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Antireflection coatings (ARCs) increase the absorption of light and, therefore, the conversion efficiency of solar cells. Mullite was chosen as the ARC material for a silicon (Si) solar cell and was synthesized by melting a charge consisting of a mixture of Al2O3 and SiO2 at a component concentration of 75 and 25 wt.%, respectively. It has been established that the integral reflection (RS) of ARCs based on mullite is about 6.0 times less than for silicon and about 2.5 times less than the RS of a coating based on silicon nitride. The electric characteristics measured by a solar simulator before and after vacuum deposition of a mullite film with a thickness of 80–85 nm on solar-cell samples showed an increase of short-circuit current up to 49.5% and a rise in efficiency up to 6.8%. [ABSTRACT FROM AUTHOR]

Black silicon has attracted significant interest for various engineering applications, including solar cells, due to its ability to create highly absorbent surfaces or interfaces for light. It enhances light absorption in crystalline solar cells, improving the efficiency of converting incident light into electricity for photovoltaic applications. This research focused on fabricating nanostructures that played a critical role in enhancing light absorption in the upper layers of solar cells. These nanostructures were created using the black silicon method, forming a layer known as "black silicon". The coating not only improved the efficiency of crystalline solar cells but also enhanced their stability. The antireflection coating, composed of nanostructures with various shapes, including conical, pillar-like, and spike-like forms, achieved a reflectivity as low as 10% in the spectral range of 400–700 nm. This corresponded to a sample with α = 0.85 and a chuck bias of 4 W. An Inductively Coupled Plasma Reactive Ion Etching (ICP RIE) machine was employed to develop and control the specific shape, size, and density of the fabricated black silicon, which was then subjected to testing. The efficiency of the black silicon photovoltaic cell was 23.3%. [ABSTRACT FROM AUTHOR]

Indoor organic photovoltaics (IOPVs) with tunable absorption spectra and relatively high power conversion efficiency (PCE) have emerged as one of the most promising energy sources for Internet of Things devices, but enhancing the device performance under various directions of indoor illumination is challenging. Herein, it is proposed to combine omnidirectional optical engineering and ternary strategy for achieving high‐performance IOPVs. The advantage is taken of a ternary bulk heterojunction (BHJ) with a polymer donor having aligned absorption spectra with the light‐emitting diode (LED) spectrum and a guest component that not only blueshifts the near‐infrared absorption of the acceptor but also improves electrical and morphological properties of the BHJ. A 2D photonic‐structured antireflection coating is further developed to selectively improve the light absorption of IOPVs, leading to a PCE of 29.07% under 1000 lux LED illumination. More importantly, the antireflection coating maintains the initial PCE even when irradiated by light incident at large angles, demonstrating an omnidirectional effectiveness. This weaker angular dependency on light absorption provides practical prospects for future sustainable indoor photovoltaic systems. [ABSTRACT FROM AUTHOR]

Solar cells technology will be one of the futuristic major resources for global energy demands. One of the major problems in energy harvesting using solar cells was reflection of incident light over solar cell surface. The present research work aims to synthesize the magnesium fluoride through sol-gel process which acts as antireflection layer for achieving better output performance. MgF 2 films were deposited over solar cells at varying time periods of 60, 90, 120 and150 min through electrospraying technique. MgF2 electrosprayed solar cells were inspected for evaluating its structural, optical, electrical and morphological characteristics. The coated solar cells were analyzed under dark and light conditions. The precursor materials involved in sol-gel synthesis of MgF 2 were magnesium chloride hexahydride, polyethylene glycol and hydrofluoric acid. From the I–V results, it is evident that performance of 120 min MgF 2 coated solar cell exerts maximum performance of 19.38 % (open) and 19.41 % (controlled). MgF 2 antireflective electrosprayed films were prominent materials for minimizing reflection and ensuring the maximum photon transmission into the coated surface especially in opto-electronic applications. [Display omitted] [ABSTRACT FROM AUTHOR]

The Solar cell efficiency is crucial, and optical losses can hinder it significantly. Anti-reflective coatings are effective in minimizing these losses. In our study, we used Fresnel equations to calculate reflectance values for single-layer SiO2, ZrO2, a SiO2-ZrO2 mixture, and a double-layer SiO2/ZrO2 configuration. We then assessed their impact on crystalline silicon solar cells using the SCAPS program. The reflectance values of single-layer SiO2, ZrO2 and 10%SiO2-90%ZrO2 mixture were calculated as 19.17%, 13.09% and 13.01%, respectively. Notably, the double-layer SiO2/ZrO2 coating showed a low reflectance of 7.58%, a significant improvement compared to uncoated silicon at 37.45%. Efficiency values for crystalline silicon solar cells were calculated for single layer as 18,95% (SiO2), 20.39% (ZrO2), 20,40% (mixed coating) respectively and 21.68% for the double-layer SiO2/ZrO2 configuration.

This study focuses on the fabrication and characterization of a transparent conductive window with high transmission properties. The window is created by depositing optimized antireflection layers on quartz glass to emphasize the spectral range of 450–800 nm at an incidence angle of 35°. The deposition process involves an antireflection layer to minimize reflection and achieve a transmission level above 91% within the specified spectral range. The thin film demonstrates the excellent optical properties of the fabricated transparent conductive window, making it suitable for a wide range of applications requiring high transmission and resistance to laser-induced damage. This research provides insights into the fabrication and performance of transparent conductive windows, laying the groundwork for potential applications in optics and industrial settings. [ABSTRACT FROM AUTHOR]

Due to the remarkable progress in photovoltaic technology, enhancing efficiency and minimized the costs have emerged as global challenges for the solar industry. A crucial aspect of this advancement involves the creation of solar cell antireflection coating, which play a significant role in minimizing sunlight reflection on the cell surface. In this study, we report on the optimization of the characteristics of CeO2 films prepared by pulsed laser deposition through the variation of laser energy density. The deposited CeO2 nanostructure films have been used as an effective antireflection coating (ARC) and light-trapping morphology to improve the efficiency of silicon crystalline solar cell. The film's thickness increases as laser fluence increase. The refractive index of the antireflective film is measured as a function of laser fluence. The properties of CeO2 thin films' were characterized by various techniques. X-ray diffraction measurements show the grown films were crystalline with cubic and hexagonal phases. The degree of crystallinity of the film increases with the increase in the laser fluence. Scanning electron microscope results reveal that the film's morphology and film uniformity improved as the laser fluence increases. Raman shift of the CeO2 film as a function of laser energy density was investigated. Photovoltaic properties show that the conversion efficiency of the silicon solar cell increases from 8.37 to 14.04% after deposited with ARC CeO2 film at laser energy density of 76.39 J/cm2. The CeO2 films deposited at 76.39 J/cm2 laser pulse energy density have highest hydrophobicity among all the prepared samples. [ABSTRACT FROM AUTHOR]

The Solar cell efficiency is crucial, and optical losses can hinder it significantly. Anti-reflective coatings are effective in minimizing these losses. In our study, we used Fresnel equations to calculate reflectance values for single-layer SiO2, ZrO2, a SiO2-ZrO2 mixture, and a double-layer SiO2/ZrO2 configuration. We then assessed their impact on crystalline silicon solar cells using the SCAPS program. The reflectance values of single-layer SiO2, ZrO2 and 10%SiO2-90%ZrO2 mixture were calculated as 19.17%, 13.09% and 13.01%, respectively. Notably, the double-layer SiO2/ZrO2 coating showed a low reflectance of 7.58%, a significant improvement compared to uncoated silicon at 37.45%. Efficiency values for crystalline silicon solar cells were calculated for single layer as 18,95% (SiO2), 20.39% (ZrO2), 20,40% (mixed coating) respectively and 21.68% for the double-layer SiO2/ZrO2 configuration. [ABSTRACT FROM AUTHOR]

Use and performance criteria of photonic devices increase in various application areas such as information and communication, lighting, and photovoltaics. In many current and future photonic devices, surfaces of a semiconductor crystal are a weak part causing significant photo-electric losses and malfunctions in applications. These surface challenges, many of which arise from material defects at semiconductor surfaces, include signal attenuation in waveguides, light absorption in light emitting diodes, non-radiative recombination of carriers in solar cells, leakage (dark) current of photodiodes, and light reflection at solar cell interfaces for instance. To reduce harmful surface effects, the optical and electrical passivation of devices has been developed for several decades, especially with the methods of semiconductor technology. Because atomic scale control and knowledge of surface-related phenomena have become relevant to increase the performance of different devices, it might be useful to enhance the bridging of surface physics to photonics. Toward that target, we review some evolving research subjects with open questions and possible solutions, which hopefully provide example connecting points between photonic device passivation and surface physics. One question is related to the properties of the wet chemically cleaned semiconductor surfaces which are typically utilized in device manufacturing processes, but which appear to be different from crystalline surfaces studied in ultrahigh vacuum by physicists. In devices, a defective semiconductor surface often lies at an embedded interface formed by a thin metal or insulator film grown on the semiconductor crystal, which makes the measurements of its atomic and electronic structures difficult. To understand these interface properties, it is essential to combine quantum mechanical simulation methods. This review also covers metal-semiconductor interfaces which are included in most photonic devices to transmit electric carriers to the semiconductor structure. Low-resistive and passivated contacts with an ultrathin tunneling barrier are an emergent solution to control electrical losses in photonic devices. [ABSTRACT FROM AUTHOR]

Investigation and development of the post-growth technology for fabricating multi-junction photovoltaic converters based on GaInP/GaInAs/Ge heterostructure has been carried out. Antireflection coating, ohmic contacts and mesa- structure forming stages have been reviewed. The technology of n+-GaAs contact layer etching with the help of plasma-chemical, liquid and ion-beam etching has been investigated. Antireflection coefficient of radiation from the heterostructure with TiOx/SiO2 (x close to 2) antireflection coating surface was less then 3% in wavelength range 450–850 nm. The value of contact resistance for n- and p-type conductivity was 3 × 10–5–3 × 10–6 Ω cm2, the decrease of photosensitive region shading degree at increased bus-bar conductivity has been archived. The mesa-structure surface current leakage decreased to the value of 10–9 A at voltage less then 1 V. [ABSTRACT FROM AUTHOR]

In this study, we aim to minimize light loss and achieve high power conversion efficiencies (PCE) in perovskite solar cells (PSCs) by employing a spectral conversion film component with antireflection properties. In our scheme, NaYF4:Tm, Yb, and Gd luminescent nanorod/silica nanosphere-based thin films are applied on CH3NH3PbI3 PSCs to improve the device efficiency. The film was fabricated by spin coating an aged silica sol containing NaYF4:Tm, Yb, and Gd luminescent nanorods. The size and the spectral conversion properties of the NaYF4:Tm, Yb, and Gd luminescent nanorods were controlled by tuning the Gd3+ ion concentration. The microstructure and the transmittance properties of the thin film were controlled by changing the concentration of NaYF4:Tm, Yb, and Gd luminescent nanorod in silica sol. The thin films have excellent spectral conversion properties while exhibiting a maximum transmittance. The photovoltaic performance of PSCs with NaYF4:Tm, Yb, and Gd luminescent nanorod/silica nanosphere-based thin films was systematically investigated. The light transmittance was optimized to 95.1% on a cleaned glass substrate, which resulted in an average increase of about 3.0% across the broadband range of 400–800 nm. The optimized films widen the spectrum of light absorbed by conventional PSC cells and reduce reflections across a broad range, enhancing the photovoltaic performance of PSCs. As a result, the PCE of the PSC increased from 14.51% for the reference device without a thin film to 15.67% for the PSC device with an optimized thin film. This study presents a comprehensive solution to the problem of Fresnel reflection and spectral response mismatch of the PSCs, which provides new ideas for the light management of PSCs. [ABSTRACT FROM AUTHOR]

In this study, considering the good optical properties of CeO2 thin films, their anti-reflective effect on crystalline silicon solar cells was investigated. First molarity and then coating speed optimizations were carried out for the optimum thickness value. In addition, annealing temperature and annealing time optimizations were performed on CeO2 thin films, and the appropriate values for annealing temperature and annealing time were determined. As a result of all optimizations, it was found that 0.3 M concentration, 6000 rpm coating speed, 400 °C annealing temperature, and 120 min annealing time were optimum values for CeO2 thin films. The average reflectance value of CeO2 thin films obtained using these values was 14.32%, while the minimum reflectance value was 0.62%. When the optimum reflectance values were applied to c-Si solar cells with Afors-het simulation, it was observed that the efficiency value increased from 11.57 to 16.89% compared to the uncoated solar cell. [ABSTRACT FROM AUTHOR]

The article describes the results of a research on the surface morphology and optical properties of Al2O3, ZnO, and TiO2 thin films deposited by atomic layer deposition (ALD) for applications in silicon solar cells. The surface topography and elemental composition were characterised using a scanning electron microscope, and thickness was determined using an optical reflectometer. The samples were structurally examined using a Raman spectrometer. The structural variant was identified: for Al2O3 it is sapphire, for TiO2 it is anatase, and for ZnO it is wurtzite. Possibilities of minimising light reflection using single and double thin film systems below 5% were presented. For the first time, the effectiveness of these thin films on the current-voltage characteristics and electrical parameters of manufactured silicon solar cells was examined and compared. The solar cell with the highest efficiency of converting solar radiation into electricity was obtained for Al2O3/TiO2 and the efficiency of such a photovoltaic device was 18.74%. [ABSTRACT FROM AUTHOR]

Theoretical investigations of the dependence of the optimal thickness of a one-layer antireflection SiO coating on a silicon photodiode on the characteristics of the light incident to the photodiode. It is shown that the optimal thickness of the one-layer antireflection SiO coating for different angular distributions of intensity increases the quantum efficiency of the photodiode by up to 1.1 times in comparison with the classical one-layer antireflection coating with a thickness , which is optimal in the case of the normal incidence of monochromatic light. [ABSTRACT FROM AUTHOR]

In the current context, there is a great desire to develop renewable energy sources as a power source. In order to improve the power conversion efficiency (PCE) of silicon solar cells, several studies are being undertaken in this area. This investigation focuses on preparing ZnO-Al2O3 blend as an antireflective coating (ARC) for improving the efficiency of polycrystalline silicon power conversion. The sol—gel method was employed to synthesis ZnO-Al2O3 blend which is produced by mixing zinc oxide with aluminium oxide. The spin coating process was used to deposit single to four layers of ZnO-Al2O3 blend on a silicon solar substrate. The thickness of ZnO-Al2O3coating obtained was measured with the help of atomic force microscopy (i.e.40 nm).The effect of zinc oxide and aluminium oxide coating on electrical, structural and optical characteristics of coated polycrystalline silicon solar cells, as well as cell temperature is investigated. A layer deposition of a single to multiple layers on a silicon solar cell was identified by an increase in layer thickness. At a low cell temperature (40 °C), the triple layer(LIII)deposition attained a maximum absorbance of 92% and power conversion efficiency (PCE) of 18.8%, demonstrating that photons diffuse on the solar cells were increased. The results show that zinc oxide and aluminium oxide mixture is a good anti-reflection coating material in improving silicon solar cell power conversion efficiency. [ABSTRACT FROM AUTHOR]

The manufacturing technology and the results of measurements of current–voltage characteristics of ITO/SnO2/CdS/CdTe/Ag thin-film solar cells both without antireflection coating and with antireflection coating are presented. The material for the antireflection coating was obtained by melting the composition of MgF2 : CaF2 fluorides in a solar furnace at a component ratio of 55 : 45 (wt %). It is shown that the deposition of an antireflection coating on the outer surface of thin layer solar cells increased their efficiency to ~2.0%. [ABSTRACT FROM AUTHOR]

The internal quantum efficiency (IQE) is given as the ratio between the externally collected electron current and the photon current absorbed by the device. Spectral analysis of IQE measurements is a powerful method to identify performance‐limiting mechanisms in solar cells. It also enables the extraction of key electrical and optical parameters. However, the potential of IQE measurements is only rarely fully utilized, presumably due to the significant complexity associated with the fitting process and its sensitivity to noise. In this study, machine learning is proposed as an efficient method to extract quantitative information from IQE measurements. The extraction method is automated and easy to use, providing an array of specific device parameters. By simplifying the analytical process, the developed machine learning algorithms also extract the parasitic absorption of the antireflection coating, a key parameter that is difficult to obtain by traditional methods. Although the method has been developed for and tested on silicon solar cells, it can be adapted and applied to other types of solar cells. [ABSTRACT FROM AUTHOR]

In this paper, the impact of pyramidal texture on a silicon substrate in ZnO/p-Si heterojunction was investigated. The texturisation of p-type silicon (100) substrate was obtained using the KOH anisotropic wet chemical etching method for different etching times. The RF magnetron sputtering technique was used to deposit ZnO thin films on textured Si substrates and planar Si substrates to form ZnO/Si heterojunction. The surface morphology was studied with field emission scanning electron microscopy (FE-SEM) and atomic force microscopy (AFM). Optical properties were investigated using UV-Visible spectroscopy and photoluminescence (PL). The results show that the PL intensity in the visible region of the electromagnetic spectrum increases with the etching time, while a significant reduction is observed in the reflectance. Due to impressive anti-reflection response, ZnO/Si (textured silicon-TS) heterojunction can be effective in improving the efficiency of solar cells.

In this paper, the electron beam vacuum coating method was used to coat a SiO2 film on an MgAl2O4 spinel substrate. The thickness of the coating was aimed to be 925 nm based on the physics of the antireflection coatings. Atomic force microscope images revealed that the coated silica was 880 nm thick, which is close to the aimed theoretical thickness and had 2.11 nm roughness. It could enhance the transparency of the spinel substrate by being coated on it. The infrared transmittance of the sample coated with SiO2 film in the range of 3700 nm‐4800 nm was measured by a Fourier transform infrared spectrometer and reached 92.5% to 78.5%, which was about 2%–4% higher than that of MgAl2O4 spinel. In addition, it was discovered that the bonding force between the coating and the substrate is determined to be about 200 MPa. The results of this study can be used for further precise design and production of antireflection coatings on the transparent materials that need more transparency. [ABSTRACT FROM AUTHOR]

In recent years, with the development of wearable electronics, the demands for high-performance photodetectors with smaller size, lower power consumption, and higher sensitivity have increased remarkably. Photodetectors based on one-dimensional (1D) zinc oxide (ZnO) nanowires (NWs) have been intensively investigated owing to their geometrical nanostructure possessing a large surface-to-volume ratio, high carrier mobility, and adjustable optical absorption. However, ZnO NW photodetectors usually can only detect ultraviolet (UV) light, limiting their application in the field of photodetection. In this paper, a heterojunction photodetector (HPD) based on ZnO/CuO/NiO (ZCN) core–shell–shell NWs is reported. The nanoscale copper oxide (CuO) film is deposited on hydrothermally grown ZnO NWs as the visible light absorber. The nanoscale nickel oxide (NiO) shell layer is uniformly coated on the surface of ZnO/CuO NWs by spin coating, which improves the detection capability of the photodetector in the range of UV-to-visible (UV–vis) significantly. Benefited from the large light absorption area provided by the 1D nanostructure and the type II band alignment, the ZCN NW HPD shows a fast response (rise/decay 0.12/0.22 s) and a large sensitivity of 18.65 mA/W under UV irradiation at a 0 V bias. Experimental and simulation results show the key role of NiO shell layer in ZCN NW HPD. Our results suggest core–shell–shell heterojunction nanostructures to develop high-performance photodetectors for next-generation UV–vis broadband photosensing applications. [ABSTRACT FROM AUTHOR]

In this work, an anti-reflection coating was prepared in the region (400-1000) nm of wavelength, with a double layer of silicon dioxide (SiO2) as an inner layer and the second layer of the mixture (SiO2) and titanium dioxide (TiO2) with certain ratios, as an outer layer using the chemical spraying method with a number of 6 sprays of layer SiO2 and 12 sprays of layer SiO2 - TiO2. Using the method of chemical spraying deposited on the glass as a substrate with a different number of sprays of SiO2, and a fixed number of TiO2-SiO2. The optical and structural properties were determined using UV-Vis spectroscopy and atomic force microscopy (AFM). The results show that by using a mixed layer, the optimal optical performance of a broadband low-reflection ARC (anti-reflection coating) was obtained. The work also reports the comparison of experimental and theoretical results with the help of MATLAB, which relies on the characteristic matrix along the visible region – near-infrared.

Perovskite solar cells (PSCs) are getting popular as promising photovoltaic technology due to their high efficiency and economical manufacturing costs. PSCs' effectiveness and stability have continuously improved in recent years, and research into minimizing lead leakage and creating environmentally acceptable lead-free perovskites is advancing the commercialization of PSCs step by step. The goal of this paper is to design a solar cell model based on getting higher light transmission and lower light reflection. Three-layer solar cell structure containing perovskite, titanium dioxide, and metal Nano layer sandwich between a silicon substrate and glass cover. The Maple 17 software is used to create the numerical results for the Transfer matrix, which determines the transmission and reflection of the incident light for various physical parameters of the structure. The results showed that the cell with aluminum cell has an excellent transmittance for a wide range of incident angles, perovskite thickness, and effective layer thickness. The short circuit current density reaches the most significant value at (α = 0), and it has zero value for parallel incidents. The cell of CH3NH3PbI3perovskite type and the aluminum metal nanolayer has the highest current density and a non-zero value for a wide range of incident angles. [ABSTRACT FROM AUTHOR]

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Current mismatch due to solar cell failure or partial shading of solar panels may cause a reverse biasing of solar cells inside a photovoltaic (PV) module. The reverse-biased cells consume power instead of generating it, resulting in hot spots. To protect the solar cell against the reverse current, we introduce a novel design of a self-protected thin-film crystalline silicon (c-Si) solar cell using TCAD simulation. The proposed device achieves two distinct functions where it acts as a regular solar cell at forward bias while it performs as a backward diode upon reverse biasing. The ON-state voltage (VON) of the backward equivalent diode is found to be 0.062 V, which is lower than the value for the Schottky diode usually used as a protective element in a string of solar cells. Furthermore, enhancement techniques to improve the electrical and optical characteristics of the self-protected device are investigated. The proposed solar cell is enhanced by optimizing different design parameters, such as the doping concentration and the layers' thicknesses. The enhanced cell structure shows an improvement in the short-circuit current density (JSC) and the open-circuit voltage (VOC), and thus an increased power conversion efficiency (PCE) while the VON is increased due to an increase of the JSC. Moreover, the simulation results depict that, by the introduction of an antireflection coating (ARC) layer, the external quantum efficiency (EQE) is enhanced and the PCE is boosted to 22.43%. Although the inclusion of ARC results in increasing VON, it is still lower than the value of VON for the Schottky diode encountered in current protection technology. [ABSTRACT FROM AUTHOR]

In this paper, we investigate the effects of aluminum oxide (Al2O3) antireflection coating (ARC) on silicon heterojunction (SHJ) solar cells. Comprehensive ARCs simulation with Al2O3/ITO/c-Si structure is carried out and the feasibility to improve the short circuit current density (JSC) is demonstrated. Based on the simulation results, we apply Al2O3 ARC on SHJ solar cells, and the increasement in JSC to 1.5 mA/cm2 is observed with an Al2O3 layer thickness of 20 nm. It is because the total reflectance of SHJ solar cells is decreased by the shifting of the wavelength range on constructive and destructive light interference. As a result, we believe that the proposed Al2O3 ARC can support an effective engineering technic to increase JSC and efficiency of SHJ solar cells. [ABSTRACT FROM AUTHOR]

Optically transparent zinc oxide and tantalum pentoxide thin surface films were deposited on front surface of polycrystalline silicon solar cell in the presence of room temperature for minimizing the incident light reflection. The deposition may be performed through vacuum or non-vacuum-based coating techniques. In this current research work, radio frequency sputter deposition technique was adopted for achieving uniform surface coatings such as zinc oxide (ZnO), tantalum pentoxide (Ta2O5) and zinc oxide–tantalum pentoxide blends (ZnO–Ta2O5). Antireflective surface coatings enhance light transmission and improve the power conversion efficiency of solar cells. The coated and uncoated solar cells were analysed to study the structural, optical, electrical, morphological and thermal characteristics. The existence of ZnO, Ta2O5 and ZnO–Ta2O5 blends were confirmed by matching the standard diffraction pattern with the obtained X-ray diffraction (XRD) data. The average crystallite size determined from obtained XRD analysis was 24.15 nm. ZnO (G1), Ta2O5 (G2) and ZnO–Ta2O5 blends (G3) were coated over solar cell under optimal sputter coating time of 45 min. ZnO–Ta2O5 blend-coated solar cell (G3) exhibited maximum photocurrent and voltage generation of Jsc = 36.9 mA cm−2, Voc = 0.666 V (under direct sunlight) and Jsc = 40.02 mA cm−2 and Voc = 0.671 V (under simulated light source). Through field-emission scanning electron microscopy (FESEM) analysis, cross-sectional thickness of various samples were identified as 0.55, 0.61 and 0.63 µm. From experimental results, the blend-coated solar cell (G3) was found to be promising antireflective coatings for multicrystalline Si solar cells. Neodymium light was significant in replicating consistent solar radiation, especially for promoting growth in green plants and domestic animals. [ABSTRACT FROM AUTHOR]

We report high-quality TiO 2 and TiO 2 -PMMA composite thin films prepared by sol-gel process for application in optical coatings. The addition of PMMA to the TiO 2 sol exhibits significant improvements in the optical quality and morphology of the TiO 2 films. A comparison between TiO 2 and TiO 2 -PMMA composite thin films is described with respect to various optical properties and their application in optical coatings for high-energy laser applications. The refractive index and bandgap of TiO 2 are tailored by controlling the TiO 2 sol: PMMA volume ratio. The refractive index varies in the range of 2.4 to 2.0 at 550 nm by controlling the TiO 2 : PMMA composition. Incorporation of PMMA leads to reduction in absorption from 1000 ppm to 20 ppm in the composite films, which is attributed to passivation of defect states. In addition, incorporation of PMMA into the TiO 2 sol results in the filling of voids and a significant improvement in surface figure (from λ/6 to λ/10) of the composite films. These properties collectively enhance the laser induced damage threshold (LIDT) of 2.1 J/cm2 for TiO 2 film to 17 J/cm2 of the TiO 2 -PMMA composite film. LIDT mechanisms in the films are discussed. Demonstration of antireflection coatings (AR) as well as high reflection coatings (HR) exhibiting wavelength tuning of the reflection peak using TiO 2 -PMMA composite thin films, is presented. An AR coating @1200 nm with 11.5 J/cm2 LIDT is reported. [Display omitted] • TiO 2 -PMMA composite thin films with LIDT 9.4 J/cm2 prepared using Sol-gel. • Refractive index is tunable in the range of 2.4–2.0 using TiO 2 -PMMA composite. • Addition of PMMA reduces absorption, stress, voids in the film significantly. • High reflection and antireflection coating demonstrated using composite thin films. • Wavelength tunability of optical coatings demonstrated using the composite material. [ABSTRACT FROM AUTHOR]

In this study, the antireflection effect of CdS and ZnO/CdS layers was investigated via computing and solar cell I-V graphs and efficiency of the solar cell is simulated using the SCAPS. The lowest average reflectance value for single layer CdS was calculated as 13.43 %, for ZnO/CdS double layer 9.46 %. The efficiency values of CdS/p-Si/p+-Si and ZnO/CdS/p-Si/p+-Si heterojunction solar cells were calculated by changing the CdS and ZnO thicknesses from 40 nm to 80 nm. The highest efficiency value for the CdS/p-Si/p+-Si structure was calculated as 20.30 %. The efficiency value for the ZnO/CdS/p-Si/p+-Si heterojunction solar cell was increased to 21.82 % with the effect of the ZnO layer.

The effects of single-layer antireflection coatings (SLARCs) on the performance of crystalline silicon (c-Si)-based solar cells have been analyzed numerically. In this study, amorphous (a-WO3) and crystalline (c-WO3) tungsten trioxide was introduced as a SLARC to investigate the performance of photovoltaic cells. Different antireflection coating (ARC) materials including aluminum trioxide (Al2O3), magnesium fluoride (MgF2), titanium dioxide (TiO2), magnesium oxide (MgO), silicon carbide (SiC), silicon dioxide (SiO2), aluminum-doped zinc oxide (AZO), strontium fluoride (SrF2), and titanium nitride (TiN) were used for simulative comparative analysis with WO3 in the search for the highest efficiency of c-Si solar cells. The PC1D simulator was employed to investigate the impact of these ARC materials on device performance. When compared to other ARC materials, the highest efficiency (η) of 19.35% was achieved for a-WO3 thin film with a thickness of 70.7 nm. The a-WO3 ARC layer yielded an open-circuit voltage (Voc) of 0.6363 V, short-circuit current density (Jsc) of 36.86 mA/cm2, and short-circuit current (Isc) of 3.686 A. The Jsc values obtained are in close agreement with the ARC layers' reflectance values. It is important to recognize that the main factors established in this simulation study about SLARC production will make experimental data cheaper and faster. [ABSTRACT FROM AUTHOR]

Antireflection coatings (ARCs) are crucial components of high‐efficiency solar cells. A new ARC design philosophy, dubbed high‐low refractive index stacks, has demonstrated good potential to minimize reflection losses for triple‐junction and quadruple‐junction solar cells in simulations. We have implemented such novel ARCs on GaInP/InGaAs/Ge triple‐junction solar cells and compared the experimental performances—external quantum efficiency and reflectivity—with that of identical devices equipping the classic double‐layer ARC. For typical materials such as MgF2/ZnS with ambient glass, the results show that the new design improves the short circuit current by 1.8% at normal incidence and 1.6% and 1% for angles of incidence of 30° and 50°, respectively. [ABSTRACT FROM AUTHOR]

The antireflection coating (ARC) suppresses surface light loss and thus improves the power conversion efficiency (PCE) of solar cells, which is its essential function. This paper reviews the latest applications of antireflection optical thin films in different types of solar cells and summarizes the experimental data. Basic optical theories of designing antireflection coatings, commonly used antireflection materials, and their classic combinations are introduced. Since single and double antireflection coatings no longer meet the research needs in terms of antireflection effect and bandwidth, the current research mainly concentrates on multiple layer antireflection coatings, for example, adjusting the porosity or material components to achieve a better refractive index matching and the reflection effect. However, blindly stacking the antireflection films is unfeasible, and the stress superposition would allow the film layer to fail quickly. The gradient refractive index (GRIN) structure almost eliminates the interface, which significantly improves the adhesion and permeability efficiency. The high-low-high-low refractive index (HLHL) structure achieves considerable antireflection efficiency with fewer materials while selecting materials with opposite stress properties improves the ease of stress management. However, more sophisticated techniques are needed to prepare these two structures. Furthermore, using fewer materials to achieve a better antireflection effect and reduce the impact of stress on the coatings is a research hotspot worthy of attention. [ABSTRACT FROM AUTHOR]

Herein, the structures of three types of silver nanoparticles embedded within the rear antireflection layer of silicon bifacial solar cells are investigated by performing a three-dimensional simulation based on the finite-element method. Regarding aesthetics, impressive colours are achieved with an optical gain by using plasmonic nanoparticles with a size of approximately 10 nm, which are usually considered to be unbeneficial to solar cells. The rear optical spectra and short-circuit current gain/loss of the solar cells are analysed, well reproducing the main performance features observed in the previous experiment. The underlying mechanism is that the hybrid plasmonic antireflection coating layer presents particular interference patterns modulated due to the dramatic plasmonic resonance, which compensate for the absorption loss in particles for certain structure parameters. These results pave the way towards the application of plasmonic particles with a much smaller size and open up a road for designing efficient colourful building integrated photovoltaics. [ABSTRACT FROM AUTHOR]

Transition-edge sensors (TES) are remarkable superconducting devices for a wide range of radiation detection with the ability of both energy resolution and counting photons. For the detection of single photons at telecom wavelength, optical Ti/Au bilayer TESs are fabricated and characterized. The superconducting transition temperature (Tc) of the Ti/Au films is effectively tuned from 162 to 72 mK by increasing the relative thickness ratio between the Au and Ti layer. The sensitive area is 20 μm × 20 μm, on which an SiO2/SiNx antireflection structure is coated by an ICP-PECVD process. The TES device shows an energy resolution of 0.19 eV and can discriminate up to 36 incident photons, with an effective time constant around 107 µs at 95 mK. [ABSTRACT FROM AUTHOR]

In this paper, the impact of pyramidal texture on a silicon substrate in ZnO/p-Si heterojunction was investigated. The texturisation of p-type silicon (100) substrate was obtained using the KOH anisotropic wet chemical etching method for different etching times. The RF magnetron sputtering technique was used to deposit ZnO thin films on textured Si substrates and planar Si substrates to form ZnO/Si heterojunction. The surface morphology was studied with field emission scanning electron microscopy (FE-SEM) and atomic force microscopy (AFM). Optical properties were investigated using UV-Visible spectroscopy and photoluminescence (PL). The results show that the PL intensity in the visible region of the electromagnetic spectrum increases with the etching time, while a significant reduction is observed in the reflectance. Due to impressive anti-reflection response, ZnO/Si (textured silicon-TS) heterojunction can be effective in improving the efficiency of solar cells. [ABSTRACT FROM AUTHOR]

In this study, Magnesium Fluoride (MgF2) and Zinc Sulfide (ZnS) multi-layer antireflection coatings were prepared using Glancing Angle Deposition (GLAD) technique. MgF2 and ZnS materials have been coated in a Hind - Hivac coating unit (model 15F) on glass substrates. Antireflection coatings were prepared at different oblique incident flux angles (α = 40°, 65°,70°, 80°) by the thermal evaporation method. The Grazing incidence X-ray diffraction (GIXRD)analysis indicated that the thin films coated at different incident angles were crystallized in a single phase with an orthorhombic structure. The XRD results showed improvement of the film crystallinity upon grain size increment. Optical properties were investigated throughout the measurement of transmission spectra and refractive index and extinction in the visible region. The refractive index of films decreased from 2.8 to 1.66 as the flux angle increased from 40° to 80°. The extinction coefficient of films increased from 0.03849 to 0.05997 as the flux angle increased from 40° to 80°.

The power conversion efficiency (PCE) of single‐junction perovskite solar cells (PSCs) is being rapidly promoted towards their theoretical limit, with a certified value of 25.7%. Reducing optical loss will further contribute to PCE improvement. Here, the optical loss including reflection loss, absorption loss, and transmission loss in printable mesoscopic perovskite solar cells (p‐MPSCs) is analyzed. A printable mesoporous SiO2 antireflection coating for improving the transmittance of the fluorine‐doped tin oxide (FTO) glass substrate by reducing optical reflection at the air/glass interface is reported. With modulated porosity and thickness, the mesoporous SiO2 film constructs a graded refractive index interface and increases the transmittance of FTO glass by ≈2%–4% in the spectral range of 350–800 nm at normal incident angle with the highest transmittance improved from 85% to 89%. The SiO2 coating also exhibits wide‐angle and broadband antireflection properties. The coatings successfully help p‐MPSCs obtain about an average 3% enhancement in the short‐circuit current density (JSC) and PCE. This study demonstrates the necessity of optical management for efficient solar cells and provides a cost‐effective and scalable antireflection coating for the future realistic application of PSCs. [ABSTRACT FROM AUTHOR]

Titanium dioxide was extensively used in solar cell industry and currently has been studied to produce passivated contacts in PERC/PERT and TOPCon solar cells. The aim of this paper was to analyze the impact of the thickness of TiO2 thin films deposited by electro-beam evaporation on the weighted reflectance and the surface passivation on silicon solar cells. Thin films with different thicknesses were deposited to produce PERT solar cells, varying from 50 to 90 nm. The surface passivation was enhanced as the thickness was increased. For instance, at 400 nm, the internal quantum efficiency increased from 71% to 76% when the thickness of the TiO2 was augmented from 50 nm to 90 nm. The lowest weighted reflectance was obtained in samples with 80 nm thick TiO2 films. Considering the compromise between antireflection properties and surface passivation, the highest efficiency solar cells were produced with 80 nm thick TiO2.

• Developed an advanced antireflection coating using ICP-assisted magnetron sputtering. • Achieved high transmittance (>98.7 % at 420–720 nm) and enhanced scratch resistance. • Coatings exhibit low residual stress (∼680 MPa) and strong adhesion (LC3 ∼180 mN). • Gradient system reduces stress, leading to a more stable interface. Antireflection (AR) coatings with sapphire-like hardness are highly desired in various applications. Traditionally, hard AR coatings resist penetration, scratching, and abrasion by depositing a hard layer, such as silicon nitride (Si 3 N 4), with a 1 to 2 µm thickness. However, thick Si 3 N 4 thin films, fabricated by high-energy inductively coupled plasma assisted (ICP-assisted) sputtering, often introduce high residual stress, leading to severe buckling problems when the surface is scratched. To address these challenges, we employ a "Step up-step down" design method, integrating a hardness gradient structure with a series of SiO x N y films. This approach achieves high optical transmittance (Tave > 98.7 % at 420–720 nm), low residual stress (∼680 MPa), improved scratch resistance, and strong adhesion at the film-substrate interface (L C3 ∼180 mN). Our findings demonstrate significant potential for various mechanical and optical applications, including automotive and consumer electronics devices. [ABSTRACT FROM AUTHOR]

Al2O3/TiO2 thin films were deposited onto monocrystalline silicon surfaces using an atomic layer deposition. Their surface morphology and optical properties were examined for their possible use in solar cells. The surface condition and chemical composition were characterized using a scanning electron microscope and the thickness was measured using a spectroscopic reflectometer. The refractive index and the reflection characteristics were determined. First, the optical properties of the Al2O3 thin film and its influence on recombination in the semiconductor were examined. In this way, it can fulfil a double role in a solar cell. Since reflection reduction was only achieved in a narrow range, it was decided to use the Al2O3/TiO2 system. Thanks to this solution, the light reflection was reduced in a wide range (even below 0.2%). [ABSTRACT FROM AUTHOR]

[Display omitted] • Sputtering is used to fabricate a nitride/oxy-nitride/oxide tandem stack and sol–gel method is used to deposit an ormosil layer. • In ormosil layer, an organic moiety is introduced into inorganic network to impart improved mechanical properties, and to avoid pinholes and cracking. • The hybrid multilayer absorber exhibits very high thermal stability in air (500 °C for 1000 hrs) and vacuum (600 °C for 1000 hrs) for long durations. • Ormosil layer acts as a passivation layer on PVD coating and as an anti-reflection coating, thus improving thermal stability and optical absorption. We describe a hybrid multilayer solar absorber coating consisting of physical vapor deposited (PVD) Ti interlayer, aluminum titanium nitride (AlTiN) main absorber layer, aluminum titanium oxynitride (AlTiON) semi-absorber layer, aluminum titanium oxide (AlTiO) anti-reflection layer and sol–gel deposited ormosil passivation layer. The ormosil layer, which is essentially organically modified silica, also acts like an anti-reflection coating, thus, increasing the absorptance (α) of the multilayer stack to ∼ 0.950 (c.f., α = 0.930 for the PVD coating on stainless steel substrate) along with an emittance (ε) of 0.17@82 °C. Generally, pure inorganic sol–gel coatings like silica contain defects, which allow gases and corrosive substances to penetrate the coating/substrate interface, thereby, deteriorating the performance of the coating under extreme environments. However, the presence of an organic moiety in the inorganic network results in a dense microstructure with improved mechanical flexibility and hardness. We discuss in detail the effect of ormosil layer on the performance of the PVD deposited solar absorber coating. We report that the unique and stable microstructure of the ormosil layer helps in increasing the thermal stability of the underneath PVD coated solar absorber coating, particularly suitable for applications in concentrating solar collectors useful for solar steam generation. [ABSTRACT FROM AUTHOR]

The current research effort focused on enhancing the power conversion performance of silicon solar cells by minimizing the scattering of incident photons on the solar cell surface. This can be achieved through antireflective thin-film coatings. The main purpose of antireflective coatings is to minimize the reflection of incident light radiation. Silicon solar cells with antireflective thin-film coatings exhibit better light transmittance, and hence power conversion efficiency is improved. Metal chalcogenides are materials with a wider energy band gap and possess better electrical and optical properties. This study aims at using zinc selenide (ZnSe), a metal chalcogenide, as an antireflective coating material. ZnSe was synthesized through a room-temperature thermal evaporation technique. Further, coating of ZnSe on the silicon solar cell was done using an electrospraying technique. The optimal solar cell sample (D3) with thickness of 1.32 µm exhibited maximum transmittance of 95.8% in the visible spectrum. The electrical resistivity of the D3 sample under neodymium radiation was noted as 3.43 × 10−5 Ω m, which was lower than other coated samples. The output efficiency of the sample was found to be 19.95%, which was a 4.58% improvement over pristine solar cells. Based on the observations, it is evident that the synthesized ZnSe is a promising coating material for controlling reflection loss and increasing power conversion efficiency. [ABSTRACT FROM AUTHOR]

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