ABSTRACT
The most rapidly expanding type of solar cells are the Perovskite Solar Cells (PSCs), because of its high device performance, ease of synthesis, high open-circuit voltage, and affordability. Despite these advantages, the development of perovskite-based solar cells continues to be impeded by the issues with perovskite stability and the utilization of the hazardous heavy element lead (Pb). The study emphasizes on the bifacial structure that maintains the conventional absorber layer and electron transport layer (ETL) in the optimized PSC structure. This study employs SCAPS software for device simulation to comprehensively analyze how various parameters affect the performance of solar cells. Additionally, doping concentration variation in both ETL and HTL are explored. The simulation reveals that changing device structure from monofacial to bifacial significantly influences PSC performance, demonstrating that optimizing individual layers effectively enhances overall solar cell performance. The optimized structure achieves impressive PSC performance metrics through parametric analysis, such as voltage (VOC) of 1.18 V, fill factor (FF) of 82.24%, current density (JSC) of 27.12 mA/cm2, power conversion efficiency (PCE) of 27.90% for an incident solar spectrum from the ETL side, and power conversion efficiency (PCE) of 19.86% for an incident solar spectrum from the HTL side, the calculated bifaciality factor (BF) for this structure is 71.18%.
ABSTRACT
We report on the development of a multistacked configuration of a photonic cooler for implementation in sunny and arid regions. The optimized multistacking structure considers TiOx as a top layer, NiOx as the buffer layer, and Ag as a hot mirror (i.e., a reflective layer of the NIR light spectrum). The entire stacked layers were deposited in situ without breaking the vacuum. The oxide layers were grown reactively under an oxygen medium at a deposition pressure of 2 × 10-4 Torr. The level of TiOx surface wettability was demonstrated to be controlled by the oxygen flow during the film growth process, which may additionally provide a self-cleaning property to the IR filters. By combining low refractive index layers (i.e., TiOx) with the high refractive index of the metal oxides (i.e., NiOx) along with the metal layers (i.e., Ag, Al), the photonic filtration (i.e., cutoff) of the infrared spectrum was successfully achieved while keeping the light transmittance of the visible (vis) light above 50%. Different structures with different thicknesses have been systematically assessed, including TiOx/NiOx/Ag, TiOx/NiOx/Al, TiOx/MoOx/Ag, and TiOx/MoOx/Al. Furthermore, numerical simulations were carried out using SCAPS-1D and OptiLayer software to evaluate the application of these filters on silicon solar cells, considering the experimental electrical and optical parameters for each explicit layer of the device. Our results confirm that the development of such coatings with a scalable thin film growth process may have a real commercialization potential due to their multifunctionalities such as IR filtering, antireflection coating in the vis range, and antisoiling properties.
ABSTRACT
Areas with abundant sunlight, such as the Middle East and North Africa (MENA), are optimal for photovoltaic (PV) power generation. However, the average power loss of photovoltaic modules caused by dust accumulation is extreme and may reach 1%/day, necessitating frequent cleaning which adds to the cost of operations and maintenance. One of the solutions to the problem of PV soiling is to develop anti-soil coatings, where hydrophilic or hydrophobic coatings with spectral characteristics suitable for PV applications are added to the outer layer of PV glass. However, the effectiveness of such coatings depends extensively on climatic conditions and geographical locations. Since coatings add to the cost of solar panels, it is imperative that they are first tested for suitability at the intended location and/or in similar weather conditions prior to their large-scale deployment. This critical review focuses on various anti-dust technologies employed to mitigate the PV soiling issue. The in-depth comparison of the various developed techniques and materials aims at providing a relevant input in adapting the right technology based on particles' accumulation mechanism, weather conditions, and geographical location. Though the mechanical cleaning process is the most used solution to date, development of thin film anti-dust coating could be a better alternative-when it is relevant-due to its abrasion-free capability, large deployment, economic viability, and durability. This review aims at serving as a reference in this topic, thereby paving the way to adapting efficient anti-dust coatings, especially in the MENA region and/or desert environment at large, where it is the most relevant.
ABSTRACT
We report on the optical and morphological properties of silica thin layers deposited by reactive RF magnetron sputtering of a SiO2 target under different oxygen to total flow ratios [r(O2) = O2/Ar, ranging from 0 to 25%]. The refractive index (n), extinction coefficient, total transmission, and total reflectance were systematically investigated, while field-emission scanning electron microscopy, atomic force microscopy, and three-dimensional (3D) average roughness data construction measurements were carried out to probe the surface morphology. Contact angle measurements were performed to assess the hydrophilicity of our coatings as a function of the oxygen content. We performed a thorough numerical analysis using 1D-solar cell capacitance simulator (SCAPS-1D) based on the measured experimental optical properties to simulate the photovoltaic (PV) device performance, where a clear improvement in the photoconversion efficiency from 25 to 26.5% was clearly observed with respect to r(O2). Finally, a computational analysis using OptiLayer confirmed a minimum total reflectance of less than 0.4% by coupling a silica layer with n = 1.415 with another high-refractive-index (i.e., >2) oxide layer. These promising results pave the way for optimization of silica thin films as efficient antireflection and self-cleaning coatings to display better PV performance in a variety of locations including a desert environment.
