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The wide bandgap oxide semiconductor thin films are synthesized using tetrahydroxogallate (III) ammonium {NH4Ga(OH)4} precursor at a concentration of 10 at% Ga and varying amounts of hydrated aluminum nitrate between 0.6 and 3.2 at%. Thin films of β‐Ga2O3:Al are synthesized by spin coating and spray pyrolysis with postannealing in nitrogen ambient at 930 °C. The structural properties of the thin films are investigated using XRD and Raman spectroscopy, while the electrical characteristics are determined using 4‐point probe, current–voltage (I–V), and capacitance–voltage (C–V) measurements with Ti/Al/Ni/Au Ohmic contacts and Pd/Au Schottky contacts. The β‐Ga2O3 with 2.2 at% Al is found to be the optimal concentration in this study, resulting in ideality factors of 1.10 and 1.09, saturation currents of 3.17 × 10−6 and 3.10 × 10−6 A, Schottky barrier heights of 0.73 and 0.88 eV, and series resistances of 948 and 955 Ω, for the spin‐coated and pyrolytically sprayed samples respectively. [ABSTRACT FROM AUTHOR]

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We use a combination of density functional theory (DFT) and dynamical mean field theory (DMFT) to unveil orbital field-induced electronic structure reconstruction of the atomic Sn layer deposited onto a Si(111) surface (Sn/Si(111)− 3 × 3 R 30 ∘ ), also referred to as α -Sn. Our DFT + DMFT results indicate that α -Sn is an ideal testing ground to explore electric field-driven orbital selectivity and Mott memory behavior, all arising from the close proximity of α -Sn to metal insulator transitions. We discuss the relevance of orbital phase changes for α -Sn in the context of the current–voltage ( I − V ) characteristic for future silicon-based metal semiconductor atomristors. [ABSTRACT FROM AUTHOR]

Herein, p‐type flexible and transparent electrodes of Cu2–xSe are produced at different conversion times at 20, 25, and 30 s of polyester/Cu thin films via chemical bath deposition. To study the charge transport properties across the Cu2–xSe layer, the organic light‐emitting diodes (OLEDs) are produced according to the following configuration: polyester/Cu2–xSe/poly(3,4‐ethylenedioxythiophene):poly(styrene sulfonate)/poly[2‐methoxy‐5‐(2‐ethylhexyloxy)‐1,4‐phenylenevinylene]/aluminum (polyester/Cu2–xSe/PEDOT:PSS/MEH‐PPV/Al), resulting in a direct tunneling in the transport of holes. The control of the barrier's energy between the Cu2–xSe electrode and the MEH‐PPV polymer allows it to tune selectively of the OLED’ charge transport mechanism. The morphological analysis of the Cu2–xSe electrode, carried out using atomic force microscopy, as well as the temperature dependence of the current–voltage measurements in the OLED (50–300 K) shows the ideal deposition time in the chemical bath. In contrast, impedance spectroscopy results confirm the inexistence of the Cu2–xSe/PEDOT:PSS interface using 30 s to Cu2–xSe synthesis. As a result, the control of the injection mechanism of charges can be obtained by reducing the barrier energy to hole transport during the synthesis process of the Cu2–xSe layer via chemical bath deposition, thus simplifying and reducing the costs of the device's processing. [ABSTRACT FROM AUTHOR]

Inter-granular Sn particles affect transport and magnetic properties both in the normal and superconducting states of polycrystalline GdBa2Cu3O7−δ (GdBCO) superconductors drastically. Normal state resistivity at 300 K increases ~ 18.0 times as the concentration of Sn is increased. An unusual upturn in resistivity as a function of temperature curve with a dip is observed in GdBCO with 3.0 wt% of Sn in which suppression of superconducting phase transition has been observed. Current-voltage (IV) curves below Tc exhibit nonlinear features in composites of GdBCO and Sn. Magnetization (M) as a function of magnetic field (H) curves at 2.0 –20.0 K in GdBCO shifts strongly with the addition of 1.0 wt% Sn. We have extracted irreversible magnetization, lower critical field (Hc1) and magnetic critical density (Jcm) as a function of H at several T. The maximum pinning force density is 0.4 GN/m3 in GdBCO which is reduced in the Sn added GdBCO. [ABSTRACT FROM AUTHOR]

Copper oxide (CuO) is a nanostructured semiconductor material with the potential for solar energy conversion and can be suitable for solar cells when used as a thin film. Herein, nondoped and doped (doping ratios of 1%, 2%, and 3% zirconium [Zr]) CuO thin films on silicon (Si) with the spin‐coating technique are developed. Optical and topological characterizations of CuO thin films are examined by ultraviolet‐visible and X‐ray diffraction. The electrical properties of nondoped and Zr‐doped CuO/Si heterojunctions are investigated with experimental current–voltage measurements in the dark and under illuminated conditions. The electrical behavior of nondoped and Zr‐doped CuO/Si heterojunctions is obtained using the experimental J–V technique and computational Cheung–Cheung and Norde methods. A simulation based on nondoped and Zr‐doped CuO/n‐Si heterojunction solar cells using SCAPS‐1D is completed. Photovoltaic (PV) parameters of experimentally produced and theoretically calculated CuO and Zr‐doped CuO/Si heterojunction solar cells are compared. Accordingly, PV parameters of 1% Zr‐doped CuO/Si solar cells show the highest power conversion efficiency calculated as a function of interfacial defect density and hole carrier concentration. [ABSTRACT FROM AUTHOR]

In this paper, firstly, a new organic material 9 containing triphenylamine (TPA) unit as an electron donor and diaminomaleonitrile (DAMN) unit as an electron acceptor and thiophene scaffold as a π‐linker bridge was designed for diode applications according to D‐π‐A architecture. The organic material 9 was synthesized in four reaction steps with excellent yield (94 %), and fully characterized by 1H NMR, 13C NMR, FTIR, and HRMS spectra. The diode performance properties of the obtained organic material were examined in detail. Current‐voltage (I–V) and capacitance‐voltage (C–V) measurements of this diode were carried out. As a result of the analysis of these measurements, the effect of the organic material used as the interface material on the electrical properties of the diode was analyzed. [ABSTRACT FROM AUTHOR]

In the recent research we compared the solar energy performance of photogalvanic cell (PG cell) for two food dyes that act as photosensitizer tatrazine and sunset yellow in the DSS-EDTA (Dioctyl sodium sulphosuccinate-Ethylenediamine tetraacetic acid) system for power generation and its storage. Both are azo food dyes and act as photosensitizer, DSS acts as an anionic Surfactant and EDTA act as a reductant. The electrical parameters of both dye systems were studied and compared. The observed conversion efficiencies and fill factor for both systems in the DSS-EDTA system were 0.6163%, 0.2800, and 1.2186%, 0.2900, respectively. The stable photopotential (Voc) was 879 mV and 864.0 mV whereas the stable photocurrent (isc) was 220 µA and 390 µA, respectively. In addition to having built-in storage capacity, the photogalvanic cell can operate in dark conditions. The amount of time required for the cell to reach half the value of power at power point, which was measure its performance called t1/2 of the cell. Cell performance of both PG cell was determined and for the Tartrazine-EDTA-DSS system it has been obtained 100 min while for the sunset yellow-EDTA-DSS system it was observed at 140 minutes. The current-voltage (i-v) characteristics of both the systems have been studied. [ABSTRACT FROM AUTHOR]

Our study examined how native oxide layers, InN and InSb, affected the current-voltage and capacitance-voltage characteristics of the Au/n-InP Schottky diode at a temperature of 300 K with and without interface states, traps, and tunneling current. The simulation was carried out using the Atlas-Silvaco-Tcad device simulator. From our results, we found that the effective barrier heights were measured to be 0.474 eV, 0.544 eV, and 0.561 eV via I-V measurements and 0.675 eV, 0.817 eV, and 0.80 eV via C-V measurements. Additionally, we utilized the high-low frequency method to calculate the average density of interface state density, which was determined to be approximately 6.03 . 1011 and 3.33 . 1012 сm – 2 . eV – 1. The results indicate that a thin film of InN and InSb can effectively passivate the InP surface, as evidenced by the good performance of the passivized sample. [ABSTRACT FROM AUTHOR]

An exponent (η ) revealing the Berezinskii-Kosterlitz-Thouless (BKT) transition has been extracted from the nonlinear IV characteristics in Nd x Ca 0.3 Ce y Ba 2 Cu 3 O 7 - δ (NCCBCO) superconductors with (x, y) = (0.6, 0.1), (0.55, 0.15) and (0.5, 0.2) in the zero magnetic field. The onset of the BKT phase transition temperature, T BKT , has been identified from the nonlinear to linear transformation of current-voltage (IV) characteristics. Superfluid phase stiffness (SPS), J S , is extracted from the BKT exponent. Sharp discontinuous jump of SPS, J S at T BKT , disappears in the bulk 3D cuprate system. SPS, J S , vanishes at T BKT corresponding to η = 1.0. The intersection between J S (T) and the BKT line is not visible in 3D cuprate superconductors. However, an incomplete BKT phase transition observed in 3D cuprate systems is found to be a second-order transition induced by coupling between 2D superconducting layers in which BKT vortices are formed. [ABSTRACT FROM AUTHOR]

We use a combination of density functional theory (DFT) and dynamical mean field theory (DMFT) to unveil orbital field-induced electronic structure reconstruction of the atomic Sn layer deposited onto a Si(111) surface (Sn/Si(111)−3×3R30∘), also referred to as α-Sn. Our DFT + DMFT results indicate that α-Sn is an ideal testing ground to explore electric field-driven orbital selectivity and Mott memory behavior, all arising from the close proximity of α-Sn to metal insulator transitions. We discuss the relevance of orbital phase changes for α-Sn in the context of the current–voltage (I−V) characteristic for future silicon-based metal semiconductor atomristors.

The effects of Fe-implantation on the electrical characteristics of Au/p-Si Schottky barrier diodes (SBDs) were studied using current–voltage (I–V) and capacitance–voltage (C–V) techniques. The Rutherford Backscattering Spectrometry (RBS) and Energy Dispersive Spectroscopy (EDS) results showed that Fe ions are well implanted and present in the Fe-implanted Si material. The acquired results from I–V and C–V analysis showed that the diodes were well fabricated, and Fe-implantation changed the normal diode’s I–V behaviour from typical exponential to ohmic. The ohmic behaviour was described in terms of the defect levels induced by Fe in the middle of the band gap of Si. The conduction mechanism for both forward and reverse currents was presented, and the effect of Fe-implantation on the conduction mechanisms was investigated. The C–V results show that Fe generates a high density of minority carriers in p-Si, which agreed with the increase in reverse current observed in the I–V results. The diode parameters in terms of saturation current, ideality factor, Schottky barrier height, doping density, and space charge region (SCR) width were used to investigate the effect of Fe in p-Si based diode. Owing to the observed changes, which were analogous to those induced by dopants that improve the radiation hardness of silicon, it was safe to say that Fe can also assist in the quest to improve the radiation hardness of silicon using the defect-engineering method.

In this work, we report the fabrication and characterization of a Schottky diode containing a metal–semiconductor Schottky junction. The metal–semiconductor Schottky contact was formed using nickel (Ni) as the metal and silicon carbide (4H-SiC) as the semiconducting material. The metal–semiconductor Schottky diode array was fabricated on 350-μm-thick 4H-SiC (0001) substrates. The Schottky contact was formed using Ni, and a triple layer of Ti/Pt/Au was used for the ohmic contact. Deposition of Ni-Cr alloy on 4H-SiC was carried out to improve the adhesion at the metal–semiconductor interface. Based on the current–voltage (I–V) characteristics, the device output parameter values for turn-on voltage, forward current at 5 V, reverse saturation current, barrier height (φB) and ideality factor (η) were 1 V, 2.57 mA, 652 nA, 0.935 eV and 1.296, respectively. A band diagram is proposed to explain the charge transport phenomena. [ABSTRACT FROM AUTHOR]

Both the transport critical current density at the zero magnetic field and magnetic critical current density in a composite system consisting of bulk YBCO superconductor and insulating BaTiO3 (BTO) have been studied using current–voltage (IV) and magnetization (M) as a function of magnetic field (H), respectively. Vortex pinning by insulating nanoparticles of BTO from the inter-granular network is investigated up to the magnetic field of 7.0 T. By analyzing magnetic critical current density the possibility of crossover from collective pinning (CP) to strong pinning (SP) and how it is affected by BTO have been explored based on the framework of Larkin–Ovchinnikov (LO) theory. Possible scenario of the strong pinning (SP) induced by insulating nanoparticles has also been studied using an exponent. [ABSTRACT FROM AUTHOR]

Porous Ni-doped copper oxide (NCO) photocatalyst has been produced using chemical activation and metal doping techniques. Structural, optical, morphological, and electrical analyses were performed on copper oxide (CO) and porous NCO photocatalysts. The monoclinic-phased, UV/Vis light-triggered, electrically conductive, and porous-surfaced NCO photocatalyst was successfully synthesized, according to a detailed physicochemical investigation. The photo-decomposition abilities of synthetic porous NCO and counterpart CO photocatalysts were investigated and compared using Allura red (AR). According to the photocatalytic study, the porous NCO photocatalyst outperformed its counterpart (CuO) and eliminated 91.4% (adsorption: 18%; decomposition: 79%) of the AR dye in 48 min. Over the porous NCO photocatalyst, the AR dye disintegrated at a rate of 0.024 min−1, which is more than 1.84 times quicker than the rate of disintegration over the CO photocatalyst. The porous NCO photocatalyst, as synthesized, preserved 88% of its photocatalytic activity after five recyclability tests and had remarkable electron-hole separation activity, according to reusability tests and transient-photocurrent measurements. Also, the radical capture experiment suggested that superoxide and hydroxyl are important for porous NCO's photocatalytic activity. According to the findings of this research, the synthesis of ferromagnetic metal-doped and porous semiconductive materials has a great potential for azo dye breakdown, which makes it an efficient, cost-effective, and environmentally acceptable solution for the clean-up of polluted water. [Display omitted] [ABSTRACT FROM AUTHOR]

Herein, we employed the sol–gel technique to synthesize Cu2O-based nanocrystals with Co and Na doping and co-doping, respectively. A correlation was established among several characterizations of cuprous oxide-based nanocrystals to observe their feasibility in the field of energy materials. Raman spectra typically show the formation of Cu2O, whereas, in the case of Na co-doping, it exhibits the partial presence of CuO. This form of the results prompts the conductivity of nanocrystal samples to be enhanced. According to the current–voltage measurement, the current response slightly increases as doping and co-doping concentrations rise, in which Na5% co-doped Cu2O:Co shows the optimum. Photoluminescence (PL) lifetime measurement shows increases in relative PL lifetime intensity caused by Na doping, which may be attributed to oxygen vacancies. Moreover, it is observed from the cyclic voltammetry (CV) profile that the Na and Co-doped concentration significantly enhances energy storage capability. The electrode using Na5%Cu2O:Co has shown capacitive retention of 69% after 500 GCD cycles @ 10 A g–1. This indicates the practical applicability of these developed cuprous oxide-based nanocrystals as electrode materials for improved electrochemical property. Eventually, the charge–discharge was performed at different current densities, in which specific capacitance was consistent with the CV result. [ABSTRACT FROM AUTHOR]

The effects of Fe-implantation on the electrical characteristics of Au/p-Si Schottky barrier diodes (SBDs) were studied using current–voltage (I–V) and capacitance–voltage (C–V) techniques. The Rutherford Backscattering Spectrometry (RBS) and Energy Dispersive Spectroscopy (EDS) results showed that Fe ions are well implanted and present in the Fe-implanted Si material. The acquired results from I–V and C–V analysis showed that the diodes were well fabricated, and Fe-implantation changed the normal diode's I–V behaviour from typical exponential to ohmic. The ohmic behaviour was described in terms of the defect levels induced by Fe in the middle of the band gap of Si. The conduction mechanism for both forward and reverse currents was presented, and the effect of Fe-implantation on the conduction mechanisms was investigated. The C–V results show that Fe generates a high density of minority carriers in p-Si, which agreed with the increase in reverse current observed in the I–V results. The diode parameters in terms of saturation current, ideality factor, Schottky barrier height, doping density, and space charge region (SCR) width were used to investigate the effect of Fe in p-Si based diode. Owing to the observed changes, which were analogous to those induced by dopants that improve the radiation hardness of silicon, it was safe to say that Fe can also assist in the quest to improve the radiation hardness of silicon using the defect-engineering method. [ABSTRACT FROM AUTHOR]

Four natural dyes were extracted from different fruits used in the Dye-sensitized solar cell (DSSC). It includes ber, blackberry, black grapes, and blueberry by individual dye or combined with other dyes. The dye solution's absorption spectra were extended to the whole visible region 200–750 nm. FTIR spectroscopy was employed to identify the possible functional group vibrations responsible for the dyes' chemical activity and optical behaviour. The TiO2 powder was coated on the ITO conducting surface to form a thin film. The experimental results showed that the ber dye produces the highest solar cell efficiency (η), ˜13%, among all four extracted anthocyanin studied. It also found that ber combination with other dyes is higher conversion efficiency than blackberry, black grapes, and blueberry with another and vice versa. Ber dye can be helpful in the development of more eco-friendly and cost-effective solar cells with commercially promising DSSC.

The present work reports the fabrication of three different ohmic contacts (platinum (Pt)/CuO, gold (Au)/CuO, and silver (Ag)/CuO). Structural properties of the films measured by X-ray diffraction and Raman techniques confirmed that the Cu2O films prepared by DC sputtering using air as a reactive gas, transformed into pure CuO films after thermal annealing. The band gap of the CuO films of 1.33 eV was estimated by reflectance measurements. Hall measurements confirmed the p-type conductivity of the CuO films with an acceptor concentration of 2.04x1016 cm−3.The linear behavior in both directions of polarization observed in the current–voltage measurements confirmed the formation of ohmic contacts between the characterized three metals and CuO. Based on the slope of the current–voltage curve, the best ohmic contact was that fabricated between Au and CuO. The mechanism governing the transport through the interface between the metal/CuO ohmic contact was thermionic emission.

Current-voltage (IV) characteristics of superconducting Eu 1 - x - y Ca x Ce y Ba 2 Cu 3 O 7 - δ (ECCBCO) exhibit nonlinear behaviour below T c irrespective of the nature of doping. Superfluid phase stiffness (SPS) has been extracted by using nonlinear IV and the Ambegaokar-Halperin-Nelson-Siggia (AHNS) theory. Nature of the growth of the superfluid density in co-doped superconducting systems remains differently increasing below T BKT . Possibility of the collapsing of IV within the framework of the Fisher, Fisher and Huse (FFH) formulation around T BKT has been explored. Variations of the static exponent (ν ) and dynamic exponents (z) with T have been studied. [ABSTRACT FROM AUTHOR]

Non-equilibrium Green’s function (NEGF) is a popular method for simulation and modelling of non-equilibrium electron quantum ballistic transport in open mesoscopic system, which is double-gate (DG) nano-MOSFET in this paper, with self-energy scattering effects. In this paper, on-line device simulator nanoMOS using NEGF with finite difference method (FDM) discretization is used to obtain current-voltage (I-V) graph. The simulated on-state current is compared with the calculated and plotted using freeware Scilab code without including NEGF with FDM method to demonstrate the flexibility and accuracy of NEGF with FDM method. Accuracy of 92% is achieved. The difference in due to output resistance at saturation region of I-V curve. Also, this quantum transport model is compared with two others electron transport models derived through Boltzmann statistics along with Einstein relationship, one with high drain bias while other with traditional MOSFET model with ballistic mobility. After analysis, these two approximated equations show 0.87 and 8.8 times, respectively, matches against simulated value. Obviously, nano-MOSFET under high drain bias is closely matched with the quantum model. The traditional MOSFET with ballistic mobility is suitable for very-short-channel length devices (like DG nano-MOSFET) and III-V channel materials with very high-real mobility devices.

A change in current-voltage (I-V) behaviour of the p-Si-based diodes as a result of 4 MeV proton-irradiation to the fluence of 1016 p/cm−2 was investigated using I-V techniques at room temperature. The diode I-V behaviour changed from normal exponential to ohmic behaviour after proton-irradiation, indicating that proton introduce generation-recombination (g-r) centres, defect levels that are positioned in the middle of the band gap of Si. These centres recombine mobile charge carriers, thereby, reducing the concentration of carriers through the space charge region (SCR). The reduction of the concentration results in an increase in material resistivity as confirmed by the increase in series resistance after proton-irradiation. Furthermore, a change in diode parameters such as saturation current (Is), ideality factor (η), Schottky barrier height (ϕb), and series resistance (Rs) due to the irradiation is also investigated. A change in diode parameters and conduction mechanism due to proton-irradiation presented in this work is of great importance for an ongoing study on radiation-induced damages and radiation-hardness of Si material. [ABSTRACT FROM AUTHOR]

We report an analysis of the current-voltage characteristics of a dual-band HgCdTe infrared detector built in an n-p-n configuration and designed for sequential mode operation in mid-wavelength (MW) and long-wavelength (LW) bands. The model treats the device as a pair of back-to-back p-n junctions and addresses both dark and illuminated conditions over a range of temperatures. We show that the assumption of ideal diode behavior (diffusion-only current) provides a very good first approximation, particularly at small bias voltages. We also find that a plot of the resistance-area product RA is the most sensitive indicator of the deviation from ideality, most of which is due to non-diffusion currents in the LW junction. We determine the apportionment of the applied voltage between the two junctions and show that for LW detection, less than half the total voltage appears across the reverse biased LW junction. Our approach should be useful in analyzing other dual-band test data and guiding design improvements. [ABSTRACT FROM AUTHOR]

• The optimal stepped band gap profile is obtained by stacking three CIGS layers with different gallium contents, ranked in ascending order, the lowest gallium content being that of the CIGS layer bordering the buffer layer. • The stepped band gap profile of the absorber layer improves the spectral response of the CIGS-based solar cell. • The internal quasi-electrics fields caused by the stacking of CIGS layers with different band gap improve the collection minority carriers and reduce recombination losses. • Record efficiency of 28.03% was achieved, with a fill factor of 86.42%. In this paper, we investigate a way to improve the performance of thin films CIGS-based solar cells by optimizing their spectral responses. Band gap profile grading, aroused this last decade as a very promising strategy to achieve higher efficiency. This work was performed on a CIGS-based thin-film solar cell model, using cadmium sulphide CdS as a buffer layer, with zinc oxide ZnO as window layer. Focusing on electrical properties such as band gap and electron susceptibility, we modified gallium content of the absorber layer of a reference cell. Using aforementioned band gap grading strategy, we stacked three CIGS layers with different gallium contents, and we modelled a stepped band gap profile using SCAPS-1D. The comparative analysis of the results obtained through numerical simulation, with those of six different band gap profiles of the absorber layer, supports the statement that, stepped band gap profile is a promising approach for engineering improvement of high-efficiency CIGS-based solar cells. In fact, the absorption spectrum of the optimized cell has improved compared to the other band gap profiles simulated in this work; with a peak external quantum efficiency (EQE) of 94%. Efficiencies losses dues to recombination were reduced and the generated photocurrent is higher than that of classical profiles. Record efficiency of 28.03% was achieved with a fill factor of 86.42%. We believe absorber layer stacked in a stepped band gap profile, as a complementary approach to improve performances, is definitely a must-have technology for all future generations high efficiency thin films solar cells. [ABSTRACT FROM AUTHOR]

Junction resistance (RN) as a function of temperature (T) in bulk superconducting NdBa2Cu3O7-δ (NBCO) has been determined following the de Gennes (dG) and Ambegaokar–Baratoff (AB) theories. A convergence of RN (T) obtained by two theories is not impossible at a T which is below the critical temperature. Variation of RN (T) corresponding to the intergranular region is very sensitive to the T-dependence of the gap function (Δ). Moderate range of RN reveals that the junctions are SNS in nature. Within the framework of the dG theory, the influence of the correlation length (ξN) on RN has also been investigated. Also, a moderate junction resistance and nonlinear current–voltage (IV) together reveal that a resistive bulk pinning network may be existing near the superconducting phase transition region. [ABSTRACT FROM AUTHOR]

[Display omitted] • The Cu 2 O materials doped with Na and Co were synthesized using the traditional sol–gel technique. • Annealing resulted in improved electrochemical performance. • Annealing leads to increase in oxygen vacancies. • Doped and codoped samples annealed at 800 °C exhibit excellent electrochemical performance, as assessed by CV and GCD measurements. • XPS spectra clearly indicate the presence of dopants Co and Na. The Na and Co doped Cu 2 O were synthesized by the sol–gel method and annealed at different temperatures under ambient conditions. This study systematically investigated the impact of annealing on the structural, optical, and electrochemical characteristics. The X-ray diffraction pattern reveals the formation of Cu 2 O with a partial presence of CuO. After the annealing process, the majority of the phases underwent a conversion to CuO, along with a partial amount of Cu 2 O, Cu(OH) 2 , and Cu, as determined by XRD and Raman analysis. The current–voltage relationship revealed an increase in conductivity, which was associated with oxygen vacancy, as the annealing temperature rose. The material's band gap was found to be suitable for its application in optoelectronic devices. Additionally, the specific capacitance gradually increased with the rise in annealing temperature. The electrode using Na and Co-doped Cu 2 O annealed at 800 °C (Cu-800) showed a capacitive retention of 80.1 % after 500 cycles. The particle size, pore size, and specific surface area were examined using FESEM and BET characterization, respectively. The XPS spectra clearly indicated the presence of copper and cobalt with multiple oxidation states and sodium with single oxidation states. Finally, the photoluminescence (PL) spectra showed an increase in oxygen vacancies with the incorporation of annealing temperature, which is an important attribute for the material's suitability for photoenergy conversion and energy storage applications. [ABSTRACT FROM AUTHOR]

Fabrication of nanostructured electro-active materials with an ordered organization improved the overall performance of supercapacitor devices (SCDs). In this spirit, we developed Cu(OH) 2 nano-flakes that were statistically ordered to resemble flowers. To increase the specific capacitance and kinetics of the electroactive sample, we employed ultra-sonication to fabricate a Cu(OH) 2 nanocomposite with conductive and capacitive carbon nanotubes (CNTs). The textural and functional group analyses of the wet-chemically produced samples were completed using the XRD and FTIR techniques. I–V, FESEM, and EDX measurements Analyses of pure Cu(OH) 2 and its CNT-based nanocomposites were conducted to evaluate the materials' electrical conductivity, morphology, and chemistry, respectively. The electrochemical characteristics of the as-prepared material's electrodes were investigated, and the CNT-based nanocomposite electrode demonstrated an outstanding specific capacity (Csp) and a promising rate of performance. Our CNT-based nanocomposite had a Cs of 733 Fg-1 at 1 Ag-1 and dropped 8.7% after 4 × 103 cycles. The higher electrochemical properties of the nanocomposite are governed by the nano-flakes-like architecture of the Cu (OH) 2 and the more conductive CNT matrix. According to the obtained findings, our manufactured Cu(OH) 2 /CNT based electrode has great promise for practical applications in next-generation supercapacitor, which are known to be very efficient. [Display omitted] [ABSTRACT FROM AUTHOR]

AlGaN/GaN/Si HEMTs have been investigated using current-voltage-temperature and CDLTS measurements. As has been found from current voltage measurements, parasitic effects were revealed indicating the presence of traps in HEMT device. As a result, the origins of traps are determined from CDLTS experiments. [ABSTRACT FROM AUTHOR]

Four natural dyes were extracted from different fruits used in the Dye-sensitized solar cell (DSSC). It includes ber, blackberry, black grapes, and blueberry by individual dye or combined with other dyes. The dye solution's absorption spectra were extended to the whole visible region 200–750 nm. FTIR spectroscopy was employed to identify the possible functional group vibrations responsible for the dyes' chemical activity and optical behaviour. The TiO2 powder was coated on the ITO conducting surface to form a thin film. The experimental results showed that the ber dye produces the highest solar cell efficiency (η), ˜13%, among all four extracted anthocyanin studied. It also found that ber combination with other dyes is higher conversion efficiency than blackberry, black grapes, and blueberry with another and vice versa. Ber dye can be helpful in the development of more eco-friendly and cost-effective solar cells with commercially promising DSSC. [ABSTRACT FROM AUTHOR]

The subject of this study is the use of Indigo Carmine (IC) material in Schottky diode application. The p-Si crystal was chosen as the base material for diode fabrication. One surface of the p-Si metal was coated with Al metal by thermal evaporation method. Indigo carmine interface material was coated on the other surface of p-Si by spin coating method. Finally, Cr metal was coated on this material with DC sputtering method. So we obtained refence Cr/p-Si/Al diode and Cr/IC/p-Si/Al heterojunctions diode. When the current-voltage (I-V) measurements of these diodes at room temperature were examined, it was determined that the Indigo Carmine material improved the diode parameters. It was determined from the I-V measurements of the Cr/IC/p-Si/Al diode for different temperatures that the ideality factor (n) decreased and the barrier height (Φb) value increased with the increasing temperature. These changes with temperature have been attributed to the inhomogeneous distribution in the potential barrier. In addition, the change of diode parameters with temperature showed that the diode has a double Gaussian distribution. [ABSTRACT FROM AUTHOR]

Dynamic charge carrier transport behavior in the zirconium (Zr) oxide was investigated based on the frequency-dependent capacitance-voltage (C-V) and temperature-dependent current-voltage (I-V) measurements. The Zr oxide was formed on the ZIRLO and newly developed zirconium-based alloy (NDZ) by corrosion in the PWR-simulated loop at 360°C. The corrosion test for 90 days showed that the NDZ exhibits better corrosion resistance than ZIRLO alloy. Based on the C-V measurement, dielectric constant values for the Zr oxide was estimated to be 11.28 and 11.52 for the ZIRLO and NDZ. The capacitance difference between low and high frequency was larger in the ZIRLO than in the NDZ, which was attributed to more mobile electrical charge carriers in the oxide layer on the ZIRLO alloy. The current through the oxide layers on the ZIRLO increased more drastically with increasing temperature than on the NDZ, which indicating that more charge trap sites exist in the ZIRLO than in NDZ. Based on the dynamic charge carrier transport behavior, it was concluded that the electrical charge carrier transport within the oxide layers was closely related with the corrosion behavior of the Zr alloys.

Some issues of improving the technology of obtaining thin-film (d ≈ 1.0 μm) elements with anomalous photovoltaic properties from cadmium chalcogenides by thermal evaporation in vacuum in separate portions on transparent dielectric substrates are considered. The experimental results of studying the current-voltage, lux-ampere, lux-voltage and deformation characteristics of CdTe, CdSe, CdS polycrystalline films are analyzed. It is shown that the obtained samples have linear I - V, L - A, temperature (T ≈ 120-320 K) and deformation characteristics (ε ≈ -3 · 10-5, 3 · 10 -3 arb. units). Therefore, they can serve as promising photocells for the producing of film photodetectors sensitive to mechanical deformation in the visible and near-IR regions of the radiation spectrum. [ABSTRACT FROM AUTHOR]

This paper presents an electrical analysis of various diameters of two p-types of GaAs/Al0.9Ga0.1As and two p-types of GaAs/Al0.3Ga0.7As/Al0.9Ga0.1As distributed Bragg reflectors (DBRs) mirrors structure grown on undoped and on p-doped GaAs, which affects the characteristics of 1300 nm vertical cavity surface emitting lasers (VCSELs) and vertical cavity semiconductor optical amplifiers (VCSOAs). Electrical characterizations and Hall measurements of current−voltage (IV) for GaAs/Al0.9Ga0.1As linear DBRs and GaAs/Al0.3Ga0.7As/Al0.9Ga0.1 As graded DBRs were also performed at temperatures between 13 and 300 K. Consequently, p-type DBRs are designed with graded composition interfaces technique. The smaller mesa diameters are used to reduce vertical and longitudinal resistances and to limit the heating effect and improve the characteristics of VCSEL/VCSOA devices.

The present study aims at estimating the values of an electrochemical model parameter of a proton exchange membrane fuel cell (PEMFC). A variant of the particle swarm optimization (PSO) algorithm is adopted. This variant introduces a constriction coefficient to better regulate the convergence of the numerical code. Parameters' identification of the PEMFC stack model is performed by specifying a range for each. Validity of the adopted approach is confirmed by confronting simulation results with experimental data in terms of current–voltage polarization curves. It should be noted that the optimal value of the objective function is largely affected by the lower and upper values of the parameters. Comparison of present results with other optimization methods shows a noticeable improvement in PEMFC stack performance when using particle swarm optimization algorithm with constriction coefficient (PSO-χ). This confirms that this version of PSO algorithm is very suitable for the optimization and parameter estimation of PEMFC stack modeling. [ABSTRACT FROM AUTHOR]

This paper presents an electrical analysis of various diameters of two p-types of GaAs/Al0.9Ga0.1As and two p-types of GaAs/Al0.3Ga0.7As/Al0.9Ga0.1As distributed Bragg reflectors (DBRs) mirrors structure grown on undoped and on p-doped GaAs, which affects the characteristics of 1300 nm vertical cavity surface emitting lasers (VCSELs) and vertical cavity semiconductor optical amplifiers (VCSOAs). Electrical characterizations and Hall measurements of current-voltage (IV) for GaAs/Al0.9Ga0.1As linear DBRs and GaAs/Al0.3Ga0.7As/Al0.9Ga0.1As graded DBRs were also performed at temperatures between 13 and 300 K. Consequently, p-type DBRs are designed with graded composition interfaces technique. The smaller mesa diameters are used to reduce vertical and longitudinal resistances and to limit the heating effect and improve the characteristics of VCSEL/VCSOA devices. [ABSTRACT FROM AUTHOR]

We present the combined analysis of electroluminescence (EL) and current–voltage (I–V) behavior of single, freestanding (In,Ga)N/GaN nanowire (NW) light-emitting diodes (LEDs) in an unprocessed, self-assembled ensemble grown by molecular beam epitaxy. The data were acquired in a scanning electron microscope equipped with a micromanipulator and a luminescence detection system. Single NW spectra consist of emission lines originating from different quantum wells, and the width of the spectra increases with decreasing peak emission energy. The corresponding I–V characteristics are described well by a modified Shockley equation. The key advantage of this measurement approach is the possibility to correlate the EL intensity of a single-NW LED with the actual current density in this NW. This way, the external quantum efficiency (EQE) can be investigated as a function of the current in a single-NW LED. The comparison of the EQE characteristic of single NWs and the ensemble device allows for a quite accurate determination of the actual number of emitting NWs in the working ensemble LED and the respective current densities in its individual NWs. This information is decisive for a meaningful and comprehensive characterization of a NW ensemble device, rendering the measurement approach employed here a very powerful analysis tool.

The current-voltage characteristic of an injection photodiode of the In–n-CdS– p-Si–In structure, which can operate in a wide spectral range of electromagnetic radiation at room temperature, has been investigated. It is found that the current-voltage characteristic of such structures has a power-law dependence of the current on the voltage. It is shown that in the area of the sharp increase in current of the current-voltage characteristics, participation of defect-impurity complexes in recombination processes becomes decisive.

Despite the large number of studies on CdO, it was until very recently the system properties Ga-doped CdO/PS was not recognize well. In this paper, photodetector of Gadoped CdO/Si and Ga-doped CdO/PS nanocrystalline with different Ga ratios (0, 3, and 7%) have been prepare by spray pyrolysis deposition (SPD). The structural properties of un doped CdO and doped films were characterized by X-ray diffraction, which refer to that the CdO thin films have cubic structure. The energy gap of un doped film and doped with Ga increased from 2.5 to 3.56 eV with increasing Ga ratios. I-V characteristics of Gadoped CdO/PS photodiodes without illumination exhibit good rectification behavior compared with Si substrate, and the value of photocurrent increased with Ga ratios increased. The spectral responsivity curves (A/W) of all devices prepared allow acceptable sensitivity response in the visible wavelength region, and shifted toward ultra-violet region with increase Ga ratios. [ABSTRACT FROM AUTHOR]