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Lead halide hybrid solar cells have demonstrated exceptional performance in recent years, but concerns over their toxicity and instability have spurred the development of perovskite-based cells without lead. This work explores a lead-free perovskite material consisting of cesium tin-germanium triiodide solid solution perovskite (CsSn0.5Ge0.5I3) is utilized to fabricate solar cells with varying thicknesses and donor densities of the absorber layer. The results imply that enhancing the thickness of the layer boosts the power conversion efficiency (PCE) by facilitating better photon absorption. However, this increase in thickness also causes a reduction in both the open-circuit voltage (VOC) and fill factor (FF). In other words, while thickening the layer improves PCE through increased photon absorption, it also negatively impacts other key performance metrics, such as VOC and FF. Conversely, the effect of donor density (Nd) on the cell's performance is less significant than the CsSn0.5Ge0.5I3 layer's thickness. This study sheds light on the critical role of thickness and donor density in optimizing the performance of CsSn0.5Ge0.5I3-based solar cells. The performance of c-Si and CIGS-based single junction bottom cells under standalone conditions is also analyzed using JV and EQE curves. The C-Si-based single junction solar cell exhibited greater efficiency (21.28%) in converting photons of different wavelengths into electrons compared to the CIGS-based solar cell (16.26%). Lastly, for increasing the PCE of the single-junction solar cells the study moves towards multi-junction solar cells. In this context, two highly efficient TSCs (LFPVK/c-Si and LFPVK/CIGS) are designed and analyzed using the current matching technique, which involves the series connection of the top and bottom cells with increased PV parameters (LFPVK/c-Si-JSC: 21.44 mA/cm2, VOC: 1.45 V, FF: 82.17%, PCE: 25.54% and LFPVK/CIGS-JSC: 21.83 mA/cm2, VOC: 1.33 V, FF: 73.34%, PCE: 21.45%). [ABSTRACT FROM AUTHOR]

Tandem solar cells have the potential to be more efficient than the Shockley–Queisser limit imposed on single junction cells. In this study, optical and electrical modeling based on experimental data were used to investigate the possibility of boosting the performance of kesterite/c-Si tandem solar cells by inserting an alternative nontoxic TiO2 buffer layer into the kesterite top subcell. First, with SCAPS-1D simulation, we determined the data reported for the best kesterite (CZTS (Eg = 1.5 eV)) device in the experiments to be used as a simulation baseline. After obtaining metric parameters close to those reported, the influence on the optoelectronic characteristics of replacing CdS with a TiO2 buffer layer was studied and analyzed. Different top subcell absorbers (CZTS0.8Se0.2 (Eg = 1.4 eV), CZTS (Eg = 1.5 eV), CZTS (Eg = 1.6 eV), and CZT0.6Ge0.4S (Eg = 1.7 eV)) with different thicknesses were investigated under AM1.5 illumination. Then, to achieve current matching conditions, the c-Si bottom subcell, with an efficiency at the level of commercially available subcells (19%), was simulated using various top subcells transmitting light calculated using the transfer matrix method (TMM) for optical modeling. Adding TiO2 significantly enhanced the electrical and optical performance of the kesterite top subcell due to the decrease in parasitic light absorption and heterojunction interface recombination. The best tandem device with a TiO2 buffer layer for the top subcell with an optimum bandgap equal to 1.7 eV (CZT0.6Ge0.4S4) and a thickness of 0.8 µm achieved an efficiency of approximately 20%. These findings revealed that using a TiO2 buffer layer is a promising way to improve the performance of kesterite/Si tandem solar cells in the future. However, important optical and electrical breakthroughs are needed to make kesterite materials viable for tandem applications. [ABSTRACT FROM AUTHOR]

This study presents a novel method to fabricate scalable photovoltaic fibers (PVFs) by leveraging crystalline silicon (c‐Si) solar cell technology, known for its high‐power conversion efficiency (PCE), stable performance, and low cost. The c‐Si PVF is built on a flexible circuit strip as narrow as 400 µm, and c‐Si cells as small as 0.35 mm2 are surface‐mounted on the strip. The cells are diced from an interdigitated back‐contact c‐Si solar cell (≈153 cm2). A c‐Si PVF including a 1 mm2 cell reaches PCE up to 9.6% and 11.0% under simulated AM 1.5G illumination without and with encapsulation, respectively, the highest reported for c‐Si PVFs, while a 1.5 ft‐long fiber produces ≈37 mW m−1. Additionally, the PVF can tolerate bending fatigue with no sign of performance loss after 8000 bending cycles. To demonstrate practical applicability, the c‐Si PVFs are also woven into textile swatches. They deliver ≈10 mW cm−2 under a halogen lamp and successfully power a light‐emitting‐diode. This PVF technology is scalable with regards to both achieving thin fibers and its compatibility with roll‐to‐roll fabrication processes. The fiber concept presented here can also be extended to any chip‐scale surface mountable devices, enabling cell‐agnostic fiber technologies for multifunctional electronic textiles. [ABSTRACT FROM AUTHOR]

Generation of hydrogen is very important, as it is one of the most desired alternatives to fossil fuels. Moreover, designing of cheap and stable electrocatalysts is the task for the efficient generation of hydrogen with reasonable activity. Materials hybridization can be considered a tool for engineering different material properties. Composites of modified silicon such as C–Si, Ni/(C–Si), Pt/(C–Si), and Pt–Ni/(C–Si) were prepared (in weight percent) and studied as electrocatalysts for the hydrogen evolution reaction (HER) in 0.5 M H2SO4 solution. The surface morphologies and chemical compositions of the composites were confirmed using transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy-dispersive X-ray analysis (EDX), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), X-ray fluorescence analysis (XRF), elemental mapping, and BET surface analysis. The electrochemical measurements of linear sweep voltammetry (LSV), Tafel plots, chronoamperometry, and electrochemical impedance spectroscopy (EIS) were used to study the behaviour of the prepared electrodes toward the hydrogen evolution process. Among the various prepared composites, [7%Pt–3%Ni]/[C–Si (1:1)] composite shows the best catalytic activity with the highest HER rate (940.95 µA cm−2 s−1), the lowest overpotential [0.358 V vs. (Ag/AgCl) ≈ 0.161 V vs. (RHE)] at 10 mA cm−2, and the lowest charge transfer resistance (2.657 Ω) compared to other prepared electrodes. In addition, it gives the highest values of 4.219 × 10−3 s−1 turn over frequency (TOF) and 642 mA g−1 mass activity. It shows good stability towards the hydrogen evolution reaction as the current density reaches about 34.28 mA cm−2 after 5 h. [ABSTRACT FROM AUTHOR]

A simple method for obtaining SiO2:Ag:Si and Ag:Si hybrid nanostructures is presented. High-temperature annealing of an Ag island film on the surface of c-Si makes it possible to preserve the plasmonic properties of Ag nanoparticles and protect them from external influences by coating them with a thermally grown layer of SiO2. The calculation of the electric field strength distribution in the structure with embedded Ag nanoparticles in c-Si demonstrates the presence of intrinsic "hot spots" at the corners of the nanoparticles, which leads to a maximum enhancement factor (~106) of Raman scattering. A numerical calculation of the dependence of the spectral position of a localized plasmon resonance on the geometry of structures can serve as a basis for their design in the future. Surface-enhanced Raman scattering showed reliable detection of the methyl orange from an aqueous solution at a concentration of <10–5 M. [ABSTRACT FROM AUTHOR]

The classification of photovoltaic technologies into generations aims at facilitating the overview and equally can support the identification of future trends. The initial definition by Martin Green follows the historical development, which however does not necessarily need to imply that a certain technology is old or outdated. To find an update of that early graph without immediately refusing the initial classification, first, the representation is filled with up‐to‐date numbers. Despite several new definitions of generations being introduced, these merely stay on a general level without quantitative justification. Here, in contrast, classification is further strengthened by numbers of the latest efficiency records and module prices. By becoming specific, it is possible to draw the current picture, compare it to the initial idea and reveal novel trends and potential. Showing different representations of the quantitative values further allows setting a focus of investigation and looking at the situation from various perspectives. In this way, it is expected to support the discussion not just of classification but rather of future technology potential, which becomes apparent from parallel trends. In addition, the importance of advanced optical designs for future competitive efficiency enhancement will be presented. [ABSTRACT FROM AUTHOR]

The power conversion efficiency of all-inorganic Sb2S3-on-Si two-terminal (2-T) monolithically integrated and four-terminal (4-T) mechanically stacked tandem solar cells are investigated. A one-dimensional solar cell capacitance simulator (SCAPS-1D) has been used to simulate the stand-alone antimony trisulfide (Sb2S3) top sub-cell, silicon (Si) bottom sub-cell, 2-T monolithic, and 4-T mechanically stacked tandem solar cells. The stand-alone sub-cells are optimized by extensive studies, including interface defects density, bulk defects density, absorber layer thickness, and series resistance. The power conversion efficiency (PCE) of simulated stand-alone sub-cells is compared and verified with the existing literature. A current matching condition is established to characterize the 2-T monolithic Sb2S3-on-Si tandem cell. A filtered spectrum has been utilized for bottom sub-cell measurement in the tandem solar cells. The best-simulated PCE of Sb2S3-on-Si 2-T monolithic and 4-T tandem cells is 30.22% and 29.30%, respectively. The simulation results presented in this paper open an opportunity for the scientific community to consider Sb2S3 as a potential top sub-cell material in Sb2S3-on-Si tandem solar cells with high PCE. [ABSTRACT FROM AUTHOR]

The current study introduces a two-terminal (2T) thin-film tandem solar cell (TSC) comprised of a polymer-based top sub cell and a thin crystalline silicon (c-Si) bottom sub cell. The photoactive layer of the top sub cell is a blend of PDTBTBz-2F as a polymer donor and PC71BM as a fullerene acceptor. Initially, a calibration of the two sub cells is carried out against experimental studies, providing a power conversion efficiency (PCE) of 9.88% for the top sub cell and 14.26% for the bottom sub cell. Upon incorporating both sub cells in a polymer/Si TSC, the resulting cell shows a PCE of 20.45% and a short circuit current density (Jsc) of 13.40 mA/cm2. Then, we optimize the tandem performance by controlling the valence band offset (VBO) of the polymer top cell. Furthermore, we investigate the impact of varying the top absorber defect density and the thicknesses of both absorber layers in an attempt to obtain the maximum obtainable PCE. After optimizing the tandem cell and at the designed current matching condition, the Jsc and PCE of the tandem cell are improved to 16.43 mA/cm2 and 28.41%, respectively. Based on this TCAD simulation study, a tandem configuration established from an all thin-film model may be feasible for wearable electronics applications. All simulations utilize the Silvaco Atlas package where the cells are subjected to standard one Sun (AM1.5G, 1000 W/m2) spectrum illumination. [ABSTRACT FROM AUTHOR]

Numerical simulation of single junction and tandem solar cells-based copper indium gallium diselenide Cu(In,Ga)Se2 and silicon (c-Si) electrical characteristics have been accomplished by Solar Cell Capacitance Simulator (SCAPS 1-D) tool. The layered structure consisting of CIGS as top cell with a buffer layer of zinc-based oxysulfide Zn(O,S) and the bottom cell of c-Si junction has been investigated. The top and bottom single cells have demonstrated the conversion efficiency as 11.63 and 13.16%, respectively. The tandem designs exhibited a conversion efficiency of 25.68% resulted from the enhanced open-circuit voltage (VOC) as 0.90 V and short-circuit current density (JSC) as 36.99 mA/cm². The cells were illuminated via AM 1.5 to investigate the current densities and external quantum efficiency (EQE). The simulations were optimized by adjusting the CIGS concentration and the thickness of semiconducting layers. Moreover, the effect of variation in temperature on the device performance has been investigated. [ABSTRACT FROM AUTHOR]

Monolithic hybrid halide perovskite/crystalline silicon (c-Si) tandem solar cells have demonstrated their great potential to surpass the theoretical efficiency limit of single-junction devices. However, the stability of perovskite sub-cells is inferior to that of the c-Si solar cells that have been commercialized, casting serious doubt about the lifetime of the entire device. During device operation, light and heat are inevitable, which requires special attention. Herein, we review the current understandings of the intrinsic stability of perovskite/c-Si tandems upon light and/or heat aging. First, we summarize the recent understandings regarding light facilitated ion migration, materials decomposition, and phase segregation. In addition, the reverse bias effect on the stability of tandem modules caused by uneven illumination is discussed. Second, this review also summarizes the thermal-induced degradation and mismatch issue, which underlines the system design of perovskite/c-Si tandems. Third, recent strategies to improve the intrinsic stability of perovskite/c-Si tandems under light and/or heat are reviewed, such as composition engineering, crystallinity enhancement, interface modification, material optimization, and device structure modification. At last, we present several potential research directions that have been overlooked, and hope those are helpful for future research on perovskite based tandem solar cells. [ABSTRACT FROM AUTHOR]

Crystalline silicon solar cells produced by doping processes have intrinsic shortages of high Auger recombination and/or severe parasitic optical absorption. Dopant-free carrier-selective contacts (DF-CSCs) are alternative routines for the next generation of highly efficient solar cells. However, it is difficult to achieve both good passivating and low contact resistivity for most DF-CSCs. In this paper, a high-quality dopant-free electron-selective passivating contact made from ultra-low concentration water solution is reported. Both low recombination current (J0) ~10 fA/cm2 and low contact resistivity (ρc) ~31 mΩ·cm2 are demonstrated with this novel contact on intrinsic amorphous silicon thin film passivated n-Si. The electron selectivity is attributed to relieving of the interfacial Fermi level pinning because of dielectric properties (decaying of the metal-induced gap states (MIGS)). The full-area implementation of the novel passivating contact shows 20.4% efficiency on a prototype solar cell without an advanced lithography process. Our findings offer a very simple, cost-effective, and efficient solution for future semiconductor devices, including photovoltaics and thin-film transistors. [ABSTRACT FROM AUTHOR]

Numerical simulation of single junction and tandem solar cells-based copper indium gallium diselenide Cu(In,Ga)Se2 and silicon (c-Si) electrical characteristics have been accomplished by Solar Cell Capacitance Simulator (SCAPS 1-D) tool. The layered structure consisting of CIGS as top cell with a buffer layer of zinc-based oxysulfide Zn(O,S) and the bottom cell of c-Si junction has been investigated. The top and bottom single cells have demonstrated the conversion efficiency as 11.63 and 13.16%, respectively. The tandem designs exhibited a conversion efficiency of 25.68% resulted from the enhanced open-circuit voltage (VOC) as 0.90 V and short-circuit current density (JSC) as 36.99 mA/cm². The cells were illuminated via AM 1.5 to investigate the current densities and external quantum efficiency (EQE). The simulations were optimized by adjusting the CIGS concentration and the thickness of semiconducting layers. Moreover, the effect of variation in temperature on the device performance has been investigated. [ABSTRACT FROM AUTHOR]

This study investigates the impact of Ultra-High Vacuum (UHV) Thermal annealing in a N₂/O₂ atmosphere on the passivation of Ar ion etched crystalline silicon (c-Si) surfaces. A comprehensive analysis of the resulting ultrathin Silicon OxyNitride Carbide layer (SiONC) was conducted using X-ray Photoelectron Spectroscopy (XPS), Ultra-Violet Spectroscopy (UPS), Photoluminescence Spectroscopy (PL), and Atomic Force Microscopy (AFM). XPS revealed a significant transformation in chemical composition from a carbon-rich contaminated surface SiO 1.02 C 2.98 to an oxygen- and nitrogen-containing passivated layer SiO 0.13 N 0.10 C 0.28. UPS measurements elucidated changes in the electronic structure and Fermi level position at the c-Si/SiONC interface. AFM imaging demonstrated the formation of non-uniform SiONC islands, influencing surface morphology. Notably, PL spectroscopy indicated enhanced orange and red luminescence with energies of 2.0 and 1.73 eV, respectively, attributed to the SiONC layer. The enhanced luminescence, coupled with improved thermal stability and oxidation resistance, positions the SiONC layer as a promising material for advancing the performance of silicon-based optoelectronic devices, such as solar cells and light-emitting diodes (LEDs). This study provides fundamental insights into the correlation between the chemical, electronic, and morphological properties of the SiONC layer and its potential for improving c-Si device performance. • Analyzed the impact of UHV thermal annealing in a N₂/O₂ atmosphere on the passivation of Ar ion-etched c-Si surfaces. • Identified the formation of an ultrathin SiONC layer with substantial changes in chemical composition. • Uncovered electronic structure modifications, including shifts in the Fermi level. • Observed the formation of non-uniform SiONC islands, influencing surface morphology. • Reported enhanced orange and red luminescence, attributed to the SiONC layer. [ABSTRACT FROM AUTHOR]

In this work, we demonstrate a comprehensive study of the optical properties of hemispherical Ag nanoparticles (AgNPs) on a single-crystal (c-Si) wafer. The fabricated method involves a galvanic displacement reaction of Ag on c-Si and annealing in oxygen atmosphere at 500 °C. Substrates with different morphological parameters of AgNPs were obtained by varying the volume ratio of Ag in the deposition solution. Using the quasinormal modes (QNMs) theory formalism, the localized surface plasmon resonance (LSPR) multipole positions were determined as a function of the AgNP size and incidence angle. Also, the effective field approximation and QNMs methods were used to calculate the specular reflectance of the disordered hemispherical array on c-Si. Thus, the experimentally obtained LSPR positions in the reflectance spectra were described. Finally, surface-enhanced Raman scattering (SERS) demonstrated reliable detection of brilliant green triphenylmethane dye (1 nM), methyl red dye (10 nM) and hemoglobin from bovine blood (1 mM). The dependence of the SERS enhancement factor on the LSPR position and the absorption band of the analyte was established, the maximum value of which was 1.1 × 10 7. In summary, this study suggests that the numerical and experimental investigation of the optical properties of hemispherical AgNPs on c-Si contributes to the field of optical sensing. [Display omitted] • Hemispherical AgNPs on c-Si have been fabricated by GDR and annealing in O 2. • Positions of the LSPR multipoles were determined using quasinormal modes (QNMs). • EFA and QNMs were used to calculate reflectance of the disordered AgNPs array on c-Si. • Dependence of EF on LSPR position and absorption band of the analyte was established. • SERS showed reliable detection of BG (1 nM) and MR (10 nM) solutions with EFs ∼ 10 7 and ∼ 10 6. [ABSTRACT FROM AUTHOR]

Since single junction c-Si solar cells are reaching their practical efficiency limit. Perovskite/c-Si tandem solar cells hold the promise of achieving greater than 30% efficiencies. In this regard, optical simulations can deliver guidelines for reducing the parasitic absorption losses and increasing the photocurrent density of the tandem solar cells. In this work, an optical study of 2, 3 and 4 terminal perovskite/c-Si tandem solar cells with c-Si solar bottom cells passivated by high thermal-budget poly-Si, poly-SiOx and poly-SiCx is performed to evaluate their optical performance with respect to the conventional tandem solar cells employing silicon heterojunction bottom cells. The parasitic absorption in these carrier selective passivating contacts has been quantified. It is shown that they enable greater than 20 mA/cm2 matched implied photocurrent density in un-encapsulated 2T tandem architecture along with being compatible with high temperature production processes. For studying the performance of such tandem devices in real-world irradiance conditions and for different locations of the world, the effect of solar spectrum and angle of incidence on their optical performance is studied. Passing from mono-facial to bi-facial tandem solar cells, the photocurrent density in the bottom cell can be increased, requiring again optical optimization. Here, we analyse the effect of albedo, perovskite thickness and band gap as well as geographical location on the optical performance of these bi-facial perovskite/c-Si tandem solar cells. Our optical study shows that bi-facial 2T tandems, that also convert light incident from the rear, require radically thicker perovskite layers to match the additional current from the c-Si bottom cell. For typical perovskite bandgap and albedo values, even doubling the perovskite thickness is not sufficient. In this respect, lower bandgap perovskites are very interesting for application not only in bi-facial 2T tandems but also in related 3T and 4T tandems.

In the preparation process of c-Si solar cells, qualified Si wafers must be processed through mechanical processing during manufacturing. Most of these processes involve mechanical processing, which inevitably results in severe mechanical damage layers and a wafer surface with large roughness. The current industry practice involves etching of the damage layer using an acid/alkali solution, and it is usually followed by deposition of additional passivation layers in the subsequent processes. However, even with these treatments, there still remain non-negligible microscopic saw damage and scratches on the wafer surface, which hinder the urgent development of a higher conversion efficiency of solar cells. Here, we provide a simple method to effectively suppress the impact of this surface damage. UV-OZONE treatment, which involves generation of an oxide layer and subsequent cleaning with hydrofluoric acid, leads to the effective regain of solar cell performance due to the passivation of dangling bonds and removal of sharp microstructures based on the creation of mechanical scratches. In addition, PEDOT:PSS/n-Si solar cells were prepared to exploit their strong surface dependence to investigate the effect of scratches on the overall performance. These results further validate the impact of scratches on solar cells, and a simple and effective method for surface damage suppression is provided.

Surface recombination loss limits the efficiency of crystalline silicon (c-Si) solar cell and effective passivation is inevitable in order to reduce the recombination loss. In this article, we have reviewed the prospects of aluminium oxide (Al2O3) as surface passivation material and associated process technologies are also addressed. Its underlined negative fixed charges, high process stability and process feasibility to use it in ultrathin films, make it exciting one as surface passivation material. Other materials used for passivation and their limitations are addressed. Relevant deposition techniques and their aspects are also discussed here. Ultrathin Al2O3 is generally produced by conventional Atomic Layer Deposition (ALD) methods. But slow deposition rate and low throughput made the ALD process limited its application in commercial solar industry. Plasma Enhanced Chemical Vapour Deposition (PECVD) is also used as alternative one but it suffers from high temperature process stability. Al2O3 deposited by Radio Frequency (RF) sputtering is found out to be one of the best deposition techniques because of its low cost and higher deposition rate. [ABSTRACT FROM AUTHOR]

In this study, we present the use of SiC/PVA composite thin films as downshifting layers (LDS) in order to improve the photoelectrical parameters of a Si-based solar cell. We showed that the adding of these layers increases the short circuit current density. This increase could surely lead to the improvement of the power conversion efficiency since the two parameters are relied. The J–V characterizations of the as made c-Si solar cell measured under white light showed an enhancement of the photocurrent after coating the c-Si solar cell with SiC-based LDSs. The same behavior was noticed upon exposure to UV light illumination which depended strongly on the elaboration conditions of the luminescent porous SiC particles. A decrease in total reflectance of the c-Si solar cell coated with SiC based LDS was also observed. Spectral Response measurements have shown significant enhancement where the solar cells have poor optical response. [ABSTRACT FROM AUTHOR]

Monolayer MoS2 is a promising semiconductor material for solar energy conversion application because of its excellent optoelectronic properties. In this study, monolayer n-type MoS2 / p-type c-Si heterojunction solar cell was proposed and simulated using AMPS software. The different factors influenced the photovoltaic performance of the solar cell were studied. The simulation results show that the solar cell can achieve the highest conversion efficiency of 22. 1% with the electron affinity of n-type MoS2 is 3. 75 eV, the doping concentration of n-type MoS2 is 1018 cm-3, and the doping concentration of p-type c-Si is 1017 cm-3. Finally, the influence of interface states at the n-type MoS2/p-type c-Si heterointerface on the overall performance of solar cell is simulated. It is found that the interface state density over 1011 cm-2·eV-1 will seriously affect the photovoltaic performance of solar cell. [ABSTRACT FROM AUTHOR]

Perovskite solar cells have become the main source of attraction among photovoltaic researchers since its inception in 2009 due to their steady enhancement in efficiency and cost-effective fabrication methodologies. The integration of the concept of multijunction or tandem technology with Perovskite solar cells is considered to be one of the best substitutes for designing efficient Solar Cells. Recently, the perovskite/silicon tandem architecture possesses tremendous research potential owing to their capability to generate competitive efficiencies. In this research article, we have analysed the optoelectronic properties of CsGeI 3 with the WIEN2K tool for first principle computations through the density functional theory methodology. The bandgap of CsGeI 3 is found out to be 1.6 eV. Calculated bandgap and absorption coefficient spectra are used as input parameters for device simulation using the SCAPS-1D tool. Environment-friendly CsGeI 3 and c-Si are used as top cell and bottom cell absorbers respectively with the two cells connected in series with an ITO interconnecting layer for the proposed tandem solar cell architecture. Under current matching scenario and AM 1.5G spectrum illumination, the standalone top cell shows PCE of 18.31 %, V oc ∼1.20 V, J sc ∼17.55 mA/cm2 and FF ∼86.42 % for 265 nm thick CsGeI 3 layer, while bottom cell when subjected to the spectrum transmitted by top cell, provided a PCE of 10.15 % with V oc ∼ 0.703 V, J sc ∼17.50 mA/cm2 and FF ∼82.62 % with 400 μm thick c-Si absorber. Before being implemented in the tandem configuration, simulated J-V characteristics of both top and bottom cells are calibrated to show close agreement with the experimental results. The two-terminal tandem device demonstrates an improved PCE of 28.43 %, FF of 84.90 %, J sc of 17.55 mA/cm2, and V oc of 1.90 V. The effect of R s and R sh and the interfacial and bulk defect states on the photovoltaic parameters (PCE, FF J sc , and V oc) is also analysed. Finally, a semi-analytical model is used to validate the J-V characteristics of the tandem architecture obtained with SCAPS-1D simulator using an equivalent circuit model of two series-connected diodes. This study can open new directions for the design of eco-friendly lead-free perovskite/c-Si based tandem devices with superior photovoltaic characteristics. • Investigation of the photovoltaic performance of CsGeI 3 -on- c -Si tandem solar cell using SCAPS-1D. • Electronic and optical properties of CsGeI 3 computed using WIEN2K within the framework of DFT. • The effect of series and shunt resistance, thickness, and defect density of CsGeI 3 on PV performance studied. • The tandem solar cell exhibited a PCE of 28.43 %, FF of 84.9 %, J sc of 17.55 mA/cm2, and V oc of 1.90 V. [ABSTRACT FROM AUTHOR]

The study of optical and plasmonic properties of structures is an important step in the development of substrates for surface-enhanced Raman scattering (SERS) applications. In this work, structures based on a disordered array of hemispherical silver nanoparticles (AgNPs) on a single-crystal silicon (c-Si) substrate are studied. A simple and reproducible method is proposed in which an Ag island film obtained by chemical reduction of AgNO 3 is transformed after annealing at 350 °C into an array of hemispherical AgNPs on a thin SiO 2 layer. The average radii of AgNPs range from 30 to 130 nm, which can be varied due to the concentration of AgNO 3 in the initial deposition solution. Numerical calculations of the scattering, absorption, and extinction cross-sections are used to determine the positions of the localized surface plasmon resonance (LSPR) multipoles depending on the hemispherical AgNP size. The splitting of the LSPR dipole is found in the reflection spectra at oblique angles of incidence for p-polarization of light, which indicates the prolate shape of the hemispherical AgNPs. Finally, SERS shows reliable detection of 10−7 M (crystal violet) with the enhanced factor ∼ 6.2 × 10 5 and the relative standard deviation of signal ∼ 10 %. These studies suggest that hemispherical AgNPs on a SiO 2 @c-Si are promising candidates for detecting triphenylmethane dyes. [Display omitted] • SERS substrates based on hemispherical AgNPs on SiO 2 @c-Si have been fabricated. • FDTD calculations were used to determine LSPR multipoles as a function of AgNP size. • Splitting of the LSPR in the reflection spectra of p-polarized light was found. • Prolate shape of the AgNPs were confirmed by SEM method and optical investigations. • SERS substrates showed reliable CV detection of 10−7 M with EF ∼ 6.2 × 10 5 and RSD ∼ 10 %. [ABSTRACT FROM AUTHOR]

PV windows can potentially produce electricity, reduce the air-conditioning load, and provide natural light. Cross-seasonal experimental tests for long period could eliminate the gap between real outdoor test and simulation estimation. In this research, the lighting-thermal-electricity performance of high-efficiency c-silicon PV windows was tested, and the improvement has been put forward according to the conditions. The long-term experiment was conducted cross different seasons, including summer, autumn, and winter seasons. The highest average power generation, 50W/m2, could be found in autumn. The average outside surface temperature of the PV window would reach 48 °C in sunny days in the autumn, which was higher than other seasons. Although the c-Si PV window maybe block the partial daylighting, the daylighting requirement still could be satisfied with the most days. Furthermore, the average Useful Daylight Illuminance was the highest in summer up to 0.79, and the average illumination uniform could be achieved at a high level in all seasons. For the improvement suggestions, some measures could be taken to reduce the indoor cooling load in summer. During winter, appropriate inner shading measures might be taken to prevent excessive illumination in the building, and allow the electricity and thermal performance of PV window.

In this work, we have optimized by simulation a solar cell n-c-Si(Sb)/p-c-Si structure, which is obtained by the recoil implantation of antimony (Sb) in crystalline silicon (c-Si). However the parameter structures (emitter thickness (Xj) for n-c-Si(Sb) layer, base thickness (Xb) for p-c-Si layer, donor doping concentration (Nd) and acceptor doping concentration (Na)) which have influences on the main solar cell characteristics like short-circuit current (J SC ), open-circuit voltage (V OC ), fill factor (FF) and efficiency (Eff) was taken into account. We suggest that a such component is more stable against unknown damages and will present a long life due to the annealing treatment at a high temperature (850°), which gives it a good stability. By using numerical method, all calculations have been carried out by developing a model to predicate the output parameters of the present pretended solar cell. Accordingly, with optimized structure parameters (N a = N d  = 10 17 cm −3 , Xj range from 0.05 to 0.1 μm and X b  = 300 μm) such solar cell presents an efficiency of 17.00% for AM 1.5 and 22.11% under sun concentration. For these reasons, the n-c-Si(Sb)/p-c-Si structure is considered as a promising solar cell component. [ABSTRACT FROM AUTHOR]

In this work, the effect of circular nanocavity on light trapping in a c-Si solar cell was studied by finite difference time domain (FDTD) simulation. The structure of the solar cell was considered to be Si3N4/c-Si/Ag, where the Ag layer was pattered and conformal growth of Si and Si3N4 was considered. The absorption spectra in the thin Si layer were determined and found 40 times higher at the infrared region (beyond 800 nm). For qualitative analysis, the short-circuit current of the solar cell was determined computationally by AM 1.5G solar illumination and found to be 2.1 times higher in the case of nanocavity as that compared to un-patterned solar cell. The enhancement in absorption in the solar cell is attributed to the different plasmonic modes coupled in the thin c-Si layer. The incident angle-dependent study was performed to observe the effect on enhancement in wide-angle incidence. The thickness-dependent study confirms 2.1 to 1.75 times enhancement in short-circuit current in 100- to 250-nm-thick c-Si layer. Therefore, this observation suggests that this structure has good prospect in achieving high conversion efficiency while reducing the device cost. [ABSTRACT FROM AUTHOR]

Abstract: A novel micro‐scale photovoltaic concept, Wafer Integrated Micro‐scale Photovoltaics (WPV), is proposed, analyzed, and experimentally demonstrated. The WPV concept seamlessly integrates multijunction micro‐cells with a multi‐functional silicon platform that simultaneously provides optical concentration, hybrid PV/CPV architecture, and mechanical alignment features. Fabrication and optical performance characterization of the Si platform are described in this paper. Over 100% improvement in the concentration‐acceptance‐angle product (CAP) is demonstrated using the wafer‐embedded micro‐concentrating elements, leading to significantly reduced module material and fabrication costs, sufficient angular tolerance for low‐cost trackers, and an ultra‐compact optical architecture compatible with commercial flat panel infrastructures. The development of a prototypical module with a 400× concentration ratio is described. Outdoor optical characterization of the module shows acceptance angles of ±1.7° and ±2.5° for 90% of on‐axis power and full‐width‐half‐maximum, respectively. The projected performance of the PV/CPV hybrid architecture illustrates its potential for cost‐effective collection of both direct and diffuse sunlight, thereby extending the geographic and market domains for cost‐effective PV system deployment. Leveraging low‐cost micro‐fabrication and high‐level integration techniques, the WPV approach presents a promising route to combine the high performance of multijunction solar cells and the low costs of flat‐plate Si PV systems. [ABSTRACT FROM AUTHOR]

In this work, a hafnium (Hf) thin film is introduced for the first time as the rear metallization scheme between the rear side of n‐type crystalline silicon (n‐Si) and Ag electrode in the poly (3, 4‐ethylenedioxythiophene) doped with poly (styrenesulfonate) (PEDOT:PSS) polymer/Si hybrid solar cell. Hf thin films are uniformly deposited at room temperature by sputtering technology, showing its advantages of stable electrical sheet resistance at the atmosphere with the relative humidity of 40%. The insertion of Hf thin film reduced interfacial carrier recombination and contact resistance loss, leading to a significant improvement in the open circuit voltage (Voc) and the fill factor (FF) of the polymer/Si hybrid solar cell. Eventually, compared with the reference device (only Ag back metallization), a higher power conversion efficiency (PCE) is obtained. This efficacy could be attributed to low work function of Hf thin film to ensure the highly transparent to electrons at the rear side of the hybrid solar cell. [ABSTRACT FROM AUTHOR]

We represent the photovoltaic performance of n-type crystalline silicon (n-Si) heterojunction with organic thin-layer (HOT) solar cell module using poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate)(PEDOT:PSS) together with 4,4′-cyclohexylidenebis [ N , N -bis(4-methylphenyl) benzenamine] (TAPC) as a protecting layer of PEDOT:PSS for air storage and barium hydroxide, Ba(OH) 2 as a hole blocking layer at the rear c-Si/cathode interface, respectively. PEDOT:PSS/n-Si front-junction solar cell showed a power conversion efficiency (PCE) of 13–14% (11–12%) with a short-circuit density, J SC of 29–31 mA/cm 2 (25–26 mA/cm 2 ), an open-circuit voltage, V OC of 0.62 V (0.625 V), and a fill factor, FF of 0.72 (0.704) for a 2 × 2 cm 2 (4 in.) size device. Solar cell module consisting of ten-units of series-connected 2 × 2 cm 2 (4 in.) sized cells exhibited a output power of 0.37 W (7.3 W) with a V OC of 6.1 V (6.2 V), a J SC of 0.084 A (1.78 A), and a FF of 0.712 (0.71). We also confirmed that it worked as a stand-alone photovoltaic system for remote monitoring of wireless camera drive. [ABSTRACT FROM AUTHOR]