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Cuprous oxide (Cu2O) is an attractive material for a number of device and industrial applications. In this study, solvothermal method has been employed to synthesize Cu2−xMnxO (0 ≤ x ≤ 0.07) nanoparticles, and the effect of Mn concentration on structural, electronic, and conducting properties has been discussed. X-ray diffraction (XRD) data confirmed that all samples crystallized in cubic structure without any impurity phases. X-rays photoelectron spectroscopy (XPS) also confirmed the incorporation of Mn in Cu2O lattice as Mn+2 in doped samples. Moreover, the presence of Cu+2 in the XPS spectra suggests that CuO is present at the surface region in the form of an amorphous thin layer on the Cu2O since it was not observed in XRD spectra. Multiple electronic transitions including those related to the presence of Mn were observed in Photoluminescence (PL) data consistent with the literature. Linear trend in the I-V characteristics was observed in both pure and doped samples due to the ohmic nature of the contact with the Ag electrode. The observed increase in conductivity with Mn content may be related to electron hopping conduction and large surface area (particle sizes ~ 11–15 nm) of the doped samples. The obtained results suggest that Mn has great potential to improve the electronic and conducting properties of Cu2O making it promising material for photocatalytic, solar energy and optoelectronic applications.

The aim of the study is establishing the possibility of using Zn nanotube arrays as a basis for design compact and lightweight elements of flexible electronics, including operating under influence of ionizing irradiation.The paper presents the results of the synthesis of Zn nanotubes obtained by electrochemical deposition in the pores of polymer matrices and the study of their structural and electrophysical properties after directional modification by ionizing radiation with different doses. Using the methods of scanning electron microscopy, X-ray diffraction and energy dispersive analysis, the structure of nanotubes having a polycrystalline structure and completely consisting of zinc was studied and it was demonstrated that irradiation with Ar8+ ions with a dose from 1 × 109 to 5 × 1011 ion/cm2 and energy 1.75 MeV/nucleon has an effect on the crystal structure of nanotubes.At high doses, localized highly defect zones arise, leading to a critical change in the structure and physical properties of the nanotubes, respectively. It is shown that the consequence of the modification of the crystal structure is a change in the electrical conductivity of nanotubes: at low doses the electrical conductivity increases, but when the threshold value is reached, it sharply decreases. The change in the crystal structure and the corresponding changes in the conductive properties of Zn nanotubes due to irradiation determine the mechanism of ionizing radiation influence on nanomaterials and determine the possibility of using Zn nanotubes arrays as a basis for creating compact and lightweight elements of flexible electronics.

Metal–ligand interactions in monomeric and polymeric transition metal complexes of Schiff base ligands largely define their functional properties and perspective applications. In this study, redox behavior of a nickel(II) N4-anilinosalen complex, [NiAmben] (where H2Amben = N,N′-bis(o-aminobenzylidene)ethylenediamine) was studied by cyclic voltammetry in solvents of different Lewis basicity. A poly-[NiAmben] film electrochemically synthesized from a 1,2-dichloroethane-based electrolyte was investigated by a combination of cyclic voltammetry, electrochemical quartz crystal microbalance, in situ UV-Vis spectroelectrochemistry, and in situ conductance measurements between −0.9 and 1.3 V vs. Ag/Ag+. The polymer displayed multistep redox processes involving reversible transfer of the total of ca. 1.6 electrons per repeat unit, electrical conductivity over a wide potential range, and multiple color changes in correlation with electrochemical processes. Performance advantages of poly-[NiAmben] over its nickel(II) N2O2 Schiff base analogue were identified and related to the increased number of accessible redox states in the polymer due to the higher extent of electronic communication between metal ions and ligand segments in the nickel(II) N4-anilinosalen system. The obtained results suggest that electrosynthesized poly-[NiAmben] films may be viable candidates for energy storage and saving applications.

A new one-dimensional coordination polymer, [Cu I I(3-Py-CHO)] n (3-Py-CHO = 3-pyridinecarboxaldehyde), consisting of an infinite copper(I)-iodide ladder chain and a pendant ligand, 3-Py-CHO, was prepared and structurally characterized using X-ray diffraction analysis. This material shows semiconducting properties with a relatively small activation energy, as shown by impedance measurements. We also estimated the electrical conductivity from a current-voltage ( I-V ) curve measured from a single crystal of the coordination polymer. [ABSTRACT FROM AUTHOR]

Abstract: New mixed-valence coordination polymers {[CuI 5CuIII5L2(C2H5CN)2]·CHCl3} n (L=piperidine-dithiocarbamate and hexamethyl-dithiocarbamate) with isomorphous infinite one-dimensional (1D) structures were prepared and structurally characterized via X-ray diffraction. These complexes comprised a mononuclear Cu(II) unit, CuIIL2, and a pentanuclear Cu(I) cluster unit, CuI 5I5(C2H5CN)2. Impedance measurements demonstrated that these Cu(I)–Cu(II) mixed-valence 1D coordination polymers displayed semiconducting behavior with low conductivities. [Copyright &y& Elsevier]

This manuscript reports the synthesis of the liquid crystalline (LC) monomer cholesteryl 4-pentenoate and its sulfone and co-polysulfone with 1-hexene. The polymers were characterized by IR,1H-NMR, differential scanning calorimetry and thermogravimetric analysis techniques. The LC phases were observed under a hot stage fitted with a polarizing optical microscope. The elemental analysis for the sulfone group was done by SEM (energy dispersive X-ray analysis) analysis. The amount of elemental sulfur present in polysulfone and co-polysulfone is 4.95 weight (%) and 5.71weight (%), respectively. The molecular weights were determined by Gel Permeation Chromatography, using tetrahydrofuran as the solvent. The number average molecular weight of the polysulfone is 5950 g/mol. The molecular weights of the co-polysulfones were found to be higher than the polysulfone. FromI–Vcharacteristics, the breaking voltage for the polymers was computed to be around 5 V. The conductivity of the polysulfone and co-polysulfones increases with increasing temperature. [ABSTRACT FROM AUTHOR]

Complex bimetallic salts of the form [M(bpy)3][Co(NCX)4] [M = Fe(II), X = S (1); M = Fe(II), X = Se (2); M = Fe(II), X = S, Se (3); M = Co(II), X = Se (4); M = Co(II), X = S, Se (5); M = Ni(II), X = S (6); M = Ni(II), X = Se (7); M = Ni(II), X = S, Se (8)] have been prepared and fully characterized various physicochemical techniques. Room temperature magnetic moments show significant antiferromagnetic coupling in the majority of complexes. Complexes 5-8 with σrt ≈ 10−8 Scm−1 are consistent with their behavior of semiconductor. [ABSTRACT FROM AUTHOR]

The use of [MIII(ox)3]3− (MIII=Ru, Rh) complexes as building blocks for hybrid molecular materials is highlighted with two different synthetic approaches. The first strategy is the combination of organic donors and [RuIII(ox)3]3− units, resulting in the radical salt of formula TTF3[Ru(ox)3]·0.5EtOH·4H2O (1) which shows coexistence of paramagnetism and semiconducting properties. The second approach is the synthesis of extended 2D bimetallic oxalato-bridged networks of general formula [FeCp2 *][MIIRh(ox)3] in which paramagnetic layers of decamethylferricinium cations are alternated with paramagnetic bimetallic layers. [Copyright &y& Elsevier]

• Cu 2− x Mn x O (0 ≤ x ≤ 0.07) nanoparticles eere synthesized by solvothermal method. • Structural, electronic, and conducting properties have been studied. • X-ray diffraction studies showed that all samples crystallized in cubic structure with no impurity phases. • Analysis of the Mn-2 p region confirmed that Mn was doped in Cu 2 O in the form of Mn+2. • Violet, blue and green emission was observed in PL data. • Linear behavior in I-V characteristics is due to the ohmic nature of the contact with the Ag electrode. Cuprous oxide (Cu 2 O) is an attractive material for a number of device and industrial applications. In this study, solvothermal method has been employed to synthesize Cu 2− x Mn x O (0 ≤ x ≤ 0.07) nanoparticles, and the effect of Mn concentration on structural, electronic, and conducting properties has been discussed. X-ray diffraction (XRD) data confirmed that all samples crystallized in cubic structure without any impurity phases. X-rays photoelectron spectroscopy (XPS) also confirmed the incorporation of Mn in Cu 2 O lattice as Mn+2 in doped samples. Moreover, the presence of Cu+2 in the XPS spectra suggests that CuO is present at the surface region in the form of an amorphous thin layer on the Cu 2 O since it was not observed in XRD spectra. Multiple electronic transitions including those related to the presence of Mn were observed in Photoluminescence (PL) data consistent with the literature. Linear trend in the I-V characteristics was observed in both pure and doped samples due to the ohmic nature of the contact with the Ag electrode. The observed increase in conductivity with Mn content may be related to electron hopping conduction and large surface area (particle sizes ~ 11–15 nm) of the doped samples. The obtained results suggest that Mn has great potential to improve the electronic and conducting properties of Cu 2 O making it promising material for photocatalytic, solar energy and optoelectronic applications. [ABSTRACT FROM AUTHOR]

Metal–ligand interactions in monomeric and polymeric transition metal complexes of Schiff base ligands largely define their functional properties and perspective applications. In this study, redox behavior of a nickel(II) N4-anilinosalen complex, [NiAmben] (where H2Amben = N,N′-bis(o-aminobenzylidene)ethylenediamine) was studied by cyclic voltammetry in solvents of different Lewis basicity. A poly-[NiAmben] film electrochemically synthesized from a 1,2-dichloroethane-based electrolyte was investigated by a combination of cyclic voltammetry, electrochemical quartz crystal microbalance, in situ UV-Vis spectroelectrochemistry, and in situ conductance measurements between −0.9 and 1.3 V vs. Ag/Ag+. The polymer displayed multistep redox processes involving reversible transfer of the total of ca. 1.6 electrons per repeat unit, electrical conductivity over a wide potential range, and multiple color changes in correlation with electrochemical processes. Performance advantages of poly-[NiAmben] over its nickel(II) N2O2 Schiff base analogue were identified and related to the increased number of accessible redox states in the polymer due to the higher extent of electronic communication between metal ions and ligand segments in the nickel(II) N4-anilinosalen system. The obtained results suggest that electrosynthesized poly-[NiAmben] films may be viable candidates for energy storage and saving applications. [ABSTRACT FROM AUTHOR]

The effect of pressing on temperature dependences of electrical conductivity σ(T) and thermoelectric power (Seebeck effect) S of single‐walled carbon nanotubes (SWCNTs) transparent films on polyester substrate has been studied. σ(T) has been described by the fluctuation‐induced tunneling model (FIT) conductance in the temperature range 20–298 K. At a temperature T < 20 K, three‐dimensional variable range hopping conductivity (VRHC) has been observed. Based on the estimation of current concentration n ≈1020 cm−3 from VRHC dependence, it has been found that metallic SWCNTs have made the main contribution to conductivity at T < 20 K. The value n obtained from S has been similar to the value obtained from VRHC estimation. The energy barrier between SWCNTs has been changed by pressing of films. Such pressing has led to increase in the electrical conductivity of the film by two orders of magnitude at room temperature. The measurement of conductivity in the process of synthesis has allowed us to control the repeatability of results and select samples with the necessary resistance values. Raman and optical spectroscopy, SEM and TEM have been used to determine the structural and geometric characteristics of the SWCNTs. The effect of pressing on the temperature dependences of electrical conductivity σ(T) and thermoelectric power of single‐walled carbon nanotubes (SWCNTs) films is studied. σ(T) is described by the fluctuation‐induced tunneling model in the temperature range 20–298 K. At T < 20 K, three‐dimensional variable range hopping conductivity is observed. The energy barrier between SWCNTs is changed by pressing of the films. [ABSTRACT FROM AUTHOR]