Papers by Keyword: Solar Cell

Abstract: This study investigates the modeling and optimization of a single solar cell structure, utilizing the inorganic double perovskite Cs₂AuBiCl₆. This material features an A₂BB'X₆ composition and possesses a bandgap energy of 1.12 eV. The fundamental structure of the solar cell has been described, and the physical parameters of its primary layers have been outlined. A simulation model was developed to calculate the current-voltage characteristics and photovoltaic parameters, taking into account recombination rates due to defects within the absorber and at the interfaces with the electron transport layer (ETL) and hole transport layer (HTL). The influence of various parameters was analyzed, including bulk and interface density of defects, layer thicknesses, back contact work function and operating temperature. Additionally, the performance of structures with alternative transport materials for the ETL and HTL layers was evaluated. The impact of energy bandgap offsets with the absorbing perovskite layer was considered to identify materials that enhance the collection of photogenerated carriers and ultimately improve efficiency. The simulations revealed an optimized structure that demonstrated enhanced performance compared to the initial design. The optimized solar cell achieved a yield of 18.4 %, representing an increase of 5.4 % over the basic structure, with key performance metrics including, short-circuit current density Jsc = 36.75 mA/cm², fill factor FF = 76.76 %, open-circuit voltage V_oc = 0.5879 V. Given its narrow bandgap value, the optimized structure was further examined in a tandem cell configuration, showcasing its potential for high-efficiency devices with a yield reaching 33 %. This work significantly contributes to the development of efficient, stable, and non-toxic perovskite solar cells for photovoltaic applications, paving the way for advancements in sustainable energy technologies.

Abstract: As global climate change intensifies, a pivotal shift towards renewable energy sources becomes imperative. Given its adaptability and efficacy, solar cell technology stands out as a frontrunner in the quest to combat environmental degradation. With the vast expanse of buildings occupying significant portions of the urban landscape, integrating photovoltaics into building design is a timely necessity. Before embarking on tangible installations, conducting an energy simulation proves invaluable in gauging a building's energy requirements, ensuring cost and time efficiency. This paper delves into the advanced materials employed in solar cell technology and undertakes an energy simulation for a photovoltaic module. Building-Integrated Photovoltaics is not just an innovative leap in harnessing solar energy but also symbolizes the synergy between architectural design and energy production. By fine-tuning system operations and comprehending external factors, Building-Integrated Photovoltaics points to a future where energy solutions are both sustainable and tailored to a wide range of applications.

Abstract: In this paper, we examined CH₃NH₃PbI₃ potential as an absorber component for perovskite solar cells (PSCs). We used CuSCN (copper thiocyanate) as the hole transport layer and, ZnO as the electron transport layer to optimize work the device, in the CH₃NH₃PbI₃-based perovskite solar cell, and we used the solar cell capacitance simulator (SCAPS-1D). Exemplary perovskite solar cell is made up of six main layers, each of which is composed of a different material: glass, a thinning layer of fluorine-doped tin oxide substrate (FTO), ZnO for electron transport, CH₃NH₃PbI₃ for methylammonium lead iodide for the perovskite effective layer, copper thiocyanate for hole transport, and platinum (Pt) for the electrode. The best Optimized device structure, FTO / CuCSN /CH₃NH₃PbI₃ / ZnO /Pt, had a power conversion efficiency of 42.69%, according to simulation data. We examined the impact of changing thickness, defect density, and temperature on the efficiency of the device. The Optimum efficiency we get at thickness 10 μm is 42.69%, which is a promising result, Jsc is 29.766433 (mA/cm²), and FF is 91.39% and Voc is 1.5692 (V), best efficiency corresponds to defect density 1*. while, we note that the efficiency of perovskite solar cells decreases gradually at increase temperature.

Abstract: This work is focused on the study of photosensitive structures based on porous Si and film TiO₂, which are promising for solar energy. For numerical simulation of the transportation and accumulation of charge carriers in the considered heterostructure, the drift-diffusion approximation of the semiclassical approach was proposed. A device scheme of a solar cell model based on TiO₂/porous-Si/Si heterostructures is proposed. Production of photoconverters of solar cells based on the TiO₂/porous-Si/Si heterostructure can be carried out according to the standard method supplemented by additional technological operations. Ohmic contacts are formed in the upper and lower parts of the structure above the TiO₂ and Si layers. The strip system of contacts is a contact grid, with hatching, the surface coefficient should not exceed 5%. The thickness of the applied layer of photoresist should be 1 μm. Using the PC1D program, the light characteristics of the fabricated structure were calculated (open circuit voltage V_OC, short circuit current I_SC, fill factor FF and efficiency η), and current-voltage characteristics were plotted. The influence of the thickness and doping level N_d and N_a of porous Si and TiO₂ layers on the productivity of a heterojunction solar cell TiO₂/porous-Si/Si was studied in order to obtain a device with a good conversion efficiency. It was found that the energy conversion efficiency of a TiO₂/porous-Si/Si solar cell can reach 22.5 %. Based on the optimized simulation conditions, it was found that the maximum solar cell efficiency is achieved at thicknesses of 100 and 200 nm and donor concentration of N_d=1∙10¹⁷ cm^-3 and acceptor concentration of N_a=1∙10¹⁸ cm^-3 for TiO₂ and porous Si buffer layer, accordingly.

Abstract: The solar light radiation causes some of the heat to be trapped inside the solar cell that raises the solar cell’s temperature, then reduces the electrical efficiency of the overall system. The thermal radiation from solar light causes overheating on the solar cell surface and degrades its functionality. In this study, the thermal insulation coating has been proposed to prevent interior trapped heat. Different nanocoating systems have been developed using nano-Titanium Dioxide (TiO₂) namely T1B2 and T2B2, nano-Zinc Oxide (ZnO) namely Z1B2 and Z2B2 and nano-Tin Oxide (SnO) namely S1B2 and S2B2. All the nanoparticles have been synthesized at various weight percentages which are 20wt.% and 60wt.% in the B2 binder system, Methyltrimethoxysilane (MTMS) / nitric acid (HNO₃). The incorporation of nanoparticles increases the hydrophobicity of binder coating in which the Water Contact Angle (WCA) of coating improves up to 105°. The embedded nanoparticles increase the surface roughness, then reduce the contact of water to the substrate’s surface. Apart from that, the coating is also capable to halt the drastic increment in surface temperature. The result has shown that the B2 binder coating increases the surface temperature of solar cell by 2.54°C after 1hr of Xe 1000 W/m² irradiation. The raise in temperature is due to the strong oxidation of nitric acid. However, the incorporation of nano-ZnO and nano-SnO in B2 binder matrix capable to reduce the temperature of the solar cell. The wide bandgap of both nanoparticles induces good stability of coating at high operating temperature. The Z1B2 and S2B2 has reduced the temperature of solar cell by 7°C and 3°C, indicating their great thermal insulation property for solar cell application.

Abstract: In this paper, the influence of anti-solvents on the properties of cesium bismuth iodide (CBI – Cs₃Bi₂I₉) perovskite solar cells (PeSCs) that were dripped with different anti-solvents, i.e., isopropanol, chlorobenzene (CB), and toluene during the spin-coating process was evaluated. Scanning electron microscopy images visually depicted the presence of extremely flat and homogeneous film with highly compactness for the Cs₃Bi₂I₉ fabricated with isopropanol compared to other anti-solvents. A strong absorption band was observed at around the wavelength of 500 nm for all the CBI films, and we found that the maximum absorption percentage reached as high as 85%, while the current-voltage measurement showed that the CBI film fabricated with isopropanol showed twenty-one times increment than CB, in terms of power conversion efficiency and short circuit current density. Our findings suggest a further improvement of CBI film morphology by the anti-solvent for enhanced morphology and better solar cell performance in the future.

Abstract: The a-C/a-C:B homojunction of palmyra sugar has been successfully fabricated using the nanospray method. Palmyra sugar was chosen as the main source of carbon because it is cheap, renewable, abundant and available around the clock. nanospray is used as a deposition method on glass ITO substrates because of several advantages, namely cheap, easy, portable, low power consumption, the deposited layer is more evenly distributed and thinner. Junction samples when in bright conditions [emitted light] showed an increase in current and voltage values ​​compared to dark conditions. Testing the current and voltage of the junction sample shows the characteristics of a rectifier diode. This confirms the results of the test using PES as a doping process with amorphous carbon with boron capable of changing the conduction type from a-C from an intrinsic semiconductor to a p-type semiconductor. Testing the junction sample when irradiated with visible light using a lamp shows symptoms of the photovoltaic effect. Tests directly on the sun when conditions AM 1.5 samples showed symptoms of the photovoltaic effect. This indicates that the a-C/a-C:B amorphous carbon homojunction junction sample functions as a solar cell.

Abstract: Photoelectrochemical cell (PEC) has the same working principle as solar cell which convert solar energy into electricity. PEC consists of photoanode, electrolyte, and counter electrode, where electrolyte plays an important role in determining PEC performance. Yttria-stabilized zirconia (YSZ) is the most suitable electrolyte used due to its high ionic conductivity and chemically stable. In this study, YSZ was deposited to ZnO Nanorods (NRs) by doctor blade method with thickness variation of 100 μm (PEC10) and 120 μm (PEC12). X-ray diffraction (XRD), scanning electron microscope (SEM), and UV-Vis spectroscopy were used to distinguish the phase, morphology, and band gap of the formed materials, respectively. Moreover, I-V test was also conducted to evaluate the performance of the fabricated PEC with different YSZ thickness. SEM image confirmed the deposition thickness of YSZ layer on NRs which formed rough and irregular interface due to grain boundary fusion of YSZ and NRs. In addition, there is little difference XRD pattern from PEC10 and PEC12 which shows ZnO and YSZ peaks with peak shifting observed. Meanwhile, slightly difference noticed on band gap value where PEC10 has 3.25 eV and PEC12 has 3.58 eV. Even though, the characteristic of PEC10 and PEC12 is similar, the I-V test shown a significant difference of solar efficiency where PEC10 has higher efficiency of about 0.328% than PEC12. This difference is contributed by smaller grain size which has higher specific surface area and porosity. Based on this study, the thickness of electrolyte layer YSZ doesn’t affect the basic characteristic of PEC but affect the efficiency of PEC significantly.

Abstract: In this work, the impacts of wafer doping type on structural and optical properties of black silicon (b-Si) fabricated by metal-assisted chemical etching (MACE) process are investigated. P-type and n-type mono-crystalline silicon (mono c-Si) wafers are etched in an aqueous solution of hydrofluoric acid (HF), silver nitrate (AgNO₃) and deionised water (DI H₂O) at room temperature and various durations from 5-20 minutes. Surface morphological results demonstrate the formation of b-Si nanowires (NWs) with average lengths of 0.4-0.8 μm for p-type wafers and 0.8-3.0 μm for n-type wafers. The higher length of the NWs for the n-type wafers is due to the minority charge carriers, which lead to a higher etching rate during the MACE process. Within the 300-1100 nm wavelength region, weighted average reflection (WAR) for the p-type and n-type wafers decreases to 6.6% and 6.4%, respectively, after 20 minutes of etching. The corresponding improvement in broadband light absorption results in maximum potential short-circuit current density (J_{sc (max)}) of 38.2 and 38.8 mA/cm² for the p-type and n-type b-Si, respectively, which is an of enhancement of 39.9% and 42.1% when compared to the J_{sc (max)} of planar c-Si reference.

Abstract: The study of amorphous semiconductors is of great interest because they find important applications in many electronic devices, like large area solar cells and photosensors. We have developed a methodology for the analysis of transient response of amorphous photodiodes when switched off from steady-state and when they are exposed to a δ pulse of light. For this purpose continuity equations and the transit time effect have been calculated. For the p-i-n photodiodes, characteristics of photo current decay have been analyzed for an ideal case in which the diode is assumed to have a unit current gain. It is found that characteristics either due to decay from steady-state or due to light pulse excitation is transit time dominated. The short-circuit performance of solar cells resembles to a p-i-n diode because a solar cell is essentially a p-i-n diode which is used as an energy converter. Thus short circuit current decay of solar cells behaves similar to the photocurrent decay of the diode and the same method of analysis can be applied.