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Polyvinyl alcohol (PVA) and Neodymium (III) oxide (Nd2O3) were combined to synthesized flexible innovative PVA/Nd2O3 polymer composite samples utilizing a solution casting approach for use in dielectric devices. The XRD, FTIR, and SEM methods are all investigated to characterize the composite films. In a frequency of 50 Hz to 5 MHz, the effects of additive Nd2O3 on the dielectric behavior of PVA were recorded. The PVA/Nd2O3 composite films were successfully fabricated, as shown by XRD and infrared spectroscopy. The scanning microscopy pictures showed that the Nd2O3 was loaded and distributed uniformly throughout the PVA. After the incorporation of Nd2O3, the composite PVA/Nd2O3 has a conductivity of 6.82 × 10−9 S·cm−1, while the PVA has a conductivity of 0.82 × 10−9 S·cm−1. Another improvement is the decrease in the relaxation time from 14.2 × 10−5 s for PVA to 6.35 × 10−5 s for PVA/Nd2O3, and an increase in the dielectric constant of 0.237 for PVA to 0.484 at a frequency of 100 Hz. The results showed that the composite samples have considerable changes as flexible films in different applications, including batteries and electronic circuits. [ABSTRACT FROM AUTHOR]

[Display omitted] • Effect of Er3+ ion doped Mg-Zn nanoparticles were synthesized. • XRD, DAX, FE-SEM, Uv-Drs, TGA-DTA, and FT-IR to confirm the nano-range particles with spinel ferrites. • The nanoferrites demonstrated ferromagnetic behaviour at 300 K and 5 K in VSM properties. • Advantageous for in industries like nanoelectronics devices, detectors, imaging devices, super-paramagnetic coils, and magnets. A series of Mg-Zn ferrites with Er3+ ion doping in the shape of cubic spinel were produced using the citrate sol–gel auto-combustion process known as Mg 0.5 Zn 0.5 Er 0.1 Fe 1.9 O 4 (MZE) (calculated at 400, 550, 700, 850, and 1000 °C), and the same was confirmed with the XRD diffractograms. It was possible to understand the presence of hydrated water, which degrades behavior. Hence, the powders created were sintered at various temperatures for four hours. After that, it was observed that the cubic spinel phase was free of impurities. The as-prepared spinel Mg-Zn ferrite nanoparticles also showed a specified behaviour, according to the results. The SEM, UV–Vis spectroscopy, FT-IR (Fourier transform infrared) spectroscopy, TG-DTA (thermogravimetric and differential thermal analysis), XRD (X-ray diffractometer), LCR metre, and VSM (vibrating sample magnetometer) were the characterization techniques used to examine the samples' structural, optical, dielectric, and magnetic properties. A microstructure investigation was done using FESEM analysis. Based on these FESEM measurements, the nanoparticles' sphere-shaped structure was confirmed. FT-IR spectroscopy has been employed to examine the chemical bonds in the spinel ferrite. There is evidence of a shift in bands ν 1 and ν 2. The produced materials' semiconducting qualities are demonstrated by the optical band gap energy, which is in the range of 1.648–1.798 eV. Variation of dielectric parameters with Er doping was measured in the frequency range from 100 Hz to 1 MHz at room temperature (RT) and at temperatures of 100–400 °C. These results were very well supported by Maxwell-Wagner interfacial polarization. The dielectric properties were observed to decrease with an increase in frequency due to calcinated MZE samples. The magnetic properties of ferrite nanoparticles were investigated in detail at 300 K and 5 K. Early signs of superparamagnetic behaviour have been observed in the prepared sample. It is used in industries like nanoelectronic devices, detectors, imaging devices, super-paramagnetic coils, and magnets. [ABSTRACT FROM AUTHOR]

The compounds [2‐(Me2NCH2)C6H4]2SbL (L = ONO2 (2), OSO2CF3 (3)) and [PhCH2N(CH2C6H4)2]SbL (L = ONO2 (5), OSO2CF3 (6)) were prepared by reacting [2‐(Me2NCH2)C6H4]2SbCl (1) and [PhCH2N(CH2C6H4)2]SbCl (4), respectively, with the appropriate silver(I) salt in a 1:1 molar ratio. The new species 2–6 were structurally characterized in solution using multinuclear NMR and in the solid state using infrared spectroscopy. The solid‐state structures for compounds 2, 4 and 6, as well as for the hydrolysis ionic product [{2‐(Me2N+HCH2)C6H4}{2‐(Me2NCH2)C6H4}SbOH][CF3SO3]− (3h) were determined using single‐crystal X‐ray diffraction. Medium to strong intramolecular N→ Sb interactions were observed in all these four compounds, thus resulting in hypercoordinated organoantimony(III) species 14‐Sb‐6 in 2 and 10‐Sb‐4 in the cation of 3h and in 4 and 6. Compounds 1–6 and the starting amines PhCH2NMe2 and PhCH2N(CH2C6H4Br‐2)2 were investigated as catalysts in the Henry (nitroaldol) addition of nitromethane to benzaldehyde. The activity of compounds 1–6 resulted as an effect of the cooperation of the positively charged antimony with the negatively charged nitrogen. [ABSTRACT FROM AUTHOR]

• FT-IR analysis of PVA/PEG blend shows amendments in the intensity upon gamma-irradiation. • XRD pattern of PVA/PEG blend shows that the intensity of peak is influenced according to the values of gamma doses. • The gamma irradiation is a good technique for enhancing surface roughness. • An enhancement was observed in the optical and fluorescence properties of irradiated PVA/PEG blend films. This study looked at the resultant influence by γ-radiation upon the structural changes, optical and photoemission characteristics in blends of poly-vinyl-alcohol/poly-ethylene–glycol. The PVA/PEG blend films are fabricated using a blending and casting method with a 50/50 ratio. The dried films were exposed to various γ doses 30, 60, 90, and 120 kGy. The effects of γ-rays upon the properties of the dried films were examined by FTIR, XRD, surface roughness, optical microscope, UV/Vis, and photoemission techniques. FTIR spectrum shows that the band intensities of irradiated PVA/PEG are considerably lower at 30 kGy compared to PVA and PVA/PEG blend, which is attributable to the scissioning process. Also, by increasing γ-exposure dose crosslinking process takes place. The films are shown to be semi-crystalline by the XRD pattern, which also shows that they contain both crystalline and amorphous phases and are affected by the value of the -dose. An increase in surface roughness is monitored as the γ dose increases. The UV–Vis data demonstrated that the edge of absorbance changed considerably by increasing γ-doses. One can noticed that the investigated optical parameters are altered by γ-radiation. As γ-dose rises, an increase in the index of refraction is noticed. The photoemission spectra show that the PVA/PEG blend films are γ-ray sensitive, especially with higher doses of irradiation due to the growing defects in the irradiated films. [ABSTRACT FROM AUTHOR]

Layered Ni-rich Li[Ni 0.6 Mn 0.2 Co 0.2- x M x ]O 2 cathode materials ( x  = 0, 0.05; M  = Al, Fe, Sn) are synthesized via a co-precipitation synthesis route and the effect of dopants on the structure and electrochemical performance is investigated. All synthesized materials show a well-defined layered structure of the hexagonal α -NaFeO 2 phase investigated by X-ray diffraction (XRD). Undoped LiNi 0.6 Mn 0.2 Co 0.2 O 2 exhibits a discharge capacity of 170 mAh g −1 in Li-metal 2032 coin-type cells. Doped materials reach lower capacities between 145 mAh g −1 for Al and 160 mAh g −1 for Sn. However, all doped materials prolong the cycle life by up to 20%. Changes of the lattice parameter before and after delithiation yield information about structural stability. A smaller repulsion of the transition metal layer during delithiation in the Sn-doped material leads to a smaller expansion of the unit cell, which results in enhanced structural stability of the material. The improved structural stability of Sn-doped NMC cathode active material is proven by thermal investigations with the help of Differential Scanning Calorimetry (DSC) and Thermogravimetric Analysis (TGA). [ABSTRACT FROM AUTHOR]

A new organic proton transfer complex of creatininium 4-nitrobenzoate (C4NB) has been synthesized and its single crystals were grown successfully by slow evaporation technique. The grown single crystal was subjected to various characterization techniques like single crystal X-ray diffraction (SCXRD), FTIR, FT-Raman and Kurtz-Perry powder second harmonic generation (SHG). The SCXRD analysis revealed that C4NB was crystallized into orthorhombic crystal system, with noncentrosymmetric (NCS), P 2 1 2 1 2 1 space group. The creatininium cation and 4-nitrobenzoate anion were connected through a pair of N __ H⋯O hydrogen bonds (N(3) __ H(6) ⋯ O(3) (x+1, y, z) and N(2) __ H(5) &ctdot O(2) (x-1/2, -y-1/2, -z+2)) and fashioned a R 2 2 ( 8 ) ring motif. The crystal structure was stabilized by strong N __ H⋯O and weak C __ H⋯O intermolecular interactions and it was quantitatively analysed by Hirshfeld surface and fingerprint (FP) analysis. FTIR and FT-Raman studies confirmed the vibrational modes of functional groups present in C4NB compound indubitably. SHG efficiency of grown crystal was 4.6 times greater than that of standard potassium dihydrogen phosphate (KDP) material. Moreover, density functional theory (DFT) studies such as Mulliken charge distribution, frontier molecular orbitals (FMOs), molecular electrostatic potential (MEP) map, natural bond orbital analysis (NBO) and first order hyperpolarizability (β 0 ) were calculated to explore the structure-property relationship. [ABSTRACT FROM AUTHOR]

The crystallographic structure of (11 wt.%)CuO-(6 wt.%)CeO/γ-AlO has been studied and compared with (11 wt.%)CuO/γ-AlO under reducing conditions, using time-resolved in situ X-ray diffraction in the temperature range 25-800 °C. In CuO-CeO/AlO, H-TPR reduces the CuO phase to Cu, while in CH-TPR reduction follows a two-step pathway via CuO. A thermal treatment in He also induces reduction for CuO, albeit at higher temperature. In addition to CuO reduction, the CeO promoter in CuO-CeO/AlO is also partially reduced, without crystallographic transition, regardless of the atmosphere and at similar temperature where reduction of CuO occurs. Supported CuO as in CuO-CeO/AlO or CuO/AlO, is more readily reduced by thermal treatment in He than unsupported CuO and CuO. Moreover, the addition of CeO to the CuO-CeO/AlO catalyst allows for enhanced reducibility of CuO, compared to CuO/AlO. The CuO phase in CuO-CeO/AlO is reduced to CuO and partly to Cu at 700 °C and mainly to Cu at 800 °C in He flow. The thermal reduction of CuO-CeO/AlO requires an apparent activation energy of 216 kJ/mol. Graphical Abstract: An isothermal reduction treatment at 800 C in He reduces CuO-CeO/AlO, as demonstrated by time-resolved in situ X-ray diffraction. Supported CuO are more easily reduced by thermal treatment compared to unsupported CuO and CuO. The CuO phase in CuO-CeO/AlO is reduced to CuO and partly to Cu at 700 °C and mainly to Cu at 800 °C in He flow (see figure) [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Abstract: Nanosized multiferroic La1−x Al x FeO3 (0.00≤x≤0.20) samples were successfully synthesized by the citrate technique without subsequent heat treatment. All the prepared samples revealed single phase orthorhombic structure of space group Pbnm. XRD data revealed that the lattice parameters (a) decrease with increasing Al content. The magnetic susceptibility (χ M) was enhanced significantly from 0.36 to 0.68emu/gmole from LaFeO3 to La0.8Al0.2FeO3 respectively. The values of magnetization (M) and effective magnetic moment (μ eff) were found to increase with increasing Al content. The enhancement of the physical and structural properties of the investigated multiferroic is possibly due to the changes in the lattice parameters, tolerance factor as well as crystallite size caused by aluminum substitution. [Copyright &y& Elsevier]

Abstract: Structural and optical properties of Ge35Co x Te65 alloys where x=10, 15 and 25at% in the bulk state were investigated using X-ray diffraction (XRD), scanning electron microscope (SEM) and Fourier transformation infrared spectroscopy. Replacement of Te by Co leads to appearance of cubic Co2Ge3Te3 phase at higher Co values. All of obtained samples have multiphase structure. The final composition of the prepared material significantly depended on the preparation method. SEM shows that all samples have different types of grains corresponding to the multiphase structure; their size was in the range 5–10μm. IR spectra of the Ge–Co–Te alloy show a phonon absorption in the spectral range 1000–800cm−1. [Copyright &y& Elsevier]

Chalcogen-centred organophosphorus ligands (L) with different degrees of flexibility were used in hypercoordinated triorganotelluronium complexes of type [{2-(Me 2 NCH 2)C 6 H 4 } n Ph 3-n Te]L (n = 1–3). S⋅⋅⋅Te and Se⋅⋅⋅Te secondary interactions resulted in dimeric associations in 2 and cation–anion assemblies in 6 , respectively. • Compounds of type [{2-(Me 2 NCH 2)C 6 H 4 } n Ph 3-n Te]L (L = organophosphorus ligand). • C,N -chelating behaviour of the 2-(Me 2 NCH 2)C 6 H 4 groups. • [{2-(Me 2 NCH 2)C 6 H 4 }Ph 2 Te][(SePPh 2) 2 N] show Se⋅⋅⋅Te secondary interactions. • Dimeric associations in [{2-(Me 2 NCH 2)C 6 H 4 }Ph 2 Te][S 2 PMe 2 by bridging Me 2 PS 2 ligands. • Supramolecular networks by H⋅⋅⋅E (E = S, Se) secondary bonding. Triorganotelluronium complexes of type [{2-(Me 2 NCH 2)C 6 H 4 } n Ph 3-n Te]L [(L = S 2 PMe 2 , n = 3 (1), 1 (2); L = (EPPh 2) 2 N, E = S, n = 3 (3); E = Se, n = 3 (4), 2 (5), 1 (6) and L = (SPPh 2)(O 2 SC 6 H 4 CH 3 -4)N, n = 3 (7), 2 (8), 1 (9)] were obtained by salt metathesis reactions between triaryltelluronium halides of type [{2-(Me 2 NCH 2)C 6 H 4 } n Ph 3-n Te]X (X = Cl, Br) and the alkali metal salt of the corresponding organophosphorus acid in a 1:1 molar ratio. The new ionic species were characterized by multinuclear NMR spectroscopy and mass spectrometry. The NMR spectra show similar resonances for each series of triorganotelluronium complexes (1 and 2 , 3 – 6 and 7 – 9). The 1H NMR spectra suggest intramolecularly coordinated pendant arms in solution for compounds bearing two or three 2-(Me 2 NCH 2)C 6 H 4 groups. Single-crystal X-ray diffraction studies revealed strong N→Te intramolecular interactions in compounds 2 , 4 , 6 and 7 , which result in hypercoordinated triorganotelluronium(IV) cations with different distorted coordination geometries. Further secondary bonding interactions (S⋅⋅⋅Te in 2 and Se⋅⋅⋅Te in 6) lead to cation–anion associations, while H⋅⋅⋅E (E = S, Se) contacts between cations and anions resulted in different supramolecular networks in 2 , 4 and 6 and in discrete cation–anion pairs in 7. [ABSTRACT FROM AUTHOR]