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Mg/B co-doped ZnO nanoparticles were synthesized by using the sol–gel technique to investigate the role of the defects on the structural, biological and photocatalytic properties. Single phases with ZnO wurtzite hexagonal structures were observed in the X-ray diffraction measurements. Scanning electron microscopy and transmission electron microscopy were used to determine the surface, particle size, and shapes of the nanoparticles. Electron dispersive spectroscopy was used to determine the elemental compositions of the nanoparticles. Photoluminescence spectrophotometry and positron annihilation lifetime spectroscopy were used to study the defect type, density and crystal quality of Mg/B co-doped ZnO nanoparticles. A broad visible emission band (including violet–blue-orange and red emissions) was observed. The violet– blue-orange and red emissions could be attributed to the O vacancies (VO), interstitial Zn (Zni), Zn vacancies (VZn), and the double charged oxygen vacancy (VO (??) ), which were strongly dependent on the synthesis conditions and doping ratio. SEM images revealed that Mg/B-co-doped ZnO nanoparticle magnifications were dense, quasispherical, and agglomerating. The photocatalytic activities and blood compatibilities of Mg/B co-doped ZnO nanoparticles were studied by the photocatalytic degradation tests of crystal violet (CV) and hemolysis tests, respectively.

Polybutylene terephthalate (PBT) is a semi-crystalline engineering thermoplastic polyester. PBT offers rapid molding cycles, high heat resistant, crystallinity, fatigue resistance, strength and rigidity, excellent electrical properties, creep resistance, reproducible mold shrinkage and chemical resistance. In this study, PBT was loaded with synthetic graphite and carbon fiber at different weight fractions (10-40 wt.%). PBT-based composites were fabricated by the melt mixing process by using a co-rotating twin screw extruder then thermal, mechanical and morphological properties of filled PBT composites was investigated. Weight fraction of carbon fiber (up to 30 wt.%) increases the tensile strength and flexural strength of PBT, but synthetic graphite loading decreases the tensile strength and flexural strength of PBT. The highest in-plane and through-plane thermal conductivity values were obtained as 9.24 for 40 wt.% synthetic graphite filled composite and 3.41 W/mK for 40 wt.% carbon fiber reinforced composite, respectively. Carbon fiber was found to be more effective in increasing the through-plane thermal conductivities than synthetic graphite., Ege University Research Projects Coordination [18-MUH-027], The author(s) received funding from Ege University Research Projects Coordination (Project no: 18-MUH-027).

Enhanced sweat sensors lead to real-time, sustained,noninvasivetracking of sweat loss, ensure insight into individual health conditionsat the molecular level, and have obtained prominent interest for theirhopeful implementations in customized health tracking. Metal-oxide-basednanostructured electrochemical amperometric sensing materials arethe best selection for continuous sweat monitoring devices owing totheir high stability, high-sensing capacity, cost-effectiveness, miniaturization,and wide applicability. In this research, CuO thin films have beenfabricated by successive ionic layer adsorption and reaction technique(SILAR) with and without the addition of Lawsonia inermis L. (Henna, (LiL)) leaf extract (C10H6O3, 2-hydroxy-1,4-naphthoquinone) with a high-sensitive andrapid response for sweat solution. Despite the pristine film beingresponsive to the 65.50 mM sweat solution (S = 2.66),the response characteristic improves to 3.95 for the 1.0% LiL-implementedCuO film. Unmodified, 1.0% LiL and 3.0% LiL-substituted thin-filmmaterials assure considerable linearity with linear regression ranges, R (2), of 0.989, 0.997, and 0.998, respectively.It is noteworthy here that this research aims to determine an enhancedsystem that could potentially be implemented in real-life sweat-trackingadministrations. Real-time sweat loss tracking capabilities of CuOsamples was found to be promising. Derived from these outcomes, weconcluded that the fabricated nanostructured CuO-based sensing systemis a useful application for the continuous observation of sweat lossas a biological argument and compatibility with other microelectronictechnologies.

LuFe1-xOsxO3 (x = 0, 0.05, and 0.10) compounds were synthesized and their resistivity, real and imaginary portion of the impedance and frequency-dependent loss tangent were examined at varied temperature settings (from - 100 degrees C to 100 degrees C by 20 degrees C step). Impedance and resistivity values increased as a result of the doping procedure, whereas activation and loss tangent values decreased. According to the X-ray photoelectron spectroscopy (XPS) study, Lu possesses a 3 + oxidation state, and the oxygen 1s spectrum displayed peaks for lattice oxygen and oxygen vacancy. Particle agglomeration and void formation were visible in scanning electron microscopy (SEM) pictures. Single and double oxygen vacancies and ion hopping between Fe2+ and Fe3+ ions were responsible for the reported activation energies. The frequency-dependent loss tangent results showed that all compounds have a highly low loss factor even at 100 degrees C.

Carbon‐fiber reinforced polymer (CFRP) composites are replacing metal alloys in aerospace structures, but they can be vulnerable to lightning strike damage if not adequately protected due to the poor electrical conductivity of the polymeric matrix. In the present work, to improve the conductivity of the CFRP, two electrically conductive epoxy formulations were developed via the addition of 0.5 wt% of graphene nanoplatelets (GNPs) and a hybrid of 0.5 wt% of GNPs/carbon nanotubes (CNTs) at an 8:2 mass ratio. Unidirectional CFRP laminates were manufactured using resin‐infusion under flexible tooling (RIFT) and wet lay‐up (WL) processes, and subjected to simulated lightning strike tests. The electrical performance of the RIFT plates was far superior to that of the WL plates, independent of matrix modification, due to their greater carbon‐fiber volume fraction. The GNP‐modified panel made using RIFT demonstrated an electrical conductivity value of 8 S/cm. After the lightning strike test, the CFRP panel remains largely unaffected as no perforation occurs. Damage is limited to matrix degradation within the top ply at the point of impact and localized charring of the surface. The GNP‐modified panel showed a comparable level of resistance against lightning damage with the existing copper mesh technology, offering at the same time a 20% reduction in the structural weight. This indicates a feasible route to improve the lightning strike damage resistance of carbon‐fiber composites without the addition of extra weight, hence reducing fuel consumption but not safety.

Pressure-dependent delafossite CuCrO2 samples are synthesized by the solid-state reaction method to investigate the effect of defects formed under pressure on the structure and magnetic properties of CuCrO2. X-ray Diffractometer, Scanning Electron Microscope (SEM), Energy Dispersive Spectroscopy (EDS), Photoluminescence spectroscopy (PL), and Vibrating Sample Magnetometer (VSM) are used the characterize CuCrO2 samples. All samples give almost the same structural phase properties without any secondary peaks. All magnifications of SEM images show no melting of the sample and thus the annealing temperature of the samples is optimized. Photoluminescence measurements reveal that near band emission is caused by excitonic transitions between electrons and holes, the stronger the UV emission of the sample, the higher the crystallization quality, and fewer defects occur. Magnetic investigations depict that the spins are antiferromagnetically oriented while they have a magnetic moment component perpendicular to the plane. Therefore, each grain should be considered a weak magnet. Temperature-dependent magnetic moment measurements exhibit a slight variation in moment values. The reason behind this should be attributed to the grain size related to the formation of grains by applied pressure.

In this study, CdO films were successfully obtained by using a homemade chemical spray pyrolysis technique. The crystal structures of the CdO thin films improved due to an increase in the substrate temperature when the spray time was kept constant. Additionally, CdO film deposited at 250 degrees C exhibited amorphous crystal structure. The surface morphology of the samples was evaluated by scanning electron microscope (SEM) and it was observed that well-defined granules started to be clearly seen when the substrate temperature increased. Optical properties of CdO films were also investigated by using an ultraviolet-visible (UV-Vis) spectrophotometer, and the optical band gap of CdO varied from 2.57 eV to 2.73 eV with increasing substrate temperature. The electrical performance of the CdO films in the Au/CdO/p-Si device were determined by I-V measurements. According to the results, it was found that diode parameters depend on the changing properties of CdO in terms of the substrate temperature.

Substituted SrCoO3 perovskites have been proposed as promising mixed ionic electronic conductors for a range of applications including intermediate temperature solid oxide fuel cells (IT-SOFCs), electrolysers and thermochemical water splitting reactors for H2 production. In this work we investigate the effect of sample exposure to water in substituted SrCoO3 powders and thin films and correlate it with the degradation of oxygen mobility and kinetics. SrCo0.95Sb0.05O3−δ (SCS) thin films have been deposited on different single crystal substrates by pulsed laser deposition (PLD). After water cleaning and post annealing at 300 °C, the sample surface presented an increase of the SrO-surface species as observed by ex situ X-ray Photoemission Spectroscopy (XPS) analysis. This increase in SrO at the sample surface has also been confirmed by the Low Energy Ion Scattering (LEIS) technique on both SCS thin film and powder. Thermochemical water splitting experiments on SCS and SrCo0.95Mo0.05O3−δ (SCM) powder revealed a phase degradation under water oxidising conditions at high temperature with the formation of the trigonal phase Sr6Co5O15. Transmission Electron Microscopy (TEM) analysis of SCS powder treated with water suggests that this phase degradation could already superficially start at Room Temperature (RT). By isotope exchange depth profile experiments on SCS thin films, we were able to quantify the oxygen diffusivity in this SCS surface decomposed layer (D* = 5.1 × 10−17 cm2 s−1 at 400 °C). In the specific case of bulk powder, the effect of water superficial decomposition translates into a lower oxidation and reduction kinetics as demonstrated by comparative thermogravimetric analysis (TGA) studies.

The objective of this study is to synthesize ZnO and Mg doped ZnO (Zn1-xMgxO) nanoparticles via the sol-gel method, and characterize their structures and to investigate their biological properties such as antibacterial activity and hemolytic potential.Nanoparticles (NPs) were synthesized by the sol-gel method using zinc acetate dihydrate (Zn(CH3COO)(2) .2H(2)O) and magnesium acetate tetrahydrate (Mg(CH3COO)(2) .4H(2)O) as precursors. Methanol and monoethanolamine were used as solvent and sol stabilizer, respectively. Structural and morphological characterizations of Zn1-xMgxO nanoparticles were studied by using XRD and SEM-EDX, respectively. Photocatalytic activities of ZnO and selected Mg-doped ZnO (Zn1-xMgxO) nanoparticles were investigated by degradation of methylene blue (MeB). Results indicated that Mg doping (both 10% and 30%) to the ZnO nanoparticles enhanced the photocatalytic activity and a little amount of Zn0.90Mg0.10O photocatalyst (1.0 mg/mL) degraded MeB with 99% efficiency after 24 h of irradiation under ambient visible light. Antibacterial activity of nanoparticles versus Escherichia coli (E. coli) was determined by the standard plate count method. Hemolytic activities of the NPs were studied by hemolysis tests using human erythrocytes. XRD data proved that the average particle size of nanoparticles was around 30 nm. Moreover, the XRD results indicated that the patterns of Mg doped ZnO nanoparticles related to ZnO hexagonal wurtzite structure had no secondary phase for x

In the presented study, the performance improvement of Au/PTCDA/n-Si diodes was demonstrated with the help of pre-irradiation of PTCDA powders. The crystallographic analysis was carried out by X-ray diffraction method after the pre-irradiation of PTCDA powders. After the vacuum deposition of pre-irradiated (PI) and unirradiated (UI) PTCDA thin films, the Au/PTCDA/n-Si diodes were fabricated. The I-V, C-V, and G/omega-V characteristics were analyzed for Au/PTCDA/n-Si diodes with UI PTCDA as an interfacial layer (D1-pristine) and PI PTCDA with 30 kGy as an interfacial layer (D2). Radiation-induced effects on the produced diodes were investigated with parameters of the barrier height (phi(Bo)), series resistance (R-s), and the density of interface states (N-SS) and compared to the parameters of the pristine diode. It was observed that the electrical characteristics of Au/PTCDA/n-Si diodes, for D1 and D2, were highly influenced by the irradiation. Thus, the device performance could be improved with the pre-irradiation process. By modifying the HF-LF capacitance method to the UI-PI capacitance method, we successfully calculated the radiation-induced N-SS values without using C-V measurement at two different frequencies.

International Conference on Photovoltaic Technologies (PVCon) -- JUL 04-06, 2018 -- Middle E Tech Univ, Culture & Convent Ctr, Ankara, Turkey, WOS: 000499762300011, In the present study, using a large area roll-to-roll DC magnetron sputtering system deposition of ITO thin films on polyethylene terephthalate (PET) substrates were achieved. In order to investigate the effect of growth conditions on the film properties all through the deposition process, optical emission spectroscopy (OES) analysis have been accomplished in a governable way. The consequences of Oxygen partial pressure and film thickness on electrical, and optical properties of the films were determined. It was shown that the intensity of optical emission peaks are subjected to the discharge power and as well as the O-2/Ar flow ratio. Large area, uniform ITO films with relatively high transparency and low electrical resistivity (R(2)(

Herein, we report on synthesizing pure and aluminum (Al) doped cadmium oxide (CdO) thin films onto glass slides by successive ionic layer adsorption and reaction (SILAR) method. The optical, electrical, structural, and morphological evaluations were conducted for the produced samples after the grown thin films heat treated in a convection ashing furnace at 200 degrees C. X-ray diffraction (XRD) results disclosed that the prepared samples posses the polycrystalline cubic phase of CdO material and the (1 1 1) plane was the preferred growth orientation. Besides, the XRD analysis strongly suggested that the integration of aluminum into the CdO lattices completed as no other phases, such as Cd, Al, or related oxides, were present in the diffraction patterns. From the field emission scanning electron microscope (FE-SEM) images, it was noticed that Al doping concentration changed the surface morphologies. Energy dispersive X-ray analysis (EDAX) confidently proves the presence of Al as a result of the SILAR process. The optical properties were assessed by performing Ultraviolet-visible spectroscopy (Uv-vis), and it was observed that the optical bandgap increased from 2.5 eV to 3 eV due to the increased percentages of Al content in the Al:CdO nanostructures. The Photoluminescence (PL) spectrum evidently showed that the PL emission intensity of prepared samples was directly influenced over varying Al content in the CdO nanostructures. The electrical features of the SILAR derived CdO thin films uncovered that the resistivity of samples showed increment with the Al doping, thus the electrical conductivity of the grown samples decreased in return.

Cuprous oxide (Cu2O) nanostructures on porous silicon (PSi) were obtained by an electrochemical deposition method. The effects of current density and deposition time on structural, optical and I-V characteristics of PSi/ Cu2O nanostructures were investigated by scanning electron microscopy (SEM), X-ray diffraction (XRD) methods, diffuse reflectance spectra and current-voltage (I-V) measurements. SEM analysis revealed that the shape of Cu2O nanostructures was mostly truncated octahedral and pyramid, and their size increased with increasing deposition time and current density. From XRD analysis, it was found that Cu2O nanostructures were polycrystalline, cubic phase and their preferential orientation was along the [111] direction. In addition, it was found that with increasing current density, the average crystallite size of Cu2O nanostructures decreased, whereas FWHM, micro deformation and dislocation values increased. The diffuse reflectance spectra indicated that the average reflectivity of PSi/Cu2O samples obtained in 30 and 60 min deposition times are about 19%. The current-voltage (I-V) measurements of PSi/Cu2O samples at room temperature (300 K) and in the dark environment revealed that samples exhibited rectifier properties and behaved like a typical p-n junction diode. In addition, it was found that the I-V parameters obtained from thermionic emission and Cheung's model are found to depend on the deposition time and current density. The PSi/Cu2O sample prepared at 0.5 mA/cm2 for 60 min had the smallest ideality factor and series resistance among all samples. The values of ideality factor and barrier height were determined using the conventional thermionic emission (TE) model and Cheung's model and the obtained results have been compared with each other., Ege University Scientific Research Projects Coordination Unit [FKB-2019-20632], This study is supported by Ege University Scientific Research Projects Coordination Unit. Project Number: FKB-2019-20632.

Copper oxide (CuO) thin films were grown on glass substrates by performing ultrasonic spray pyrolysis (USP) method at different substrate temperatures (300 ?C, 400 ?C, 450 ?C, and 500 ?C). The prepared CuO thin films were characterized by using X-ray diffraction (XRD), scanning electron microscope (SEM), x-ray photoelectron spectroscopy (XPS), energy dispersive x-ray analysis (EDX), UV-visible spectroscopy, and photoluminescence (PL) spectroscopy measurements in order to assess the effects changed substrate temperature on structural, morphological, and optical properties of the grown materials. Also, the suitability of the grown films as electrodes in supercapacitor applications was investigated with respect to variable substrate temperatures. The XRD patterns revealed that the samples were polycrystalline in nature exhibiting tenorite phase of CuO structure preferential orientation along (11 1) plane and the corresponding crystallite size ranged from 28.14 nm to 67.98 nm. The SEM images displayed morphological modifications in the prepared CuO thin films as the substrate temperatures incresed. The XPS and EDX analyses confirmed the successful deposition of aimed materials on the fabricated thin films. It was also obtained that optical absorbance decreased due to the increased substrate temperatures and optical energy bandgaps changed between 1.53 eV and 1.71 eV as the substrate temperatures varied. The electrochemical supercapacitive features of the CuO nanostructures thin films were studied with the help of cyclic voltammetry (CV), galvostatic charge-discharge (GCD) and electrochemical impedance spectroscopy (EIS).

Undoped and Cr-doped zinc oxide (ZnO) thin films were deposited on the glass and p-Si substrates by the chemical spray pyrolysis technique. The films were characterized by x-ray diffractometry (XRD) and UV-visible spectrometry, and electrical characterization was achieved by using the films as an interfacial layer between the Au and p-Si. The XRD results confirmed the undoped and Cr-doped ZnO thin film crystalline structures. UV-visible spectra provided the transmittance plots and band gap energy values. I-V measurements were performed on the fabricated Au/ZnO/p-Si and Au/ZnO:Cr/p-Si devices to determine the effect of the ZnO interfacial layer on their performance. Various junction parameters, such as the ideality factor, barrier height, and series resistance, were calculated from the I-V measurements by various techniques, and have been discussed in detail. A 100-mW/cm(2) power intensity light was exposed on the Au/ZnO:Cr/p-Si device to see the photodiode behavior as well as to determine light sensitivity parameters such as photosensitivity and detectivity. The results highlight that the Au/ZnO:Cr/p-Si device can be thought of for optoelectronic applications., Sirnak University Research fund [2021], The authors would like to thanks Dr. Hatice Kacus for her technical support in this research. This study was supported by Sirnak University Research fund with Project Number 2021.FNAP.06.02.01.

We show how sintering in different atmospheres affects the structural, microstructural, and functional properties of ~30 μm thick films of K0.5Na0.5NbO3 (KNN) modified with 0.38 mol% K5.4Cu1.3Ta10O29 and 1 mol% CuO. The films were screen printed on platinized alumina substrates and sintered at 1100 °C in oxygen or in air with or without the packing powder (PP). The films have a preferential crystallographic orientation of the monoclinic perovskite phase in the [100] and [−101] directions. Sintering in the presence of PP contributes to obtaining phase-pure films, which is not the case for the films sintered without any PP notwithstanding the sintering atmosphere. The latter group is characterized by a slightly finer grain size, from 0.1 μm to ~2 μm, and lower porosity, ~6% compared with ~13%. Using piezoresponse force microscopy (PFM) and electron backscatter diffraction (EBSD) analysis of oxygen-sintered films, we found that the perovskite grains are composed of multiple domains which are preferentially oriented. Thick films sintered in oxygen exhibit a piezoelectric d33 coefficient of 64 pm/V and an effective thickness coupling coefficient kt of 43%, as well as very low mechanical losses of less than 0.5%, making them promising candidates for lead-free piezoelectric energy harvesting applications.

Significant progress on parameter-free calculations of carrier mobilities in real materials has been made during the past decade; however, the role of various approximations remains unclear and a unified methodology is lacking. Here, we present and analyse a comprehensive and efficient approach to compute the intrinsic, phonon-limited drift and Hall carrier mobilities of semiconductors, within the framework of the first-principles Boltzmann transport equation. The methodology exploits a novel approach for estimating quadrupole tensors and including them in the electron-phonon interactions, and capitalises on a rigorous and efficient procedure for numerical convergence. The accuracy reached in this work allows to assess common approximations, including the role of exchange and correlation functionals, spin-orbit coupling, pseudopotentials, Wannier interpolation, Brillouin-zone sampling, dipole and quadrupole corrections, and the relaxation-time approximation. A detailed analysis is showcased on ten prototypical semiconductors, namely diamond, silicon, GaAs, 3C-SiC, AlP, GaP, c-BN, AlAs, AlSb, and SrO. By comparing this extensive dataset with available experimental data, we explore the intrinsic nature of phonon-limited carrier transport and magnetotransport phenomena in these compounds. We find that the most accurate calculations predict Hall mobilities up to a factor of two larger than experimental data; this could point to promising experimental improvements in the samples quality, or to the limitations of density-function theory in predicting the carrier effective masses and overscreening the electron-phonon matrix elements. By setting tight standards for reliability and reproducibility, the present work aims to facilitate validation and verification of data and software towards predictive calculations of transport phenomena in semiconductors., Comment: 40 pages and 26 figures

The double-layer Aurivillius phases Pb1-2xBi1.5+2xLa0.5Nb2-xMnxO9 (x = 0, 0.1, 0.3, and 0.5) were synthesized by a molten salt method using a mixture of K2SO4/Na2SO4. The effect of composition on the structure, morphology and dielectric properties was investigated. X-ray diffraction showed that single-phase samples with a non-polar, orthorhombic A21am structure were obtained for x = 0, 0.1 and 0.3. The unit cell becomes more orthorhombic with increasing x as the degree of distortion of the BO6 octahedra in the perovskite layer increases. Raman spectroscopy showed the typical modes of the orthorhombic double-layer Aurivillius structure and indicated that the La3+ ions prefer to occupy the perovskite A-site, Mn3+ occupies the B-site, and the Pb2+ ions are found in the Bi2O2 layer. The morphology of the samples was probed by scanning electron microscopy, which showed anisotropic, plate-like crystallites that increased in size with increasing x. The dielectric constant significantly increased with x, and the ferroelectric properties became more relaxor-like.

Perovskite solar cells have achieved comparable power conversion efficiencies as commercial silicon cells, making the issue of long-term operation stability as the most critical scientific factor toward industrial realization. In this work, we introduce SnS quantum dots (QDs) as a new inorganic hole transporting material (HTM) to perovskite solar cells. The SnS QDs decorated with the oleylamine (OAm), oleic acid (OA), and trioctylphosphine (TOP) ligands are prepared through the traditional nonaqueous solvothermal method. Therefore, the as-synthesized SnS QDs can be orthogonally processed onto the top of a triple cation perovskite film, exhibiting a good surface coverage and an excellent hole extraction ability. With careful device engineering towards film thickness, annealing procedure, and ligand exchange on the SnS layer, we have obtained a power conversion efficiency (PCE) of 13.7%. Compared with the 2,2',7,7'-tetrakis(N,N-di-p-methoxyphenylamine)-9,9'-spirobifluorene (spiro-OMeTAD)-based control device, the SnS-based perovskite solar cell presents a better air stability, showing unaltered device performance after 1000 h storage under ambient conditions.

CdSe semiconductor thin films were grown on indium tin oxide (ITO) coated glass substrates by co-electrochemical deposition method. Deposition potential was kept at - 0.95 V vs. Ag/AgCl reference electrode for ten minutes. Deposition electrolyte includes an aqueous solution of 10 mM CdCl2, 20 mM H(2)SeO(3 )as precursors, 200 mM LiCl as complexing agent, and HCl for adjusting of pH. Deposited CdSe thin film was annealed at 500 degrees C for 30 min in air medium. Precursor and annealed CdSe thin films were characterized using a number of techniques, including SEM, EDX, XRD, UV-vis spectroscopy, and electrochemical impedance spectroscopy. SEM studies show that annealing alters the surface of precursor CdSe film from smooth to granular appearance. According to EDX analyses, the ratio of Cd/Se is close to 1.07 and 1.04 for the precursor and annealed CdSe thin film, respectively. XRD analysis shows that each film has polycrystalline structure. Precursor film has only cubic structure of CdSe, while annealed film has hexagonal structure of CdSe and cubic crystal phase of CdO. Optical energy band gap of the as-deposited CdSe film increases from 1.64 to 1.71 eV after annealing due to the mixture of the two phases. Refractive index against wavelength changes between 2.0 and 3.3. Calculations performed by using the data of Mott-Schottky measurements show that precursor CdSe film has 1.72 x 10(16 )cm(-3), while annealed film is of 3.65 x 10(17 )cm(-3 )carrier concentration. The prepared films exhibit n-type semiconductor character. The study reports energy level diagrams of the produced semiconductor CdSe thin films by using the Mott-Schottky and Tauc's approximations. The carrier transport properties in the interface between active CdSe thin film and electrolyte are discussed based on an equivalent electronic circuit simulated to the Nyquist data of the CdSe/electrolyte system.

Funder: Aziz Foundation, Funder: Downing College, Cambridge, Funder: Isaac Newton Trust; Id: http://dx.doi.org/10.13039/501100004815, Nickel oxide (NiO x ), a p‐type oxide semiconductor, has gained significant attention due to its versatile and tunable properties. It has become one of the critical materials in wide range of electronics applications, including resistive switching random access memory devices and highly sensitive and selective sensor applications. In addition, the wide band gap and high work function, coupled with the low electron affinity, have made NiO x widely used in emerging optoelectronics and p‐n heterojunctions. The properties of NiO x thin films depend strongly on the deposition method and conditions. Efficient implementation of NiO x in next‐generation devices will require controllable growth and processing methods that can tailor the morphological and electronic properties of the material, but which are also compatible with flexible substrates. In this review, we link together the fundamental properties of NiO x with the chemical processing methods that have been developed to grow the material as thin films, and with its application in electronic devices. We focus solely on thin films, rather than NiO x incorporated with one‐dimensional or two‐dimensional materials. This review starts by discussing how the p‐type nature of NiO x arises and how its stoichiometry affects its electronic and magnetic properties. We discuss the chemical deposition techniques for growing NiO x thin films, including chemical vapor deposition, atomic layer deposition, and a selection of solution processing approaches, and present examples of recent progress made in the implementation of NiO x thin films in devices, both on rigid and flexible substrates. Furthermore, we discuss the remaining challenges and limitations in the deposition of device‐quality NiO x thin films with chemical growth methods. image

Compositional engineering of BiFeO3 can significantly boost its photovoltaic performance. Therefore, controlling site substitution and understanding how it affects the optical and electronic properties while achieving robust and stable phases is essential to continue progressing in this field. Here the influence of cation co-substitution in BiFeO3 on phase purity, optical and electronic properties is investigated by means of X-ray diffraction, spectroscopic ellipsometry and X-ray absorption spectroscopy, respectively. Piezoelectric force microscopy and ferroelectric characterization at room temperature has been carried out in co-doped BiFeO3 films. First-principles calculations are also performed and compared to the experimental observations. It is shown that the incorporation of La3+ in Bi(Fe,Co)O3 films improves phase purity and stability while preserving the reduced band gap achieved in metastable Bi(Fe,Co)O3. Moreover, it is suggested that the changes in the optoelectronic properties are mainly dictated by the hybridisation between unoccupied Co 3d and O 2p states along with the presence of Co3+/Co2+ species. This thorough study on (Bi,La)(Fe,Co)O3 thin films coupled with the use of a cost-effective and facile solution deposition synthesis increases the motivation to continue exploiting the potential of these perovskite materials., This research was supported by the Spanish Ministerio de Ciencia, Innovación y Universidades (“Severo Ochoa” Programme for Centres of Excellence in R&D CEX2019-000917-S, MAT2017-83169-R, RTI2018-093996-B-C32, PID2019-107727RB-I00 (AEI/FEDER, EU)). P. M. thanks financial support from FPI fellowship (PRE2018-084618). C. M. and C. C. acknowledge computational resources and technical assistance from the Australian Government and the Government of Western Australia through the National Computational Infrastructure (NCI) and Magnus under the National Computational Merit Allocation Scheme and The Pawsey Supercomputing Centre. The authors acknowledge Prof. J. Fontcuberta for providing access to his experimental facilities and the support of ALBA staff for the successful performance of the measurements at CIRCE beamline of the ALBA Synchrotron Light Source. I. F. and C. C. acknowledge support from the Spanish Ministry of Science, Innovation and Universities under the “Ramón y Cajal” fellowship RYC2017-226531 and RYC2018-024947-I, respectively. M. C and I. F acknowledge Beca Leonardo from fundación BBVA. H. T is financially supported by China Scholarship Council (CSC) with no. 201906050014. The work of P. M. and H. T have been done in the framework of the doctorate in Materials Science of the Autonomous University of Barcelona.

Thermoplastics when they become thermally conductive, have a great potential to be used in thermal management applications due to their low cost, lightweight, and flexibility. Here, synthetic graphite and graphene are used as thermally conductive fillers to fabricate Polyphenylene Sulfide-(PPS) based composite materials with high thermal conductivity. Graphene and graphite added PPS composites were manufactured by using a twin-screw extruder and injection molding machine. Physical, thermal, mechanical, and morphological properties of the composites were investigated by several characterization methods including thermogravimetric analysis, differential scanning calorimetry. thermomechanical analysis, scanning electron microscopy. thermal diffusivity measurement, and tensile and flexural tests, The in-plane and through-plane thermal conductivity coefficient of graphene (5 wt. %) loaded synthetic graphite (40 wt. %)/PPS composites are greatly improved to 26.45 and 5.02 W/mK, respectively compared to that of neat PPS. The outstanding in-plane thermal conductivity of graphene loaded graphite/PPS composites is attributed to the formation of an effective thermal conductive pathway due to the alignment of the layered structure of graphene and graphite fillers in the flow direction., scientific and technological research council of Turkey [117M088], The authors are grateful for the funding from the scientific and technological research council of Turkey (Project no: 117M088).

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease preferentially affecting motoneurones. Transgenic mouse models have been used to investigate the role of abnormal motoneurone excitability in this disease. Whilst an increased excitability has repeatedly been demonstrated in vitro in neonatal and embryonic preparations from SOD1 mouse models, the results from the only studies to record in vivo from spinal motoneurones in adult SOD1 models have produced conflicting findings. Deficits in repetitive firing have been reported in G93A SOD1((high copy number)) mice but not in presymptomatic G127X SOD1 mice despite shorter motoneurone axon initial segments (AISs) in these mice. These discrepancies may be due to the earlier disease onset and prolonged disease progression in G93A SOD1 mice with recordings potentially performed at a later sub-clinical stage of the disease in this mouse. To test this, and to explore how the evolution of excitability changes with symptom onset we performed in vivo intracellular recording and AIS labelling in G127X SOD1 mice immediately after symptom onset. No reductions in repetitive firing were observed showing that this is not a common feature across all ALS models. Immunohistochemistry for the Na+ channel Nav1.6 showed that motoneurone AISs increase in length in G127X SOD1 mice at symptom onset. Consistent with this, the rate of rise of AIS components of antidromic action potentials were significantly faster confirming that this increase in length represents an increase in AIS Na+ channels occurring at symptom onset in this model. (C) 2020 Published by Elsevier Ltd on behalf of IBRO.

Quantum mechanical calculations can clarify the relationship between structure and ultimate optical and electrochemical properties of conjugated polymers and produce a ground for the design of advanced materials for futuristic applications. Herein, we have examined the structural geometries and electronic properties of different monomeric structures with the same electroactive group to provide a relationship between calculated electronic properties of the monomers with the observed optical and electrical properties of their conjugated polymers. For this purpose, three different amide substituted 2,5-di(2-thienyl)-1H-pyrrole compounds containing a different number of electroactive groups have been synthesized and molecular structure optimizations have been carried out with the Density Functional Theory (DFT) calculations. FT-IR and NMR spectra of optimized geometries have been compared with experimental data. Furthermore, electronic properties of the monomeric structures such as chemical hardness/softness, ionization potential, HOMO-LUMO energy levels, electronegativity have been revealed and molecular electrostatic potential (MEP) surface has been calculated to determine the electrophilic and nucleophilic reactive attack regions of the molecules considered in this study. Finally, Total Density of State (TDOS), Partial Density of State (PDOS) and Mulliken charge analyses of these molecules have been carried out. Our calculations based on ab-initio methods for the monomers have been compared with the optical and electrical properties of their conductive polymers in order to understand interrelationship between monomer structure and polymer properties.

Cadmium oxide thin films were prepared with various levels (1%, 3% and 5%) of chromium dopants. Successive ionic layer adsorption and reaction (SILAR) method has been employed to prepare these thin films on glass substrates at room temperature. The changes in morphological, structural, and optical properties of the produced CdO thin films were explored. The effects of Cr doping were studied thoroughly by performing X-ray diffractometer (XRD), scanning electron microscope (SEM), energy dispersive spectroscopy analysis (EDS), ultraviolet–visible spectrometer (Uv–vis), and photoluminescence (PL) spectrometer measurements of the thin films. The XRD measurements show that the samples have the cubic crystal structure. Surface morphologies of the samples are clearly affected by different concentrations of Cr doping. The EDS analysis affirmed the presence of Cr elements in the structure of CdO nanostructures after doping. It was observed that the band gaps calculated using absorption measurements can be manipulated from 2.51 eV to 2.87 eV with varying Cr doping rates in the CdO nanostructures. The PL spectrum displayed that the PL intensity of the CdO nanostructures may also be tuned depending on different concentrations of Cr dopings.

Perovskite oxides such as ferrites have been widely investigated for their remarkable electrochemical activity as SOFC electrodes. However, their phase instability in reducing conditions remains an issue for anode application. The role of Mn substitution into B-site of La0.6Sr0.4FeO3-δ (LSF) perovskite oxide was investigated. New insights on the structural evolution of La0.6Sr0.4Fe0.8Mn0.2O3-δ (LSFMn) upon high temperature reduction were revealed. In oxidizing atmosphere, Mn substitution reduces the oxygen vacancy concentration while, switching to reducing conditions, it drives the transition from rhombohedral perovskite to single Ruddlesden-Popper phase, affecting the Fe0 exsolution. Redox-cycles of LSFMn were investigated and the properties of re-oxidized compounds were highlighted. The effect of Mn substitution on perovskite conductivity was also evaluated both in oxidizing and reducing conditions.

A single-phase sample of the Aurivillius compound Pb0.4Bi2.1La0.5Nb1.7Mn0.3O9 was prepared by a molten salt method using K2SO4/Na2SO4 as the flux. The crystal structure, morphology, ferroelectric, and magnetic properties were investigated. Neutron powder diffraction data confirmed a non-centrosymmetric orthorhombic crystal structure with space group A21am and Pb/Bi disorder in the bismuth oxide blocks, Bi/Pb/La disorder on the perovskite A-site, and Nb/Mn disorder on the perovskite B-site. The morphology of the sample showed anisotropic plate-like grains as probed by scanning electron microscopy. The dielectric constant exhibits a transition peak between 600 K and 640 K that depends on frequency, indicating relaxor ferroelectric behavior. Electrical polarization versus applied field loops are unsaturated, with a remnant polarization of 0.43 μC/cm2 at 40 Hz under the maximum electrical field applied of 160 kV/cm. The ferroelectricity originates from the displacement of oxygen atoms in the BO6 octahedra, resulting in a polar structural distortion. Magnetic susceptibility measurements showed the presence of mixed Mn3+ and Mn4+, resulting in short-range ferromagnetic order via double exchange interactions below 33 K. The remnant magnetization (Mr) is 0.01 emu/g at 5 K. This mixed valence of Mn cations is mainly responsible for the high electrical conductivity. Thus, Pb0.4Bi2.1La0.5Nb1.7Mn0.3O9 exhibits coexisting ferroelectric and ferromagnetic properties.

In this review article, we are going to present an overview on possible applications of light-addressable electrodes (LAE) as actuator/manipulation devices besides classical electrode structures. For LAEs, the electrode material consists of a semiconductor. Illumination with a light source with the appropiate wavelength leads to the generation of electron-hole pairs which can be utilized for further photoelectrochemical reaction. Due to recent progress in light-projection technologies, highly dynamic and flexible illumination patterns can be generated, opening new possibilities for light-addressable electrodes. A short introduction on semiconductor-electrolyte interfaces with light stimulation is given together with electrode-design approaches. Towards applications, the stimulation of cells with different electrode materials and fabrication designs is explained, followed by analyte-manipulation strategies and spatially resolved photoelectrochemical deposition of different material types. ispartof: SENSORS vol:20 issue:6 ispartof: location:Switzerland status: published

[EN] The metastability impediment which usually prevents the obtaining of a phase-pure BiFeO3 material can be dramatically stressed when taking the system to the thin film configuration. In order to preserve the stoichiometry, the films need to be processed at low temperatures and hence the solid-state diffusion processes which usually govern the microstructural evolution in bulk cannot be expected to also rule the development of the functional films. All these circumstances were presumed when exploring the possibilities of an aqueous solution–gel process plus spin-coating deposition method to reproduce, in thin film dimensions, the excellent multiferroic properties that have been previously observed with an optimized rare-earth and Ti4+-codoped BiFeO3 bulk composition. The experiments indicate high reliability for the tested methodology, allowing for the obtaining of homogeneous dense films at temperatures as low as 600 1C and with a tunable multiferroic response depending on the formulated rare-earth (Sm or Nd). Thorough structural characterization of the films reveals that despite the low temperature processing restrictions, effective microstructural control is achieved at the nanoscale, which is attributed to effective retention (pinning) of the dopants inside the perovskite structure of BiFeO3., his work was supported by the Spanish Ministry of Science, Innovation and Universities (MICINN) under projects MAT2016-80182-R, MAT2017-87134-c2-2-R and partially by the project MAT2016-76851-R. It was also supported by the Research Foundation Flanders (FWO-Vlaanderen), project number G039414N. Dr T. Jardiel acknowledges the European Science Foundation (ESF) and the Ramon y Cajal Program of MICINN for the financial support. Work by Dr Calatayud was also supported by Fundación General CSIC (COMFUTURO Program). We acknowledge support of the publication fee by the CSIC Open Access Publication Support Initiative through its Unit of Information Resources for Research (URICI).

Herein, pure and cobalt (Co) doped cadmium oxide (CdO) thin films successfully deposited onto glass slides by successive ionic layer adsorption and reaction (SILAR) method. And, the structural, morphological, optical, and electrical properties were studied by employing X-ray diffraction (XRD), field emission scanning electron microscope (FE-SEM), Energy dispersive X-ray analysis (EDAX), Ultraviolet-visible spectroscopy (Uv-vis), Photoluminescence (PL) spectrum, I-V measurements for the produced samples. The XRD analysis uncovered that the CdO films exhibited cubic phase of cadmium oxide with the preferred orientation (111) plane. And, it showed that Co atoms successfully incorporated into the CdO lattices as no secondary phases were detected in the XRD spectra. The FE-SEM images displayed that the introduced impurities modified the surface morphologies. The EDAX analysis definitely proved the presence of the aimed materials (Cd, O, and Co) on the SILAR grown samples. The Uv-vis spectroscopy showed that optical energy bandgap enhanced from 2.5 eV to 2.93 eV as CdO nanostructures (NSs) doped with the different Co doping concentrations. The PL spectrum revealed that the luminescence characteristics of produced films were evidently influenced by the Co doping in the CdO NSs. Also, the resistivity of the produced samples was found to be decreased by the help of the I-V measurements.

The nature of polaron formation has profound implications on the transport of charge carriers in conjugated polymers, but still remains poorly understood. Here we develop in situ electrochemical resonant Raman spectroscopy, a powerful structural probe that allows direct observation of polaron formation. We report that polaron formation in ordered poly(3-hexyl)thiophene (P3HT) polymer domains (crystalline phase) results in less pronounced changes in molecular conformation, indicating smaller lattice relaxation, compared to polarons generated in disordered polymer domains (amorphous phase) for which we observe large molecular conformational changes. These conformational changes are directly related to the effective conjugation length of the polymer. Furthermore, we elucidate how blending the P3HT polymer with phenyl C-61 butyric acid methyl ester (PCBM) affects polaron formation in the polymer. We find that blending disturbs polymer crystallinity, reducing the density of polarons that can form upon charge injection at the same potential, whilst the lost capacity is partly restored during post-deposition thermal annealing. Our study provides direct spectroscopic evidence for a lower degree of lattice reorganisation in crystalline (and therefore more planarised) polymers than in conformationally disordered polymers. This observation is consistent with higher charge carrier mobility and better device performance commonly found in crystalline polymer materials.

The composite of samarium doped ceria (Sm0.2Ce0.8O2-delta, SDC) and co-doped barium cerate (BaZr0.1Ce0.7Y0.1Yb0.1O3-delta, BZCYYb) is prepared by mechanical mixing and investigated as electrolyte for intermediate temperature solid oxide fuel cells (IT-SOFCs). Coexistence of SDC and BZCYYb are observed for composite electrolyte by X-ray diffraction after sintering at 1500 degrees C for 5 h, while the slight deviation of the diffraction peak indicating the element diffusion between two phases. The scanning electron microscope and electron probe microanalyzer results demonstrate that small BZCYYb grains disperse uniformly around the grains of SDC, limiting the growth of SDC grains and decreasing the average grain size of composite electrolyte. Impedance spectroscopy measurement reveals that the grain boundary resistance can be significantly reduced by about an order of magnitude through adding 15-30 wt. % BZCYYb to SDC. Single cells based on the composite electrolyte are fabricated using nickel cermet (Ni-SDC) anode and perovskite (La0.6Sr0.4Co0.2Fe0.8O3-delta, LSCF) cathode., Relatively high open circuit voltage (OCV), much lower polarization resistance and encouraging high power density are obtained for cells with composite electrolyte compared to those with single SDC electrolyte. Among all of the samples, single cell based on 15 wt. % BZCYYb-85 wt. % SDC composite electrolyte exhibits the lowest total resistances of 0.641 Omega.cm(2) and the highest peak power densities of 0.56 W. cm(-2) at 600 degrees C. (C) 2018 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

Room temperature multiferroism with enhanced ferro and piezoelectric properties of a new lead-free MnO2 added 0.90(Li0.12Na0.88NbO3)-0.10BaTiO(3) ceramic is reported. The addition of MnO2 as an additive resulted in a two fold increase in remnant polarization (P-r) (from similar to 7.30 to 17.20 mu C/cm(2)), similar to 50% increase in large-signal piezoelectric coefficient (d(33)(center dot)) (from similar to 117 to176 pm/V) and symmetric butterfly loop are observed. Phase analysis revealed that MnO2 entered the host lattice as Mn2+ and Mn4+-ions and induced room temperature ferromagnetic-like character. Interestingly, an intrinsic coupling between the two ferroic orders is evidenced by the observation of a magneto-electric voltage coefficient (etE) of similar to 0.94 mV/cm.Oe. (C) 2018 Acta Materialia Inc Published by Elsevier Ltd. All rights reserved.