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An investigation was conducted on the characteristics of current and voltage in a heterostructure setup comprising a CdS/Silicon Schottky barrier diode. The investigation encompassed a broad spectrum of temperature conditions, spanning from 200 to 400 K. Based on the simulation results, the saturation current, ideality factor, series resistance measurement, and Schottky barrier height demonstrated favorable outcomes. Based on this premise, empirical evidence demonstrates that an increase in temperatures leads to a decrease in the ideality factor, accompanied by an increase in the barrier height. The temperature alterations within the implemented heterostructure lead to a Schottky barrier height ranging from 1.2 to 1.5 eV. At temperatures below 300 K, the height of the barrier exhibited slight irregularity, which became more pronounced with increasing temperature. Furthermore, an analysis was conducted on the C–V and G–V characteristics of the CdS/Si heterostructure. Various analyses of C–V and G–V have been conducted in order to gain a comprehensive understanding of the structure. A C–V analysis was conducted for frequencies of 1 kHz and 1 MHz, while also considering temperature variations. The G–V experiment encompassed a frequency range of 1 KHz to 1 MHz, as well as variations in temperature. Throughout the investigation, various factors such as effective barrier height and built-in voltage were identified. Based on the results obtained from the investigation, it has been determined that the effective barrier height at room temperature is 0.98 eV. [ABSTRACT FROM AUTHOR]

Aluminum-doped lanthanum phosphate (LaPO4:Al) nanoparticles were synthesized using a simple co-precipitation technique. The x-ray diffraction patterns show that all of the collected samples have a monoclinic structure with crystallite size (D) increasing from 13 to 17 nm as the Al-doping concentration increases, whereas the band gap values dropped from 5.46 eV to 3.93 eV with the increased Al-doping concentration. The effect of I–V electrical performance was methodically investigated in 10% Al-doped LaPO4-based metal–insulator–semiconductor (MIS)-type Schottky barrier diodes (SBDs). The experimental results reveal that the changes in the barrier height of 0.772 eV and the lowest ideality factor of 2.95 were both attained under light irradiation. In the comparison of the values of the undoped Cu/LaPO4/n-Si and Cu/Al-LaPO4/n-Si Schottky barrier diodes, the Al-LaPO4/n-Si Schottky barrier diode was found to possess a significantly better barrier height (ϕB) and ideality factor values (n) than the other. The reported results in this work are among the best to date for 10% Al-doped LaPO4 Schottky barrier diodes. Synthesis of undoped and Al doped LaPO4 NPs and fabrication of Cu/AL-LaPO4/n-Si based metal-insulator-semiconductor (MIS) Schottky barrier diodes (SBDs). [ABSTRACT FROM AUTHOR]

Plasmonic photovoltaics integrate nanoparticles into the active layer to enhance power absorption. However a gap exists between simulated and experimental IV characteristics. Fabrication studies have attributed the issues to fabrication resolution, and recombination with no detailed step-by-step characterization. To address this issue, the paper presents a comprehensive optical and electrical study of a new plasmonic crescent nanoparticle (CNP). These particles serve as a near-field confinement source to enhance the efficiency of perovskite TiO 2 -MAPbI 3 -Spiro solar cells. The proposed design demonstrates that an optimized structure with polarization-dependent multiple modes can offer broad-spectrum absorption across both the visible and near-infrared spectra, resulting in a 15% improvement in the total absorption. The notably high stability of absorption with respect to parameter variation is a remarkable key factor. Employing Charge Transport (CHARGE) solver, the electrical characterization of the proposed plasmonic device is performed in a step-by-step procedure using three different models to characterize the sources of efficiency degradation The ohmic contact reduces quantum efficiency by 11%. Moreover, when surface recombination is considered, the degradation increases significantly to 54%, which matches the experimental studies in the literature. The paper also suggests incorporating a passivation layer which demonstrates its impact in enhancing the quantum efficiency from 18.2% to 22.2%. • Design of silver nanoparticles with multiple polarization dependent modes to provide wide band absorption spectrum. • Addressing the gap between the simulation and experimental studies of plasmonic solar cells in literature. • Charcterization of silver and recombination effect of nanoparticles in plasmnic solar cells. • Reporting enhancement in the quantum efficiency in terms of increased output power from 18.2% to 22.2% using the proposed passivation. [ABSTRACT FROM AUTHOR]

There is currently an energy crisis that has led to photovoltaic operators maximizing their resources, making soiling a problem to consider in order to ensure project profitability. Energy production costs are strongly affected by the use of scarcely efficient cleaning techniques that are not suitable for a particular type of contaminant, climate, and installation. This paper introduces a technology that is suitable for studying soiling, thus decreasing the number of variables studied and reliable results were obtained. Our attention is focused on deposited material physicochemistry, local geology, and installation effects. Analysis via scanning electron microscopy and pits revealed a similarity between local geological processes and module soiling, with gypsum being responsible for soil and module cementation. Analysis with Atomic Force Microscopy confirms the cementation effect and crust formation on the lower part of the photovoltaic glass, the latter concentrating in the greatest amount of cemented material. Using a solar simulator, the characteristic curves produced by the cemented material were studied, and it was determined that the lower part of the glass produced the greatest losses (27%). Thus, a non-uniformity deposition was generated, creating resistance between the cells. From the data obtained, it was possible to make recommendations regarding making decisions about plant cleaning, instead of only considering the physicochemical analysis of the deposited material. [ABSTRACT FROM AUTHOR]

• EVA films of 18, 24 and 33% VA content by weight are prepared to fabricate mini-modules, which are subjected to DH ageing for 1000 h at 85 °C & 85% RH. • The P max , G c and resistivity reduce and ΔYI increases for the modules containing EVA33 after ageing but remains unaltered for EVA24 and EVA18. • It has been found that the films of EVA18 and EVA24 are resilient compared to EVA33. The photovoltaic (PV) module manufacturers use ethylene vinyl acetate that contains 28 to 33% by weight vinyl acetate (VA) for the encapsulation application. However, it has been found in various field surveys that EVA degrades during its operation in the field. The resilience of ethylene vinyl acetate against environmental stressors can be enhanced by optimising its vinyl acetate (VA) content as has been seen in the few studies done on free-standing EVA films. However, no such comparative study has been carried out on EVA films placed in a module mimicking the actual structure of a PV module. Therefore, in this work EVA films containing 18, 24 and 33% VA content by weight are prepared with the necessary additives to fabricate mini-modules. These mini-modules have been subjected to damp-heat (DH) ageing for 1000 h at 85 °C temperature and 85% relative humidity (RH) according to IEC 61,215 standard. The power output, adhesion strength and volume resistivity reduce and YI increases for the modules containing EVA33 after ageing. However, no significant changes are observed for the above-mentioned properties for the modules containing EVA24 and EVA18. This study presents findings of 1000 h of DH ageing as per IEC standards for mini-modules containing different EVA films and observed that the films of EVA18 and EVA24 are resilient compared to EVA33. Moreover, the findings on mini-modules have a few differences with prior studies done on free-standing EVA the films. [ABSTRACT FROM AUTHOR]

The presented paper describes the study of ligand-exchange dependent properties of mercury chalcogenides (HgS, HgTe) colloidal quantum-dot thin films. Thin films of colloidal quantum dots of mercury telluride and mercury sulfide were prepared using a layer-by-layer deposition technique applying dip-coating and spin-coating methods. The impact of the synthetic procedure of quantum dots, solvent and concentration of colloidal solution on the thin films’ properties was analyzed. By using concentrated colloidal solutions in tetrachloroethylene, we succeeded in the preparation of homogeneous thin films with minimal roughness. The surface morphology and thickness of the thin films were determined using AFM. The voltage–current characteristics of photosensitive devices applying various ligand exchanges were investigated.

There is currently an energy crisis that has led to photovoltaic operators maximizing their resources, making soiling a problem to consider in order to ensure project profitability. Energy production costs are strongly affected by the use of scarcely efficient cleaning techniques that are not suitable for a particular type of contaminant, climate, and installation. This paper introduces a technology that is suitable for studying soiling, thus decreasing the number of variables studied and reliable results were obtained. Our attention is focused on deposited material physicochemistry, local geology, and installation effects. Analysis via scanning electron microscopy and pits revealed a similarity between local geological processes and module soiling, with gypsum being responsible for soil and module cementation. Analysis with Atomic Force Microscopy confirms the cementation effect and crust formation on the lower part of the photovoltaic glass, the latter concentrating in the greatest amount of cemented material. Using a solar simulator, the characteristic curves produced by the cemented material were studied, and it was determined that the lower part of the glass produced the greatest losses (27%). Thus, a non-uniformity deposition was generated, creating resistance between the cells. From the data obtained, it was possible to make recommendations regarding making decisions about plant cleaning, instead of only considering the physicochemical analysis of the deposited material.

The electrical characteristics of photovoltaic (PV) modules are affected by solar radiation and module temperature in outdoor environment. It was found that polycrystalline gained a yearly 0.50°C more average module temperature than monocrystalline. Non-crystalline amorphous modules got a yearly 0.83°C more average temperature than thin film modules. The attainment and release of module temperature was related with material properties of PV module technologies. The amorphous module gave 5.7%, 2.7% and 15.0% more yearly average open-circuit voltage than polycrystalline, monocrystalline and thin film modules. Besides that, the thin film modules gave 6.5% and 1.7%, 9.3% and 4.0%, and 11.3% and 8.8% more yearly average normalized short-circuit current and power output than polycrystalline, monocrystalline and thin film modules respectively. It was shown that the maximum annual average open-circuit voltage was given by amorphous modules and maximum short-circuit current and power output by thin film modules during the study period. [ABSTRACT FROM AUTHOR]

Recently, photovoltaic energy is growing up rapidly especially in solar cell fabrication. Perovskitebased solar cell technology has been focus of interest from photovoltaic technologies due to its high power conversion efficiency and low processing cost comparing by others. The first step in solar cell fabrication is the simulation, which gives an idea about effect of different parameters on power conversion efficiently with less efforts and costs. There are a lot of software that are used in solar cell simulations, such as GPVDM, SCAPS and Silvaco Atlas. Therefore, several structures are used in perovskite-based solar cells, such as n-i-p, p-i-n, n-p-p and p-p-n. Our study is focused on n-i-p structure. For the present paper we used Silvaco Atlas software because it contains a lot of physical and recombination models based on solving the Poisson partial differential equation and carrier continuity. Moreover, this paper shows numerical simulations of planar heterojunction solar cell structures that have the following layers: hole transporting layer (HTL) / perovskite absorber layer (PVK) / electron transporting layer (ETL). However, different layer materials of ETL are used, namely cadmium sulfide (CdS) and zink oxide (ZnO) in order to study the behavior of solar cells based on perovskite (CH3NH3PbI3). This latter material used in this paper's simulation belongs to organic/inorganic type. The obtained results show that the solar cell structure based on CdS exhibits a better performance in term of power conversion efficiency (PCE) compared to that based on ZnO when using the same layer thickness. [ABSTRACT FROM AUTHOR]

Solar photovoltaic technology is a major form of renewable energy and is gaining worldwide interest due to rising energy demands and concerns of environmental effects. Kuwait is located on latitude of 29.22 o N and enjoys high solar radiation in most parts of the year (7.65 kWh/m2.day). However, Kuwait suffers from dust and sand storms due to its very little vegetation, dryness, weightless-textured surface soil and frequent unstable strong air currents. This work investigates the performance of solar PV panel based on HIT silicon cells under Kuwait environment and assesses the effect of cooling in reducing the impact of dust on the PV power output. Measurements showed that dust reduces the power output by 16% at midday. This effect can be partially compensated through cooling the PV panel. [ABSTRACT FROM AUTHOR]

Abstract: The electronic properties of multicrystalline solar silicon materials are dominated by low-lifetime defect regions containing recombination-active grain boundaries and dislocations. Besides reducing the carrier collection probability, these regions increase the dark saturation current density J 01, which governs the open circuit voltage. By applying lock-in thermography with spatial deconvolution it is shown that the dominant contribution to J 01 comes from recombination-active grain boundaries and to a lower degree from intra-grain defects like dislocations. [Copyright &y& Elsevier]

Abstract: A p–n heterostructure diode of polyaniline (PANI) and ZnO nanoparticles was prepared by the electrophoretic deposition of PANI on ZnO nanoparticles thin film coated fluorine doped tin oxide (FTO) glass at room temperature. The morphological, structural and optical studies substantiated the penetration, bonding and the interaction of PANI molecules with ZnO nanoparticles thin film substrates. The prominent blue shift in UV-Vis spectra indicated the strong interaction between ZnO and PANI through the decreased degree of orbital overlap between electrons of the phenyl rings with the lone pair of the nitrogen atom in the PANI molecules. The characteristics of PANI/ZnO heterostructure diode showed weak rectifying behavior with non-linear nature of curve of PANI/ZnO heterostructure device. The typical ohmic behavior was observed by the characterization of PANI/ZnO heterostructure at the interface of PANI and ZnO thin film layer without top Pt thin layer contact. [Copyright &y& Elsevier]

Employing the monotonicity approach and the theory of orientation preserving circle homeomorphisms, we provide a rigorous analysis on the IV characteristics of the coupled Josephson junctions including an interference term in a specified parameters region. In particular, when the system is driven by a dc-current, we show that there exist either globally stable single-wave-form solutions if and only if the average voltage is nonzero, or equilibria if and only if the average voltage vanishes. [ABSTRACT FROM AUTHOR]

In this work we report on experiments about the dynamical resonance properties of annular Josephson junctions of intermediate (with respect to the Josephson penetration depth) size. We investigate the dynamical states of the first four resonances appearing in the current–voltage characteristic. The experiment conditions permit a simultaneous observation of zero field steps (ZFSs) and Fiske steps (FSs) and interplay between them. Two sets of measurements were performed: in the absence of trapped flux, with trapped flux. The magnetic field induces either a sharp or a continuous transition from the ZFSs to FSs. We interpret this observed behaviours in terms of dynamical states involving fluxon–antifluxon pairs or states involving fluxons of the same polarity. We show that is possible to fit always the FS behaviour beyond a magnetic field threshold by using a theory strictly valid for small annular junctions and that the same theory can also reproduce, in some specific case, the ZFS behaviour. [Copyright &y& Elsevier]