Photoelectric Parameters Research Articles

Investigation of GaAs-Based Laser Diode Adopting an Al Composition Gradient Double Waveguide Structure and its Photoelectric Properties

The double waveguide structure of a 1060 nm laser diode with different Al composition linear gradient was designed for achieving high output power. In contrast to the single waveguide layer with Al-free composition gradient structure, the double waveguide layer with a reverse Al composition gradient from n side to p side showed excellent optoelectronic properties. We found that the reverse Al composition gradient double waveguide layer could decrease injection potential barrier for electrons and holes, as well as has a high block leakage potential barrier, which can be help to increase carrier transport and optical confined factor. Meanwhile, it can improve sheet carrier concentration in order to decrease non-radiative recombination. When the injection current is 6 A, the maximal output power and peak wall-plug conversion efficiency are 6.12 W and 81.1%, respectively. The influencing mechanism of these photoelectric parameters on power and wall-plug conversion efficiency was discussed. The novel waveguide structure will be favorable for designing epitaxial structure and providing a theoretical basis for high-power laser diode.

Performance enhancement of Sb2(S,Se)3 solar cells through neodymium ion flow doping

Doping the light absorber layer of antimony chalcogenides with extrinsic ions is an effective approach for improving their photovoltaic quality. These dopant ions generally reside at positions other than the crystal lattice or form an alloy (e.g., AgSb(S,Se)3) with a poor device performance. Therefore, incorporating such ions into an antimony chalcogenide lattice such that there is a positive influence on device quality would be highly useful. Herein, doping of Nd3+ for Sb2(S,Se)3 is carried out via a modified hydrothermal deposition process. Notably, these ions are incorporated into the crystal lattice and migrate to the CdS/Sb2(S,Se)3 interface after doping, which are characterized using X-ray diffraction, X-ray photoelectron spectroscopy, and time-of-flight secondary ion mass spectrometry. Nd3+ doping produces benign effects on the crystal orientation, film morphology, optoelectronic properties, and defect passivation of the Sb2(S,Se)3 films. Consequently, all the photoelectrical parameters of Sb2(S,Se)3 solar cells doped with Nd3+ are enhanced, delivering a remarkable efficiency of 8.24 %. Furthermore, the best device stored in air only shows a slight decrease in efficiency in the 2400-h aging test. Overall, this study provides an effective doping strategy to improve the photovoltaic quality of Sb2(S,Se)3 films.

SILICON PHOTODIODE FOR TELECOMMUNICATIONS (FSO) WITH INCREASED SPEED AND SENSITIVITY AT 980 nm

One of the basic elements of Free Space Optics is a photodiode, which must have a high level of sensitivity to radiation in the range of 0.8-1 μm, and be fast-acting. In our case, the chosen wavelength is 980 nm, which corresponds to the wavelength of a vertical-cavity surface-emitting laser (VCSEL). The optimization of the photodiode design is carried out taking into account the uniform generation of the photocurrent with a uniform volume charge density inside the crystal when receiving radiation with a working wavelength. The current of the photo signal in the external circuit, in this case, depends on the modulation frequency, the width of the space charge region (SCR), the mobility of minor charge carriers and the amount of bias at the p-n junction. This allows you to significantly manipulate the rise time of the transient characteristic of the photodiode, and the use of double passage of the radiation beam throughout the SCR, you can obtain a significant increase in sensitivity. The subject is the construction of a photodiode, which at a wavelength of 980 nm has small values of the rise time and high values of current monochromatic sensitivity. The goal is to substantiate and create a design of a photodiode with increased current monochromatic sensitivity and reduced rise time at 980 nm wavelengths for operation in FSO. Task: To analyze the factors affecting the sensitivity and rise time of the photodiode when working at a wavelength of 980 nm, as well as to develop the design of the photodiode and investigate it. Methods: mathematical analysis of photoelectric parameters of a photodiode taking into account the mechanism of generation of minor charge carriers. Modeling of the photodiode design. A planar technology for silicon was used to manufacture the photodiode. The technical solution is based on the optimization of the modulation frequency, the width of the SCR, the mobility of minor charge carriers and the amount of displacement at the p-n junction, as well as ensuring the double passage of radiation through the photodiode crystal. The result was also achieved by etching the mesastructure from the reverse side of the photodiode, the area of which is the projection of the photosensitive element of the photodiode, and the width of the silicon plate above the mesastructure should be about 50 μm. Results: Factors affecting the current monochromatic sensitivity of the photodiode and its rise time were determined and taken into account. A new photodiode design with increased sensitivity and reduced rise time has been created. Comparative studies of the manufactured batch of created photodiodes and FD-255A photodiodes were conducted, which showed that the proposed photodiode really has a current monochromatic sensitivity at a wavelength of 980 nm of at least 0.55 A/W. At the same time, its rise time was reduced from 50 ns to 20 ns. compared to the serial photodiode FD-255A.

Optimization of silicon solar cell design for use under concentrated solar irradiation

The task of reducing the cost of a unit of photoelectric-generated electricity is still relevant today. One of the most effective ways to do that is to use concentrator photovoltaic energy conversion systems with cheaper, small-area silicon solar cells (SC), because they require significantly less semiconductor material to make. In this study, the authors develop solutions to optimize the design and improve the manufacturing technology of silicon SCs of the combined diffusion-field type. Such SCs are used to concentrate solar irradiation. The authors propose design and technological solutions for the development and manufacture of a concentrator unit based on the Fresnel lens, which is designed to measure the photoelectric characteristics of SCs when concentrating solar irradiation. Next, the photoelectric characteristics of the combined diffusion-field type SCs were investigated under concentrated solar irradiation in natural sun conditions. The degree of concentration varied from 1X to 100X. Measuring the light I –V characteristics allowed determining photoelectric parameters of the cells — shortcircuit current, open-circuit voltage, fill factor and photoconversion efficiency. The obtained experimental results are in good agreement with the results of theoretical modeling. It is shown that due to the minimization of the specific series resistance, the samples of such SCs have high values of operational parameters in the range of natural solar irradiation concentration K=1X–100X.

Low-Cost Solar Energy Harvesting: A Study on Dye-Sensitized Solar Cells Using Inthanin Leaf Extract as a Natural Photosensitizer


 
 
 
 The world is actively pursuing renewable energy resources to combat environmental pollution and greenhouse gas emissions caused by the burning of fossil fuels. Solar energy is the most abundant, continuously available form of renewable energy, and dye-sensitized solar cells (DSSCs) are being explored as an alternative to traditional silicon-based solar cells due to their low cost of materials, ease of production, and efficiency. The photoanode is a crucial component in DSSCs, and the main challenges faced by these solar cells are charge recombination and low light harvesting ability. This study aims to investigate the efficacy of natural dyes as the sensitizer for the fabrication of DSSCs. Natural pigments were extracted from Inthanin leaves using the solvent extraction technique. The concentration and composition of the pigment were analyzed through pigment analysis utilizing UV a spectrophotometer. Inthanin has a higher chlorophyll a to b ratio. A higher chlorophyll a to b ratio has been shown to be associated with improved light harvesting and electron transport efficiency. This is because chlorophyll a is more efficient at transferring electrons to the electron transport chain than chlorophyll b. The higher chlorophyll a to b ratio could lead to improved electron transfer to the photoanode. The photoelectric parameters of the DSSC were evaluated using I-V characterization. DSSCs coated with Inthanin dye extract produced a short circuit current density (Jsc) of 0.02 mA/cm2, open circuit voltage (Voc) of 0.07 V, fill factor (FF) of 33% and an efficiency (????) of 0.1%.
 
 
 

A study on investigation of electrical properties of Au/Chlorophyll-a/n-Si/Al structure

The chlorophyll-a (Chl-a) thin film has been formed on the n-Si substrate using a spin-coater. The electrical properties of the Au/Chl-a/n-Si/Al structure have been examined with the data obtained from the current–voltage (I–V) measurements in the dark and under illumination at room temperature. The ideality factor (n) and barrier height (Φb) values have been calculated as 1.24 and 0.799 eV in the dark and 1.08 and 0.824 eV in daylight at room temperature. Also, I–V measurements were taken under different illuminations, and some photoelectrical parameters of the Au/Chl-a/n-Si/Al structure, such as photocurrent, photosensitivity, and Ion/Ioff, were investigated. The results show that the Chl-a thin film can be utilized to fabricate photodiodes and solar cells.

Perovskite based low-powered hybrid UV photodetector with RF sputtered metal oxide carrier transport layers

The authors here have reported two low-powered UV photodetectors designed with and without NiO as a hole transport layer (HTL) having the hybrid heterostructure of ZnO/CH3NH3PbI3 (Device1) and ZnO/CH3NH3PbI3/NiO (Device2) respectively. Both the devices showed good photoelectric parameters in UV region under self-powered condition. However, in Device1 due to its high dark current (390 nA), the responsivity (Rλ) and specific detectivity (D*) were degraded which were improved in Device2 (low dark current of 1.7 nA) after incorporating the NiO as an HTL. The maximum D* values of Device1 and Device2 in UV region are found to be of 5.5 × 108 Jones and 7.8 × 109 Jones at 0 V respectively. Moreover, an ultra-fast device response was obtained for Device2 with rise and fall times of 50 ms and 40 ms respectively. Also, the accumulation capacitance and conductance were found to be higher for Device2 making it a good candidate for low power photodetection application.

P‐3.1: Research on Display Brightness Perception and Visual Comfort Representation Model

People's perception of brightness and visual comfort in different light environments are important indicators of display products. The perception of the brightness of the human eye is often different from the actual brightness of the display. This is because there is a difference between the perceived brightness and the physical brightness. The luminous body of the same physical brightness may give people different feelings, thus producing different perceived brightness. In the complex optical environment, the existing photoelectric measurement parameters may not be able to accurately describe the perception effect of the display device. The research on perceived brightness and visual comfort has a long history, but in view of the increasingly complex light environment and the development of diversified display equipment, the perceptual brightness model needs to be further modified and improved. Based on the modeling research of perceived brightness, this paper studies the perception mechanism of human eyes, analyzes the shortcomings of the current mainstream or new display devices, and proposes a more comfortable display technology based on people's viewing habits, ambient light and display content.

In Ukrainian

During the preparation of silicon substrates for the manufacture of silicon p-i-n photodiodes, the effect of the presence of chemical-dynamic polishing and the depth of etching on the electrical parameters of the FD was observed. The quality of the polishing operation also affected the optical and photoelectric parameters of the samples. These effects required detailed study. The article investigates defect formation during the operation of chemical-dynamic polishing in the technology of silicon p-i-n FDs and determines the optimal modes of polishing the front and back sides of the substrates. The composition of the etching mixture was HNO3:HF:CH3COOH = 9:2:4. CDP has a significant effect on dark currents. This operation should be performed before heat treatments and before diffusion in the reverse direction to obtain minimum values of the dark current. The optimal polishing depth of the front side of the substrate is 20–25 microns (if we take into account the etching of the reverse side – 35–40 microns in total), the reverse side before boron diffusion – 10–15 microns. The main factors that affect the appearance of defects during polishing have been elucidated. Thus, when the concentration of the components of the polisher medicine for the СDP changes significantly, its properties change significantly – the polisher can become selective, since its composition is similar to the selective polisher of Dash. In order to avoid this, it is necessary to carry out incoming control of component acids. If there are inclusions of another phase in the volume of ingots and, accordingly, on the surface of the substrates, clusters of point microdefects of different sizes, or defects acquired in the process of mechanical processing, there is unevenness of etching and violation of planar parallelism. At a high speed of rotation of the tank with the polisher, the depleted layer of the solution may not have time to form near the surface of the substrates or be “broken off” from the surface by the flow of liquid, which leads to selective etching of the plates. This effect can be manifested in the so-called texturing of substrates, which increases the level of dark current and reduces sensitivity. In the case of the reverse side of the СDP, before boron diffusion, the front side is protected with a chemically resistant varnish. If the thickness of the varnish is insufficient, the formation of punctures in the protective layer is possible. In this case, during the polishing operation, the herbaceous material flows under the varnish layer and the brightening or masking oxide is etched. To prevent the described phenomena, we recommend applying two layers of varnish with intermediate drying. Before the end of the polishing process, it is inadmissible to remove the plates from the container with the herbal agent, because drops of the herbal agent remain on the surface of the substrates. In places where there are drops, a violent reaction begins with the release of nitric acid vapors and strong heating. As a result of this reaction, the plates are strongly etched and spots, depressions-craters and black coating of silicon oxide are formed on their surface. In the event of the appearance of the described damaged surface and the unsuitability of the substrates for further technological operations, it is necessary to remove the surface layers by mechanical methods and again to perform the СDP.

Slot-Die-Coated Active Layer for Printed Flexible Back-Contact Perovskite Solar Cells

Perovskites have already shown potential as active layers in photovoltaic applications. Furthermore, a low-cost and simple solution processing technology allows perovskites to be used in flexible and printed electronics. Perovskite solar cells (PSC) with a back-contact (BC) structure, in which the electrode system is based on a quasi-interdigitated back-contact (QIBC) design, promise to increase the power conversion efficiency (PCE) of devices beyond those that can be obtained using PSCs with a traditional sandwich structure. While the spin-coating technique is used to deposit the perovskite layer of lab-scale BC PSCs, the application of large-area printing techniques to deposit the perovskite layer of such devices is yet to be explored. Therefore, this work demonstrates an application of the slot-die coating technique to print the perovskite active layer of BC PSCs with QIBC electrodes on flexible polymer substrates. The morphology of the obtained perovskite films on QIBC electrodes are investigated and the primary photoelectric parameters of the resulting BC PSCs are measured. The charge carrier recombination processes in the fabricated BC PSCs are investigated and the dominant mechanism for carrier loss in the devices is determined. The findings of the work give an insight into the properties of the slot-die-coated perovskite active layer of BC PSCs and points to exciting new research opportunities in this direction.

Effect of detector photoelectric parameters on ptychographic iterative engine

An analytical solution model for ptychographic iterative engine (PIE) is proposed. In this model, PIE can be described as a system of linear equations between the sample and the illumination in the frequency domain. This system of linear equations (<i> <b>AX</b> </i> = <i> <b>B</b> </i>) is derived with the spectrum of the illumination as the coefficient (<i> <b>A</b> </i>), the spectrum of the sample as the unknown (<i> <b>X</b> </i>), and the intensity of the diffraction pattern as the vector (<i> <b>B</b> </i>). Hence, the sample can be recovered by solving this linear system. In PIE, the detector (such as Pike F-100, AVT) has a large resolution, meaning that 1000 × 1000 linear equations can be generated by recording a single pattern. It is still the case, however, that the number of obtained equations is smaller than the number of unknowns, leading to the inability to obtain a unique solution about the sample. Relative motions of sample and illumination, can generate more diffraction patterns to construct a sufficient number of linear independent equations. For coefficient (<i> <b>A</b> </i>), since the initial illumination is known, the illumination after shifting can still be obtained by recording its shifting distance. Hence the unique solution for the sample can be directly obtained by solving this linear independent system of equations. Simultaneously, the photoelectric parameters of the detector have a significant influence on the imaging quality of PIE. Using this linear system, the photoelectric parameters of the detector can be characterized by the number of linear equations and unknowns in each equation. According to the conditions that there is a unique solution in the system of equations and the requirements of the photoelectric parameters (such as pixel sampling interval, width of target surface, pixel size, sensitivity and dynamic range), the influence of the reconstruction for PIE is quantified theoretically. Obviously, the numerical simulation results based on this theory not only verify the correctness of the theoretical analysis and predictions, but also reveal the physical mechanism of recovering high-quality results in imperfect photoelectric parameters of detector, which can contribute to improving the quality of their reconstruction and optimizing the experimental setup.

Non-steady-state photo-EMF in a periodically poled MgO : LiNbO-=SUB=-3-=/SUB=- crystal

The diffusion mode of the non-steady-state photo-EMF excitation is investigated in periodically poled MgO : LiNbO3 crystal at light wavelength λ=457 nm. The signal excitation is carried out along the polar axis of the crystal; the dependencies of the signal amplitude versus the phase modulation frequency, intensity and spatial frequency of the interference pattern are studied in this geometry. The analysis of these dependencies allows determining the photoelectric parameters of the material --- the type, value and relaxation time of the photoconductivity, as well as the diffusion length of charge carriers. Keywords: non-steady-state photo-EMF, periodic domain struc ture, lithium niobate.

Analyzing the ZnO and CH3NH3PbI3 as Emitter Layer for Silicon Based Heterojunction Solar Cells

Today, it has become an important task to modify existing traditional silicon-based solar cell factory to produce high-efficiency silicon-based heterojunction solar cells, at a lower cost. Therefore, the aim of this paper is to analyze CH3NH3PbI3 and ZnO materials as an emitter layer for p-type silicon wafer-based heterojunction solar cells. CH3NH3PbI3 and ZnO can be synthesized using the cheap Sol-Gel method and can form n-type semiconductor. We propose to combine these two materials since CH3NH3PbI3 is a great light absorber and ZnO has an optimal complex refractive index which can be used as antireflection material. The photoelectric parameters of n-CH3NH3PbI3/p-Si, n-ZnO/p-Si, and n-Si/p-Si solar cells have been studied in the range of 20–200 nm of emitter layer thickness. It has been found that the short circuit current for CH3NH3PbI3/p-Si and n-ZnO/p-Si solar cells is almost the same when the emitter layer thickness is in the range of 20–100 nm. Additionally, when the emitter layer thickness is greater than 100 nm, the short circuit current of CH3NH3PbI3/p-Si exceeds that of n-ZnO/p-Si. The optimal emitter layer thickness for n-CH3NH3PbI3/p-Si and n-ZnO/p-Si was found equal to 80 nm. Using this value, the short-circuit current and the fill factor were estimated around 18.27 mA/cm2 and 0.77 for n-CH3NH3PbI3/p-Si and 18.06 mA/cm2 and 0.73 for n-ZnO/p-Si. Results show that the efficiency of n-CH3NH3PbI3/p-Si and n-ZnO/p-Si solar cells with an emitter layer thickness of 80 nm are 1.314 and 1.298 times greater than efficiency of traditional n-Si/p-Si for the same sizes. These findings will help perovskites materials to be more appealing in the PV industry and accelerate their development to become a viable alternative in the renewable energy sector.

Нестационарная фотоэдс в периодически поляризованном кристалле MgO : LiNbO-=SUB=-3-=/SUB=-

The diffusion mode of the non-steady-state photo-EMF excitation is investigated in periodically poled MgO:LiNbO₃ crystal at light wavelength λ=457 nm. The signal excitation is carried out along the polar axis of the crystal; the dependencies of the signal amplitude versus the phase modulation frequency, intensity and spatial frequency of the interference pattern are studied in this geometry. The analysis of these dependencies allows determining the photoelectric parameters of the material – the type, value and relaxation time of the photoconductivity, as well as the diffusion length of charge carriers.

Production of spin coated chromium oxide (CrO3) thin layers and application in the Al/p-Si metal semiconductor structures

A novel Al/CrO3/p-Si structure was built by help the spin coating technique. CrO3 thin layer has been characterized by the XRD, UV–vis, SEM and AFM measurements. It has been observed that the CrO3 layer has amorphous structure with optical band energy value of 3.96 eV. The surface analysis of CrO3 layer by using AFM and SEM methods has been found to be rather rough that is not observed grains of any definite shape or size. Furthermore, some electronic quantities of Al/CrO3/p-Si junction by help the thermionic charge transport mechanism have been extracted by utilizing current-voltage (I-V) and capacitance-voltage data. Moreover, it has been seen that interfacial state concentration for the Al/CrO3/p-Si contact varied in the range of 8.05 × 1012 eV−1 cm2 to 6.71 × 1011 eV−1 cm−2 in darkness, and 1.23 × 1013 eV−1 cm−2 to 3.82 × 1012 eV−1 cm−2 under the illumination condition. The photoelectric parameters of the Al/CrO3/p-Si contact under 100 mW cm−2 light illumination was studied by I-V measurement.

Synthesis and electrophysical properties of CdS/ZnTe heterojunctions

In this paper results of studying CdS/ZnTe heterostructures synthesized by the quasi-closed space sublimation method on glass substrates coated with an ITO layer are described. The electrical and photoelectric properties of the structures are studied using current–voltage and capacitance–voltage characteristics in a temperature range of 30–100 °C. Analysis of the experimental data shows that the main specific feature of CdS/ZnTe structures is the formation of a high-resistance transition layer, which affects the separation of carriers at the barrier contact. The current carrier concentration in the space charge region, which is determined from the capacitance–voltage characteristics, is 1 x 1015 cm-3; this fact suggests that one of the contacting materials—ZnTe—exhibits a high resistivity. Measurements of current–voltage characteristics in the solar cell mode give the following photoelectric parameters: open circuit voltage (UOC = 0.53 V, JSC = 27–30 A/cm2, and FF = 0.25.

Atom-to-Device Simulation of MoO3/Si Heterojunction Solar Cell

Metal oxides are commonly used in optoelectronic devices due to their transparency and excellent electrical conductivity. Based on its physical properties, each metal oxide serves as the foundation for a unique device. In this study, we opt to determine and assess the physical properties of MoO3 metal oxide. Accordingly, the optical and electronic parameters of MoO3 are evaluated using DFT (Density Functional Theory), and PBE and HSE06 functionals were mainly used in the calculation. It was found that the band structure of MoO3 calculated using PBE and HSE06 exhibited indirect semiconductor properties with the same line quality. Its band gap was 3.027 eV in HSE06 and 2.12 eV in PBE. Electrons and holes had effective masses and mobilities of 0.06673, -0.10084, 3811.11 cm2V-1s-1 and 1630.39 cm2V-1s-1, respectively. In addition, the simulation determined the dependence of the real and imaginary components of the complex refractive index and permittivity of MoO3 on the wavelength of light, and a value of 58 corresponds to the relative permittivity. MoO3 has a refractive index of between 1.5 and 3 in the visible spectrum, which can therefore be used as an anti-reflection layer for solar cells made from silicon. In addition, based on the semiconducting properties of MoO3, it was estimated that it could serve as an emitter layer for a solar cell containing silicon. In this work, we calculated the photoelectric parameters of the MoO3/Si heterojunction solar cell using Sentaurus TCAD (Technology Computing Aided Design). According to the obtained results, the efficiency of the MoO3/Si solar cell with a MoO3 layer thickness of 100 nm and a Si layer thickness of 9 nm is 8.8%, which is 1.24% greater than the efficiency of a homojunction silicon-based solar cell of the same size. The greatest short-circuit current for a MoO3/Si heterojunction solar cell was observed at a MoO3 layer thickness of 60 nm, which was determined by studying the dependency of the heterojunction short-circuit current on the thickness of the MoO3 layer.

DFT Studies of p-N,N-(Dimethylamino) Benzoic Acid with Para or Meta–Electron Withdrawing or Donating Moieties for Dye-Sensitized Solar Cells (DSSCs)

Solar energy is receiving considerable attention worldwide. Our contribution here focuses on fabricating p-N,N-(dimethylamino) benzoic acid (4-DMABA) donor-π-acceptor derivatives for use in dye-sensitized solar cells (DSSCs). The gas-phase and solvated 4-DMABA and some of its electron donating or withdrawing ortho or meta derivatives were studied theoretically. Density functional theory (DFT) and time-dependent DFT (TD-DFT) were applied to visualize their structural, molecular, photoelectrical, electronic, and photophysical parameters. The parameters for monitoring DSSC efficacies include HOMOs, LUMOs, energy gaps, wavelengths, oscillator strengths, light harvesting efficiencies (LHE), electron injection driving forces (ΔGinject), regeneration driving forces (ΔGregen), open circuit voltages (VOC), and short-circuit current densities (Jsc).

A novel K3WO2F5·2H2O:Mn4+ phosphor with excellent hydrophobic stability by coating paraffin wax for the application of WLEDs

Novel narrow-band red-emitting K3WO2F5·2H2O:Mn4+ and its paraffin wax (PW)-coated phosphor (K3WO2F5·2H2O:Mn4+@PW) were synthesized via simple co-precipitation method. Optical properties of the phosphors have been systematically analyzed. Meanwhile, the energy transfer process in the phosphor was discussed in detail, which provides a feasible basis for broadening the application range of the phosphor when excited by UV-light. The thermostability of K3WO2F5·2H2O:Mn4+ sample was analyzed via investigating the temperature-dependent photoluminescence properties. More importantly, the luminescence properties and hydrophobic stability of the phosphors coated with PW were superior to those of K3WO2F5·2H2O:Mn4+ and K2SiF6:Mn4+. The luminescence intensity of K3WO2F5·2H2O:Mn4+@PW decreased by only 24.5% after the phosphor was immersed in water for 360 min. K3WO2F5·2H2O:Mn4+@PW was used as red component to fabricate the warm white light-emitting diode, which presents excellent photoelectric parameters Ra = 90.1 and CCT = 3664 K) and remarkable stability in the range of 20–200 mA driving current. These results demonstrated that K3WO2F5·2H2O:Mn4+@PW red composition has the ideal application value in WLEDs.

Geometric Optimization of Perovskite Solar Cells with Metal Oxide Charge Transport Layers.

Perovskite solar cells (PSCs) are a promising area of research among different new generations of photovoltaic technologies. Their manufacturing costs make them appealing in the PV industry compared to their alternatives. Although PSCs offer high efficiency in thin layers, they are still in the development phase. Hence, optimizing the thickness of each of their layers is a challenging research area. In this paper, we investigate the effect of the thickness of each layer on the photoelectric parameters of n-ZnO/p-CH3NH3PbI3/p-NiOx solar cell through various simulations. Using the Sol–Gel method, PSC structure can be formed in different thicknesses. Our aim is to identify a functional connection between those thicknesses and the optimum open-circuit voltage and short-circuit current. Simulation results show that the maximum efficiency is obtained using a perovskite layer thickness of 200 nm, an electronic transport layer (ETL) thickness of 60 nm, and a hole transport layer (HTL) thickness of 20 nm. Furthermore, the output power, fill factor, open-circuit voltage, and short-circuit current of this structure are 18.9 mW/cm2, 76.94%, 1.188 V, and 20.677 mA/cm2, respectively. The maximum open-circuit voltage achieved by a solar cell with perovskite, ETL and HTL layer thicknesses of (200 nm, 60 nm, and 60 nm) is 1.2 V. On the other hand, solar cells with the following thicknesses, 800 nm, 80 nm, and 40 nm, and 600 nm, 80 nm, and 80 nm, achieved a maximum short-circuit current density of 21.46 mA/cm2 and a fill factor of 83.35%. As a result, the maximum value of each of the photoelectric parameters is found in structures of different thicknesses. These encouraging results are another step further in the design and manufacturing journey of PSCs as a promising alternative to silicon PV.