either in CRLs or ZnO2 planes is essential for the mechanism of high Tc superconductivity. These studies have shown the unequivocal role of small spin-carrying Cu-atoms in the mechanism of high Tc superconductivity. Fluctuating spins of Cu(3d9) atoms in the CuO2 plane generate spin waves, and hence, their interaction with charge density waves develop long-range phase coherence among the carriers that result in high-temperature superconductivity in oxides.

This manuscript is discussing the growth of a new class semi-organic nonlinear crystal l-Lysine hydrogen chloride (LLHC) was grown by slow evaporation method using a mixed solvent of deionized water + ethanol and pure deionized water. The crystal crystallizes in orthorhombic space group of P212121. Lattice parameters were revealed by single crystal X-ray diffraction analysis. The FT-IR spectral analysis was performed on the grown crystal LLHC to identify its functional groups. The position of protons and carbons was determined by the NMR technique. The grown crystal was characterized by optical transparency through UV–Vis range with a short cutoff wavelength of 212nm. Thermal and physiochemical stability of the title crystal was found out through the TG-DTA analysis, which proves the crystal stability up to 251.4 °C. Brewster’s point method was used to find out the refractive index of the grown compound LLHC. Vickers’s microhardness test was performed on LLHC to find out its mechanical stability. The second harmonic generation (SHG) of the grown crystal LLHC was confirmed by the Kurtz-perry powder method and the SHG efficiency was compared with the known Potassium Dihydrogen phosphate (KDP) standard. By using a minimal bactericidal concentration (MBC) benchmark, their antibacterial activity was evaluated. The grown crystal shows long-term and outstanding antibacterial activity against E.coli and S.aureus.

Highly electroactive Zn-embedded Ni9S8 nanosphere and its ZnS/NixS6-based nanocomposites were prepared by a simple hydrothermal route. The prepared samples were characterized by X-ray diffraction (XRD), Fourier transformed infrared spectra (FTIR), high-resolution scanning electron microscope (HR-SEM), transmission electron microscope (TEM), energy-dispersive X-ray spectral (EDX) techniques. The XRD analysis revealed the formation of orthorhombic phase of Zn-embedded Ni9S8 nanosphere for hydrothermally treated sample. The supercapacitance behavior of crystalline Zn-embedded Ni9S8 nanosphere and ZnS/NixS6 nanocomposite modified electrodes were investigated using electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV) and galvanostatic charge-discharge (GCD) techniques. Zn-embedded Ni9S8 nanosphere prepared by hydrothermal route achieved highest specific capacitance value of 145 F/g in 1 A/g compared to the calcined sample modified electrodes. The maximum capacity retention of 100, 96 and 90% at 2000 cycles @1 A/g were observed for the pristine Zn–Ni9S8 and calcined Zn-Ni9S8 at 200 and 300 °C, respectively.

The detailed comparison of the effects of Co and CoFe2O4 dopants and preparation methods (solid-state reaction method and sol–gel methods) have been studied on structural, electrical, superconducting, and mechanical properties of Y123 bulk superconductors. The doping amounts of Co and CoFe2O4 were chosen up to 0.10 wt. %. X-ray powder diffraction (XRD) method, temperature-dependent resistance measurement (R-T), and Vickers microhardness analyses were performed to characterize prepared samples. XRD analysis showed that all samples have Pmmm symmetry of orthorhombic crystal structure; intensities and width of the diffraction lines were affected by doping material, but, independent of the preparation method. Although all samples crystallize in orthorhombic structure and exhibit superconductivity behavior, with increasing doping rate the critical transition temperatures of the samples showed a significant decrease and broadened to superconducting temperature transition width. This is more evident in CoFe2O4-doped Y-123 samples produced by sol–gel method. As the applied force increased, it was observed that the microhardness values of the Co-doped samples increased while the CoFe2O4-doped samples decreased, regardless of the sample preparation method.

The crystal and electronic structure properties of Ni-B (nickel-boron) alloy coatings produced by an electrodeposition method have been investigated. The crystal structures of the alloy coatings were determined by x-ray diffraction patterns and supported by extended x-ray absorption fine structure (EXAFS) spectroscopy. The local atomic structure around the Ni atom was obtained from EXAFS studies at the Ni K-edge, and the EXAFS data were fitted with theoretical calculations. With the addition of boron atoms in the nickel environment, NiB composite alloys were formed in the crystals with an orthorhombic "Cmcm" structure. The analysis revealed a limited effect of boron doping in the electronic structure of the nickel atoms. Boron atoms were determined as sitting between the Ni atoms and causing a disturbance in the crystal structure due to providing inhomogeneous interstitial potential and defects.

High-performance alloy materials are increasingly considered for various engineering applications due to their combination of desirable properties. However, the guided wave-based structural health monitoring of alloys is often challenged by their strong anisotropic nature, which makes it difficult to calculate the guided wave behavior and associate mode shapes. In this article, Lamb mode waves of Cu–Al–Ni alloy under uniaxial stresses are characterized by developing a novel numerical polynomial approach, which may provide an efficient way to solve problems concerning acoustic wave propagations. To facilitate understanding of the dispersion curve trajectories, the anisotropic phase transformation from cubic phase (austenite) to orthorhombic plate (martensite) is considered. The comparison of the evanescent mode trajectories between the cubic and orthorhombic alloys shows the presence of imaginary modes in the cubic phase, although they may not exist in the orthorhombic phase at specific frequencies. In the case of Lamb propagation in the cubic alloy, the dispersion curves oscillate strongly, creating crossings among multiple symmetric and antisymmetric modes. This study also concerns the second harmonic generation of Lamb mode pairs in cubic and orthorhombic alloys. Furthermore, effect of uniaxial stresses on Lamb dispersion curves in both phases are also identified and discussed. The results obtained may promote understanding and optimization of novel acoustic devices made of anisotropic materials.

α -vanadium pentoxide (α-V2O5) thin films with the orthorhombic crystal structure were successfully grown on Si-substrates using pulsed laser deposition (PLD) technique with varying substrate temperatures. XRD spectra confirm the formation of orthorhombic V2O5 phase which is evident as the strongest peak at ~ 20.38°. The films are apparently crystalline in nature, and the average crystallite size ranges between ~ 200 nm–~ 400 as obtained from Scherrer’s equation. FESEM image shows the films as compact nanostructured type displaying a globular (at 500 °C) or sheath like morphology (at 600 °C and 700 °C). AFM study shows that the average surface roughness of V2O5 films increases with increasing substrate temperature. UV–vis spectroscopy shows that the fundamental absorption edge has shifted to the red side (higher wavelength) with increasing temperature. Optical band gap values (Eg) decrease with increasing deposition temperature (at 700 °C, Eg ~ 2.08 eV).

Eleven examples of hexagonal and orthorhombic polymorphs of intermetallic compounds having 5:3 stoichiometry are listed in the International Crystal Structure Database. A transition temperature between them has only been determined for the Yb–Sb and Sr–Bi systems, but results on the Sr–Bi system are discrepant with those on the Yb–Sb system, in which the phase relationships are well constrained by experimental data, for example, that the lower-temperature polymorph is the prototype orthorhombic Yb5Sb3 structure (αY5Sb3) and the higher temperature polymorph (βYb5Sb3) is isostructural with hexagonal Mn5Si3, with the transformation occurring at 1280 °C. In contrast, thermodynamic modeling on the Sr–Bi system give the inverse sequence of polymorphs with increasing temperature. It appears unlikely that the hexagonal Mn5Si3 structure type can be stable at higher temperatures than the orthorhombic Yb5Sb3 structure in one system, while orthorhombic Yb5Sb3 structure is the stable phase at higher temperatures in another system. The discrepancy can be attributed to the limited experimental data used to model the phase relationships in the Sr–Bi system.

The present article is focused to probe guanidinium benzene-1,2-dicarboxylate (GUBD) crystal synthesized by slow evaporation technique. The synthesized material possesses centrosymmetric structure with Pbcn space group having orthorhombic crystal system. The inter-contacts of the synthesized material have been investigated using Hirshfeld surface analysis and it clearly visualizes that the intermolecular hydrogen bonding takes place for structural stabilization. The functional groups of synthesized material have been affirmed from FT-IR and FT-Raman spectra. GUBD possess cut-off edge at 250 and 272 nm with high optical transparency in the visible-NIR region. The T/G and DTA show studied compound is thermally stable up to 300 °C. The observation of maximum intensity peak for the GUBD crystal at 570 nm pointed out green fluorescence emission. The Vicker’s hardness analysis reveals reverse indentation size effect. Dielectric studies of the GUBD crystal were measured. The nonlinear optical measurements on GUBD material confirm the two-photon absorption with reverse saturable absorption behavior and the crystal is potentially sufficient for optical limiting-based laser safety devices. The antibacterial activities of GUBD crystal against strains Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus have been analyzed. Furthermore, the grown GUBD crystal finds potential application in the field of electro-optic device and pharmaceutical applications.

Perovskite structured materials have received a lot of attention recently due to their extraordinary characteristics. In this work, conventional solid-state reaction was adopted to synthesize perovskite-based lanthanum ferrite materials and studied their inherent properties with the influence of Mn concentrations. The materials were characterized by XRD, FTIR, Raman, SEM, EDS and mapping, UV–Vis, photoluminescence, dielectric, magnetic properties and the Mn ions were found to be incorporated into the lanthanum ferrite. Rietveld refinement results confirm that synthesized materials are single-phase orthorhombic structures with an average crystallite size of 80–67 nm. A broad excitation band around 360 to 450 nm with a maximum at 409 nm is attributed to the intra configurational f–f electronic transition of La3+. Mn-doping-induced great enhancement in the visible range of LaFeO3 red luminescence. Mn-dopant has a significant influence on dielectric characteristics in the frequency ranges of 1 kHz and 1 MHz from 50 to 110 °C, which obey the Maxwell–Wagner polarization model and Koop's phenomenological theory. The observation of weak ferromagnetism at 305 K in the M–H loop is considered to be the result of the intriguing exchange interaction between Fe/Mn and oxidation states. It is proposed that LaMnxFe1−xO3 (x = 0.05–0.25) materials with varying characteristics could be developed to satisfy a diversity of requirements.

In this work, we report the sol–gel spin-coated novel thin film Aurivillius Phase Layered Bismuth titanate (Bi4Ti3O12, BTO) thin film coated on FTO glass substrate annealed at 700 °C was prepared and its detection of mercury ion. The structural orientation, surface morphology, chemical composition, vibrational, and optical properties of the prepared thin film were characterized using XRD, SEM, XPS, Raman, UV–Vis, and PL, respectively. From the XRD analysis, the crystal growth is well preferred in (117) plane corresponding to the orthorhombic structure of BTO. SEM images of the prepared thin film exhibited an anisotropic plate-like grained structure. Photoluminescence spectra showed a good optical emission peak at 545 nm. In Raman spectra, the observed phonon modes are well correlated to the orthorhombic phase of BTO thin films. XPS confirmed the oxidation states of Bi4Ti3O12 thin film. The electrocatalytic activity of the prepared BTO thin film electrode concerns mercury detection using cyclic voltammetry (CV) and linear sweep voltammetry (LSV) technique. CV analysis disclosed that the prepared thin film electrode is very active in the electrochemical performance of heavy metal (Hg) detection. LSV result reveals that the prepared thin film exhibits enhanced sensitivity and lower detection limit of electrochemical Hg detection. From the electro-oxidation studies, the BTO thin film electrode acts as a favorable candidate for the application of heavy metal detection.

International audience; A new salt Bis(o-xylylenediammonium) tetrachloride monohydrate, denoted by OXDACl, produces a novel organic-inorganic compound with centrosymmetric property, prepared by slow evaporation technique in an aqueous solution. This one has been assumed a pattern in the orthorhombic Pnma space group, and the following crystallographic parameters obtained are a = 9.0677(9) angstrom, b = 24.282 (2) angstrom, c = 9.4726 (8) angstrom, V = 2085.7 (3)angstrom(3) and Z = 4, at 150 K. It is investigated by X-ray diffraction, fluorescence, infrared, and UV-visible spectroscopy. The crystal wrap is endorsed by the O-H center dot center dot center dot Cl, N-H center dot center dot center dot Cl hydrogen bond interactions among the organic network and the inorganic one, which stabilize the crystal packing. Besides to get a perception into the attitude of these interconnections, Hirshfeld surfaces analysis have been scrutinized. Computational calculations were performed, employing density functional theory (DFT), and were made by comparison with the experimentally determined structure to examine the molecular structure with geometrical optimization, vibrational, and topological parameters of OXDACl by B3LYP/6-311 + + G(d,p) basis.

A novel nonlinear semiorganic optical single crystalline material, anilinium hydrogen sulfate (AHS), was blended via slow vaporization process. The AHS crystal morphology was predicted to fling light on the development rate and to reveal the prominent facets. The AHS belongs to orthorhombic crystal structure and has Pca21 non-centrosymmetric space group. The energy gap, global reactivity descriptors, linear and nonlinear optical (NLO) specifications of AHS at molecular base were calculated at B3LYP/6-31G (d,p) level. The mechanical, optical and thermal tests performed on AHS crystal showed superior properties and its suitability for NLO device applications. In addition, the studies revealed that the AHS crystal is having phase matching behavior.

Effects of Ga substitutions in R2Al1-xGax (R = Gd, Er) alloys have been studied. Gd2Al1-xGax (x ≤ 0.2) and Er2Al1-yGay (y ≤ 0.3) alloys are found to be crystallized in Co2Si-type orthorhombic structure. With increased Ga substitution for Al, the phase transition temperature is gradually increased. For the field change of 7 T, the maximum of entropy change (-ΔSM) is increased to 14.8 J/kgK and 11.2 J/kgK in Gd2Al0.8Ga0.2 and Er2Al0.7Ga0.3 alloys compared with 11.4 J/kgK and 8.3 J/kgK of Gd2Al and Er2Al alloys. And the relative cooling power is nearly doubled to 699.6 J/kg in Gd2Al0.8Ga0.2 alloy. As increasing Ga substitution, the critical magnetic field for the transition is decreased in Gd2Al1-xGax (x ≤ 0.2) alloys, and the magnetization is increased in Er2Al1-yGay (y ≤ 0.3) alloys. The considerable ΔSM implies that those materials are promising candidates for magnetic cooling.

High-quality nanometric and homogeneous particles of Cu–doped PrCrO3 ceramic compounds were synthesized by the hydrothermal-assisted sol–gel method. Structural, chemical state, morphology, and magnetic properties were investigated in the PrCr1−xCuxO3 orthochromite with 0 ≤ x ≤ 0.1 composition. XRD patterns show a complete solubility of the Cu ion, as well as an increase of the orthorhombic cell volume. The microstructural analysis (SEM) shows that the nanometric-size particles obtained from the synthesis process coalesce during the subsequent high-temperature process. In addition, XPS analysis revealed that the solubility and charge compensations by aliovalent Cu2+ ions substitution are driven by the change of the oxidation state from Cr3+ to Cr5+ and Cr6+. These results produce novel changes in the magnetic properties. There, the ZFC-mode shows negative magnetization in all investigated samples, and it is discussed as an intrinsic phenomenon in terms of the Γ2 (Fx, Cy, Gz) spin configuration as well as the arising of the diamagnetic Cr6+ (do). It is noted that Cr6+ tunes the diamagnetic magnitude during the ZFC protocol. On the other hand, different oxidation states are observed at the Cr site in PrCrO3, whose final result is an increase of the coercivity field, Hc, and the remanent magnetization, Mr, in the M–H curves. The increase of ferromagnetic and the antiferromagnetic domains sharing the same volume leads to an anisotropic magnetic interaction, called exchange-bias effect. It is observed that the Cu-doped PrCrO3 decreases the exchange-bias effect, but at the same time an increase in the magnetic properties is observed at 2 K.

This paper presents the results of a study of the structural, optical, and photocatalytic properties of ceramics based on ATiO3 titanates, A = Ca, Sr, Ba. Using the method of X-ray phase analysis, it was found that in the case of ceramics obtained from a mixture of BaCO3 and TiO2 after annealing, the structure is a mixture of two phases, rhombohedral BaTiO3 and impurity orthorhombic BaTi4O9. In the case of ceramics obtained from a mixture of CaCO3 and TiO2, the structure is a mixture of two phases of the orthorhombic phase and rutile TiO2. In the case of ceramics obtained from a mixture of SrCO3 and TiO2, the structure is a mixture of two phases of the SrTiO3 orthorhombic phase and the Ti2O5 orthorhombic phase. At the same time, all synthesized ceramics have a high crystallinity degree and order of the crystal structure. An analysis of the optical properties showed that the main changes are associated with the difference in the band gap, which is due to the presence of different phases in the structure of ceramics. Based on the results of photocatalytic reactions, the order of photocatalytic activity of the synthesized ceramics was determined: SrTO3/T2O5 > CaTO3/TO2 > BaTO3.

To study the cyclopentane sorption sites and the effect of sorption on the H-ZSM-5 structure, crystal of H-ZSM-5 were prepared by burning out the tetrapropylammonium cations in air. For the adsorption of cyclopentane into H-ZSM-5 crystal, the crystal was treated with zeolitically dried cyclopentane for 6 h at 297 K, and then evacuated for 600 s at this temperature and 1.1 × 10–4 Pa. The structure of a single crystal of cyclopentane sorption complex of dehydrated H-ZSM-5 (MFI, |H3.8(C5H10)1.47|[Al3.8Si92.2O192]-MFI, Si/Al = 24) has been determined crystallographically using synchrotron X-radiation in the orthorhombic space group Pnma; a = 20.141(4), b = 19.944(4), c = 13.439(3) A. It was refined using all intensities to the final error indice R1 = 0.072. The 1.47 cyclopentane molecules per unit cell are located between 5-rings in zigzag channel. The cyclopentane molecules are located perpendicular to the 10-rings of zigzag channel and parallel to the 5-rings of H-ZSM-5 framework at the center of them. Each cyclopentane molecule is held in place by 16 hydrogen bonds between all hydrogen atoms of cyclopentane and framework oxygen atoms of its 5- and 10-rings: C···O ca. 3.318 ~ 3.992 A.

Because of their particular characteristics, searching for potential sp2–sp3 hybridized carbon allotropes has become the foundation of new functional materials in the future. Here, we design a novel carbon phase constructed by sp2–sp3 hybridized bonding networks with a 36-atom body-centered orthorhombic unit cell, termed oC36. oC36 shows thermodynamic stability comparable to most of the theoretically predicted sp3 carbons. The elastic and dynamical stability of oC36 is confirmed by the calculation results of elastic constants and phonon spectra. Analysis of electronic properties reveals that oC36 changes from semiconductivity to one-dimensional conductivity with external pressure exceeding approximately 4 GPa. The conductivity arises from the overlap of the valance and conduction bands owing to sp2 hybridized nonbonding carbon interactions as the lattice constant decreases. Electron–phonon coupling calculations indicate the superconductivity of oC36 under 25 GPa, and its λ and TC values are 0.50 and 10.7 K, respectively. Strikingly, the estimated hardness, tensile strength, and shear strength of oC36 reach remarkably high values of 69.5, 79.1, and 78.9 GPa, respectively, indicating its superhardness and ultra-incompressibility. Our research expands the scope of sp2–sp3 carbon allotropes and provides new ideas for the later theoretical design of carbon allotropes with switchable properties.

Fayalite Fe2SiO4 is synthesized by the solid-state reaction without ball milling. The obtained powder is further structurally and electrochemically examined. Field emission scanning electron microscopy (FESEM) showed that microsized powder is obtained. X-ray powder diffraction (XRD) pattern is used for both phase identification and crystal structure Rietveld refinement. The structure is refined in the orthorhombic Pbnm space group. Mössbauer spectroscopy revealed traces of Fe3+ impurity. The bond valence mapping method is applied for the first time on Fe2SiO4 framework. It shows isolated, non-connected isosurfaces of constant E(Li), which further supports the assumptions of the conversion reactions. Electrochemical performances are investigated through galvanostatic cycling, cyclic voltammetry, and electrochemical impedance spectroscopy (EIS). Ex-situ XRD and Fourier transform infrared spectroscopy (FTIR) analyses are combined to monitor phase change after galvanostatic cycling and to reveal the working mechanism during electrochemical lithiation. This is the peer-reviewed version of the article: Jugović, Dragana, Milović, Miloš, Ivanovski, Valentin N., Škapin, Srečo, Barudžija, Tanja, Mitrić, Miodrag, "Microsized fayalite Fe2SiO4 as anode material: the structure, electrochemical properties and working mechanism" in Journal of Electroceramics (2021), [https://doi.org/10.1007/s10832-021-00260-9]

Thermal stability and the crystallization kinetics of a phase-separated Zr–Cu–Fe–Al bulk metallic glass were investigated using in situ high-energy synchrotron X-ray and neutron diffraction, as well as small-angle synchrotron X-ray scattering. It was revealed that this glass with excellent glass-forming ability possesses a two-step crystallization behavior. The crystalline products and their evolution sequence are more complicated than a homogeneous Zr–Cu–Al glass with average glass-forming ability. The experimental results indicate that a finely distributed nanometer-sized cubic Zr2Cu phase forms first and then transforms to a tetragonal Zr2Cu phase, while the matrix transforms to an orthorhombic Zr3Fe phase. The strength of the Zr–Cu–Fe–Al composite containing cubic Zr2Cu phase and glass matrix increases, and the plasticity also improves compared to the as-cast Zr–Cu–Fe–Al bulk metallic glass. Our results suggest that the formation of multiple and complex crystalline products would be the characteristics of the Zr–Cu–Fe–Al glass with better glass-forming ability. Our study may shed light on the synthesis of bulk-sized glass–nanocrystals composites of high strength and good plasticity.

Pure V2O5 and MnO2/V2O5 hybrid nanocomposites were synthesized by microwave-assisted method for electrochemical supercapacitor application. X-ray diffraction analysis showed the orthorhombic structure for pure V2O5 and MnO2/V2O5 nanocomposites that showed the mixed state of the orthorhombic and orthogonal phase structure of V2O5 and MnO2. The average crystalline sizes were calculated as 14 nm and 17 nm for pure V2O5 and MnO2/V2O5 nanocomposites. Scanning electron microscopy and Field emission scanning electron microscopy image analysis demonstrated the mixed state of nanoplate and small rod-like shape for V2O5 and it was transformed to nanobeads shape by the addition of MnO2. The Energy Dispersive X-Ray Analysis confirmed the presence of V and Mn compounds in the as-prepared nanocomposites. The porous nature of nanostructures was studied by Brunauer–Emmett–Teller analysis. Finally, the electrochemical analysis was recorded in 3.5 M KOH and 1 M H2SO4 electrolytes to compare its performance and suitability. The pure V2O5 nanostructure showed the maximum capacitance of 150 F/g and 95 F/g in KOH and H2SO4 electrolytes. The specific capacitance of V2O5 was enhanced to 570 F/g for the addition of 6 wt% of MnO2 in 3.5 M KOH electrolyte, whereas, in 1 M H2SO4 electrolyte, the specific capacitance was 269 F/g for the addition of 6 wt% of MnO2.

With the target to fabricate more feasible catalysts for SRM to produce hydrogen, the interaction between Ni and LaBO3 (B = Al, Cr and Fe) perovskite supports with different B-sites has been explored. To avoid the formation of big Ni grains, the Ni loading is intentionally set as low as 2 wt%. XRD and Raman results revealed that the three LaBO3 supports are composed of pure perovskite phase, but have differed fine crystal structures. While LaFeO3 and LaCrO3 can be indexed to the orthorhombic perovskite phase, LaAlO3 can be indexed to the hexagonal phase. H2-TPR and XPS results have validated that NiO has varied interfacial interactions with the LaBO3 supports through partial electron transfer from the supports to Ni. As a consequence, the active metallic Ni surface areas are in the order of 2%Ni/LaAlO3 > 2%Ni/LaCrO3 > 2%Ni/LaFeO3, well consistent with the reaction performance. Furthermore, by varying the B-site element, the abundance of the active surface oxygen species (mainly O22−) is varied, obeying the sequence of 2%Ni/LaCrO3 > 2%Ni/LaAlO3 > 2%Ni/LaFeO3, well consistent with the anti-coking ability of the catalysts. It is discovered that the change of the fine crystal structure of LaBO3 supports can influence the SRM performance of the 2%Ni/LaBO3 catalysts evidently. The reaction performance of the catalysts is mainly determined by the active Ni surface area, but the anti-coking ability is majorly decided by the amount of active oxygen species.

High transparent lead-free (1−x)K0.5Na0.5NbO3-xSr(Yb0.5Ta0.5)O3 (KNN-xSYbT, x = 0.005, 0.01, 0.02, 0.03, 0.04, 0.05) ferroelectric ceramics were synthesized by the conventional solid-phase sintering method. The effects of Sr(Yb0.5Ta0.5)O3 doping on the microstructure, phase transition, optical and electrical properties were investigated. At x = 0.01, an excellent transmittances of 52.3% in the visible region and 68.2% in the infrared region was achieved, and the optical bandgap Eg was 3.00 eV. X-ray diffraction indicates that the crystal structure of the ceramics transformed from orthorhombic phase to pseudo-cubic phase with doping of Sr(Yb0.5Ta0.5)O3. After introduction of Sr(Yb0.5Ta0.5)O3, the grain size of the ceramics changes obviously and the grains become smaller gradually. The ceramics with x = 0.01 exhibited the optimal energy storage properties with Wrec = 0.55 J/cm3 and η = 61.1%. The maximum dielectric constant of 3300 was obtained at x = 0.005. The results illustrated that the proposed system has a broad application prospect in multi-functional integrated devices.

In this work, the very rapid one-step mechanochemical synthesis of nanocrystalline ternary chalcogenide chalcostibite CuSbS2 prepared from copper, antimony, and sulfur precursors by high-energy milling for only 30 min in a planetary mill is reported. XRD confirmed the orthorhombic crystal structure of CuSbS2. The crystallite size of CuSbS2 calculated by LeBail refinement of the X-ray powder diffraction data was 25 nm. The nanocrystalline chalcostibite CuSbS2 was also confirmed by transmission electron microscopy. The purity of CuSbS2 was verified by Raman spectroscopy. The synthesized chalcostibite exhibits the specific surface area value of 2.4 m2g−1. UV–Vis spectroscopy showed the optical bandgap of CuSbS2 as 1.54 eV with wide range of absorption in visible region. Photoresponse of CuSbS2 was confirmed by I–V measurements under dark and light illumination. The proposed mechanochemical synthesis provides an alternative approach to prepare also other ternary semiconductor nanomaterials. CuSbS2 semiconductor nanocrystals have the potential to be used as light absorbers in photovoltaics.

In this work, the RMO3 (R = Pr, Nd and M = Fe, Co) perovskites had been synthesized by hydrothermal method. The structural properties of RMO3 prepared samples were investigated by using X-ray diffraction (XRD) analysis. These prepared perovskites showed the orthorhombic structure with the Pbnm space group. The Williamson-Hall method was used for determining the size of crystallites (DW–H) and lattice strains (ε) of the samples. In addition, scanning electron microscopy (SEM) was used for investigating the morphology and for determining the sizes of RMO3 particles. For magnetic characterizations of the samples, vibrating sample magnetometer (VSM) and FC and ZFC measurements had been used. The Neel temperatures (TN) of R ions were determined at TN = 29, 8 and 9 K for PrFeO3, PrCoO3, and NdCoO3 perovskites, respectively. The spin reorientation temperature (TSR) of NdFeO3 had been displayed at T = 163 K during FC and ZFC protocols. Thereafter, the Curie–Weiss law had been used for calculating the CW temperatures (θCW) and Curie constants (C) of the all samples based on FC measurements data.

In recent days, the development of low-cost, sustainable, efficient electrode materials for energy storage applications is of great interest. Herewith, Cu-doped Ca(Ti0.9Fe0.1)O3-δ (Cu:CTF) double-perovskite electroceramic, heat-treated at diverse temperatures (800–1100 °C) were prepared using sol–gel technology. X-ray diffraction pattern confirmed the orthorhombic structure of the prepared Cu:CTF perovskites. Significant traces of TiO2, CuO vanishes at elevated temperatures, which is evident from the XRD pattern. Further, the secondary phase traces were also observed in XRD, but without changing its crystal structure of Cu:CTF nanotitanate. The crystalline nature of the Cu:CTF ceramic was identified around 750 °C employing TG/DTA. UV–visible spectroscopy demonstrates the poor visible absorbance region towards the red shift with the bandgap variation of 5.28–5.42 eV. The nature of the Cu:CTF particles were analyzed using electron microscopes with the estimated particle size between 52 and 190 nm. Considering the action of temperature and frequency, complex impedance spectroscopy was utilized to analyse the inter- and intra-grain inclusions. Complex impedance spectroscopy study confirms the existence of dipole–dipole relaxation and Maxwell–Wagner (MW) polarisation for the samples heated above 900 °C. However, the a.c. test reveals the presence of conduction due to the addition of Cu2+ ions to CaTi1-xFexO3-δ perovskite, which enhances oxygen vacancies and is strongly dependent on the inhibition of the hopping conduction mechanism.

4-dimethylaminopyridine lithium nitrate crystal (4-DMAPLN) was synthesized by the slow evaporation solution growth technique. The titular crystal was subjected to various studies to recognize its physicochemical properties. The crystalline nature and orthorhombic crystal system were revealed by single crystal and powder XRD. FTIR spectroscopy study confirms the various modes of vibrations available in the titular crystal. Linear optical studies show the lower cut-off wavelength of 280 nm with an optical bandgap value (Eg) of 4.3 eV. The electrical behavior of the 4-DMAPLN crystal was studied using dielectric studies. The mechanical behavior of the grown crystal was analyzed using the Vicker’s microhardness study, revealing that the grown crystal belongs to the hard category. The second-order nonlinear optical (NLO) behavior of 4-DMAPLN crystal was measured using Kurtz–Perry powder techniques and it was found to be 1.17 times higher than reference KDP. Z-scan analysis reveals 4-DMAPLN is a suitable candidate for optical limiting applications.

This paper reports the effect of chromium’s substitution in magnetic oxides with perovskite structure La0.5Sm0.2Sr0.3Mn1-xCrxO3 (x = 0, 0.1, 0.15 and 0.2) compounds which have been produced with the glycine-nitrate process (GNP). The four compounds have an orthorhombic crystal structure with ‘Pnma’ space group. We note that they undergo a second-order paramagnetic-ferromagnetic (PM-FM) phase transition. Substitution manganese by chromium leads to a drop of the Curie temperature TC from 278 K (x = 0) to 205 K (x = 0.2). Their magnetocaloric effect has been evaluated by their magnetic entropy change $$\left(-\Delta {S}_{M}^{max}\right)$$ under a magnetic field change up to 5 T. All relative cooling power (RCP) suggests that these compounds are suitable candidates for magnetic refrigeration.

We propose a unified thermodynamic model of flow-induced crystallization of polymer (uFIC), which incorporates not only the conformational entropy reduction but also the contributions of flow-induced chain orientation, the interaction of ordered segments, and the free energy of crystal nucleus and crystal morphology. Specifically, it clarifies the determining parameters of the critical crystal nucleus size, and is able to account for the acceleration of nucleation, the emergence of precursor, different crystal morphologies and structures induced by flow. Based on the nucleation barrier under flow, we analyze at which condition precursor may occur and how flow affects the competition among different crystal forms such as orthorhombic and hexagonal phases of polyethylene. According to the uFIC model, the different crystal morphologies and structures in the flow-temperature space have been clarified, which give a good agreement with experiments of FIC.

A novel and good optical quality NLO single crystal of copper zinc hydrogen phosphate (CuZnHPO4) is grown by gel technique in silica hydrogel media. Both single crystal and powder X-ray diffraction analysis found that the orthorhombic crystal arrangement with space group Pnma and the predictable lattice parameters are a = 10.51 A, b = 18.9 A, c = 5.05 A, and α = β = γ = 905. Thermogravimetric analysis is used to perform this thermal stability of the crystals that have been produced. SEM and TEM images reveal that plate-like morphology and further plate-like growth were observed on some plates. UV spectra results reveal that the absorption of the grown crystal was found in the visible region and suggest that it can be useful for NLO applications. With increasing frequency, both the dielectric constant and the dielectric loss reduced. Moreover, the grown crystal had high conductivity and the activation energy of 0.426 eV. Photoconductivity studies of CuZnHPO4 revealed the positive photoconduction nature of the crystal. Kurtz–Perry powder SHG test was employed to determine the SHG efficiency. The estimated SHG efficiencies are 19.2 mJ and 52.6 mJ for KDP and CuZnHPO4 crystals, respectively. The results suggest that the SHG efficiency of CuZnHPO4 crystal is 2.73 times better than KDP single crystal.

The most generally used slow evaporation technique at ambient temperature is used to develop L-glutamine barium acetate (LGBA) materials for a variety of applications. The crystallinity, cell parameters (a = 16.22, b = 7.8 and c = 5.13), and space group (P212121) of the grown material are confirmed through X-Ray diffraction test and shows the grown material belongs to orthorhombic structure. The optical analysis clearly shows that LGBA crystals have higher transparency window from 233 to 800 nm, and Eg = 5.80 eV demonstrates the prepared crystals are suitable for optical applications. In addition, the important optical constants such as extinction coefficient, refractive indices, skin depth and optical conductivity are strongly depend on photon energy of the LGBA material indicating the phototunable nature of the material. The mechanical properties are validated with the aid of Vickers' microhardness measurement and it shows the work hardening coefficient of LGBA material and its value 3.7 which suggests the grown LGBA belongs to the class of soft material. Morphology of the grown material such as crystalline size, shape and purity is analyzed via SEM and HRTEM measurement. The SHG efficiency of the LGBA crystal grown is 1.33 times greater than that of the KDP crystal, because Ba+ ions strengthen the SHG efficiency of LGBA, as estimated by Kurtz and Perry's technique. Electrical results have documented the good conducting properties of LGBA crystal. The electrical study clearly identifies the grown crystal is less defective, good quality material because AC conductivity is high at high-frequency region. An antimicrobial assay validates that the LGBA substance is used to treat fungal and bacterial infections.

The new non-centrosymmetric hybrid crystal (C4H12N2)[ZnBr4] was synthesized under slow evaporation method at ambient temperature. The obtained compound is crystalized in the orthorhombic system, space group P212121, a = 8.473 (16) A, b = 11.469 (18) A, c = 12.256(2) A, V = 1191.1 (4) A3 and Z = 4. The isolated [ZnBr4]2− tetrahedra and (C4H12N2)2+cations associated together by N–H⋯Br hydrogen bonds to form layers parallel to (a, b) plane characterize the crystal structure of the Zn(II) complex. The presence of the functional groups in the crystal was proven by the real-time infrared (RTIR) spectroscopic results. The first-principles density functional theory was conducted to explore the band structure and total and partial densities of state. The hybrid compound shows a direct band gap of 4.04 eV. The evaluation of the biological activity of the synthesized compound was carried out by agar well diffusion method, indicating strong antibacterial and moderate antifungal inhibitory activities. The tested compound’s MIC was 500 µg/mL against Bacillus subtilis. As for the Kurtz–Perry powder method, it demonstrated that the second-harmonic generation measurements showed a nonlinear optical activity for the title compound (C4H12N2)[ZnBr4] with a maximum intensity of ca. 19% and 60% compared with the reference samples of urea and KDP, respectively.

Lanthanum- and zirconium-doped perovskite Ba0.5Sr0.5Fe0.9Cu0.1O3-δ ceramics, i.e., LaBa0.5Sr0.5Fe1.8Cu0.2O6-δ (LBSFC) and Ba0.5Sr0.5Fe0.85Cu0.1Zr0.05O3-δ (BSFCZ), were synthesized and characterized. The characterizations include x-ray diffraction, scanning electron microscopy, x-ray near-edge absorption spectroscopy of the Fe K-edge and Cu K-edge, iodometric titration, and electrical conductivity measurements. The structure of BSFCZ was pseudo-cubic single perovskite, whereas LBSFC was orthorhombic double perovskite. It was also discovered that the iron and copper in the octahedron-site has a mixed oxidation state with iron having 3+/4+ and copper 2+/3+. The ratio of Fe3+/Fe4+ was found to be 59/41 for LBSFC and 75/25 for BSFCZ. Similarly, copper has a mixed Cu2+/Cu3+ = 24/76 for BSFCZ and 44/56 for LBSFC. The unit cell symmetry, the presence of La3+, and the formation of Fe4+/Cu3+ are thought to be responsible for the improvement in the electrical conductivity and performance of the LBSFC. In contrast, the Zr4- stabilized perovskite structure was unfavorable for electrical conductivity. The electrical performance of the LBSFC achieved a maximum conductivity σ = 150 S/cm-1 at 500°C.

In this report, Yb0.8Ca0.2MnO3, Dy0.8Ca0.2MnO3, and Nd0.8Ca0.2MnO3 perovskite compounds have been felicitously elaborated based on a fertile cost-effective solid-state reaction strategy. Dy0.8Ca0.2MnO3 and Nd0.8Ca0.2MnO3 powders were found to manifest orthorhombic structure, whereas the Yb0.8Ca0.2MnO3 sample was found to demonstrate hexagonal structure. However, the YbO2 secondary impurity phase was evinced with the perovskite Yb0.8Ca0.2MnO3 phase. The samples’ SEM images emerged with the uniform pseudo-cubic-like structure, and the grain sizes of the perovskite materials were in the range between 250 and 600 nm. FT-IR spectrums emphasized the band peaks linked with the functional group of the perovskite manganite compounds. Magnetic moment–magnetic field dependence features asserted antiferromagnetic characteristics for Yb0.8Ca0.2MnO3 and Dy0.8Ca0.2MnO3 samples, while the Nd0.8Ca0.2MnO3 sample disclosed paramagnetic phase at room temperature. Dielectric properties elucidated the normal behavior of perovskite at room temperature. This study explores the rule of the rear earth elements on tune the properties of perovskite compounds.

Double perovskite La2−xSrxMnRuO6 (x = 0, 0.3, 0.5, 0.8, 1.0) samples were synthesized by the standard solid-state reaction method. The compounds can be well indexed as an orthorhombic structure with the space group of Pnma at room temperature. The Sr-doped samples exhibit a stronger ferromagnetic behavior than the undoped sample, which is responsible for the ferromagnetic super-exchange interaction of Mn3+-O2−-Ru4+. The Curie temperature of all samples increases with the increasing Sr2+ concentration. All the samples show a semiconducting-like behavior, and the nature of electrical conduction can be well described by Mott’s three-dimensional variable range hopping model. The appropriate Sr2+ substitution can effectively enhance the magnetoresistance effect. An enhanced negative magnetoresistance effect (~ 49%) in the La1.5Sr0.5MnRuO6 sample was observed at 25 K and 7 T.

L-Alanine (LA) is a promising nonlinear optical material from the amino acid category. The results of thorough deliberations on physiochemical and optical properties of pure and mixed forms of LA attracted many researchers. In this context, ammonium bromide added LA crystals were grown by solvent evaporation process and they were analyzed through various characterization tools. The orthorhombic crystal system and the slight intensity variation were noticed by diffraction studies. The vibrational lines of diverse functional groups and element identification were made by FT-IR and EDAX analysis, respectively. The optical properties were evaluated to witness the transparency to the visible light along with UV lower limiting wavelength of 245 nm. The surface topography and melting point were analyzed through SEM and thermal studies, respectively. Mechanical behavior was examined through hardness test. The crystal under study has shown improved second harmonic generation efficiency compared to pure LA as revealed by Kurtz powder method.

Copper(I) selenide-nanocrystalline semiconductor was synthesized via one-step mechanochemical synthesis after 5 min milling in a planetary ball mill. The kinetics of synthesis was followed by X-ray powder diffraction analysis and specific surface area measurements of milled 2Cu/Se mixtures. The X-ray diffraction confirmed the orthorhombic crystal structure of Cu2Se with the crystallite size ∼25 nm. The surface chemical structure was studied by X-ray photoelectron spectroscopy, whereby the binding energy of the Cu 2p and Se 3d signals corresponded to Cu+ and Se2− oxidation states. Transmission electron microscopy revealed agglomerated nanocrystals and confirmed their orthorhombic structure, as well. The optical properties were studied utilizing ultraviolet-visible spectroscopy and photoluminescence spectroscopy. The direct bandgap energy 3.7 eV indicated a blue-shift phenomenon due to the quantum size effect. This type of Cu2Se synthesis can be easily adapted to production dimensions using an industrial vibratory mill. The advantages of mechanochemical synthesis represent the potential for inexpensive, environmentally-friendly, and waste-free manufacturing of Cu2Se.

Lead-Free composites of (1-x)BaZr0.2Ti0.8O3-(x)Ba0.7Ca0.3TiO3 (BZT-BCT) were prepared using ferroelectric BaZr0.2Ti0.8O3 and Ba0.7Ca0.3TiO3 by solid-state reaction method with different mole fractions of x (x = 0.15, 0.30 and 0.45). The preliminary structural studies were carried out by X-ray diffraction at room temperature (RT). It revealed that the samples had both tetragonal and orthorhombic structures at room temperature. Rietveld refinement analysis of diffraction data confirmed the coexistence of the tetragonal and orthorhombic phases in the sintered samples. The average crystallite size calculated from the W–H plot of all the samples varies between 0.0416 and 0.0293 $$\mu$$ m. The dielectric and impedance relaxation properties of the (1-x)BaZr0.20Ti0.80O3-(x)Ba0.70Ca0.30TiO3 ceramics were analysed from RT–600 oC in the frequency range of 100 Hz–1 MHz. The ac conductivity variation with frequency dependence was well fitted according to Jonscher's power law. While the diffusion factor increases from 1.21 to 1.30 with increase in x from 0.15 to 0.45, indicating a composition-induced diffuse transition. The presence of two semicircles in Nyquist plot were observed, which shows the grain and grain boundary contribution in all samples. The existence of a non-Debye type of relaxation behaviour of the samples was also confirmed from impedance analysis as the centre of the semicircles lies below the real axis. At various temperatures, the frequency dependence of impedance plots has been utilized to characterize the electrical conduction of the sample which demonstrated the NTCR character (Negative Temperature Coefficient of Resistance).

The wide range of optoelectronic properties found in inorganic–organic metal halide perovskites offers the potential for numerous applications. Research on these materials remains limited due to the electronic and ionic contributions to conductivity and their soft lattice structure. As a result, the existence and impact of ferroelectricity in methylammonium lead iodide (MAPbI3) are still under debate. Here, we use a Sawyer–Tower (ST) measurement circuit to examine the variations in the polarization–electric field (P–E) hysteresis of a MAPbI3 perovskite capacitor at temperatures ranging from 100 to 300 K. Ferroelectric hysteresis was not observed in the perovskite capacitor in the temperature range. A critical point of change in P–E loops was found at roughly 160 K, which is attributed to a change in the crystal structure from the tetragonal to the orthorhombic phase. These results provide insights into understanding the material and device properties of halide perovskites.

It is proved that glycine admixtured potassium hydrogen phthalate (GKHP) single crystals were effectively developed using solvent evaporation method. Structural studies were carried out using powder X-ray method, which shows that the grown crystal belongs to orthorhombic system with the space group of Pca21. The incorporation of dopant into the crystalline material of pure KHP at different concentrations was established by FTIR spectral analysis. The grown crystals were found to be transparent in the visible section and exhibit a low cutoff wavelength of 300 nm. The optical bandgap energy of the doped crystals was found to be increased from 4 to 4.12 eV. The enhanced refractive indices of the glycine doped KHP crystals from 1.49 to 1.60 could be used for suitable optical waveguide applications. The mechanical microhardness test was carried out on the (010) plane of pure and doped KHP crystals within the applied load range of 15–100 g. The work-hardening coefficient (n) of pure KHP crystal was 2.40. However, the n-value of the doped KHP crystals was estimated to be 2.02, 1.97, and 1.93, respectively. The decreased n-value suggests the moderate hardness nature of the doped KHP single crystals. The nonlinear optical property of the crystals was affirmed by second harmonic generation (SHG) test.