Renewable energy is in high demand, with significant contributions from the solar industry encouraging research into more efficient, cost-effective, and versatile solar cell technologies. Anti-reflection coating (ARC) is an important method for improving solar cell efficiency by minimizing light reflectance and maximizing photon absorption. This study investigates the electrical and optical behaviors of single- and double-layer ARCs for gallium arsenide (GaAs) solar cells, using PC1D simulation for single-layer SiO2, and ZnSe, and double-layer SiO2/ZnSe configurations. The findings indicate that the double-layer SiO2/ZnSe ARC structure significantly reduces reflectance and enhances light absorption, leading to a higher current density (Jsc) and overall efficiency. With optimized layer thicknesses of 60 nm (ZnSe) and 100 nm (SiO2), the efficiency increased from 20.628% to 30.904%, representing a 49.81% improvement. This enhancement is primarily attributed to the increased photon absorption and a higher electron–hole generation rate, confirming the superior performance of double-layer ARCs over single-layer configurations.

Anti-reflection coating (ARC) plays an important role in reducing the reflection of incident light and absorbing more photons to produce more photoelectrons. In this paper, a single-layer TiO2 anti-reflection coating is performed on GaAs solar cells. In the simulation study, we compared the solar cell before and after ARC by using PC1D simulation software. The I–V characteristics, reflectance, and external quantum efficiency have been simulated with a refractive index of 2.324 at 600 nm wavelength. The simulated results show that the ARC-coated solar cell performs better. It is found that the power conversion efficiency of 24.75% reflection is 9.5%, and the EQE is 95% at the 62 nm thickness of the ARC layer. The optimized reflectivity was found to be around 5%, which is quite lower than that without ARC (32%).

In this work, a numerical assessment of the optoelectrical properties of the ZnO–ZnSe–CdSe heterojunction for a thin and cost-effective solar cell was made by using the PC1D simulation software. The photovoltaic (PV) properties have been optimized by varying thicknesses of the absorber layer of the p-CdSe layer, the window layer of n-ZnSe, and the antireflection coating (ARC) layer of ZnO, a transparent conductive oxide with enhanced light trapping, and wide bandgap engineering. There is a positive conduction band offset (CBO) of ΔEc = 0.25 eV and a negative valence band offset (VBO) of ΔEv = 1.2 − 2.16 = − 0.96 eV. The positive CBO prevents the flow of electrons from the CdSe to the ZnSe layer. Further, the impact of doping concentration on the performance of solar cells has been analyzed. The simulation results reveal the increase in the efficiency of solar cells by adding an ARC. The rapid and sharp increase in the efficiency with the thickness of the window layer beyond 80 nm is interesting, unusual, and unconventional due to the combined effect of morphology and electronics on a macro-to-micro scale. The thin-film solar cell with the structure of ZnO/ZnSe/CdSe exhibited a high efficiency of 11.98% with short-circuit current (I sc ) = 1.72 A, open-circuit voltage (V oc ) = 0.81 V and fill factor (FF) = 90.8% at an optimized thickness of 2 μm absorber layer, 50 nm window layer, and 78 nm ARC layer. The EQE of solar cells has been observed at about 90% at a particular wavelength at 470 nm (visible light range). Around 12% of efficiency from such a thin-layered solar cell is highly applicable.

The PC1D simulation aand origin software were successfully used for the study of Carrier Lifetime and Temperature effect on InGaN Single-Junction Solar Cell. For the simulation, the total device area was 100 cm2, dielectric constant 13.1, band gap 1.35eV, intrinsic constant is 1×1010 cm-3, doping concentration is 1×1017 cm-3, electron number and hole number 1000 and 170 respectively, and the refractive index was 3.58. The optimized temperature and bulk recombination were 25°C and 1000μs respectively along with the efficiency of 18.258 % for both n and p - InGaN solar cell. Several graphs were plotted under the following conditions: a) bulk recombination time of p-InGaN and temperature are kept constant at 1000 μs and 25°C, the variation of bulk recombination time of n - type InGaN solar cell with base current and voltage, maximum current and voltage, and efficiency and maximum power were studied. b) bulk recombination time of n-InGaN and temperature are kept constant at 1000 μs and 25°C, the variation of bulk recombination time of p - type InGaN solar cell with base current and voltage, maximum current and voltage, and efficiency and maximum power were studied.

The sol-gel spin coating method was used for the preparation of the Zinc Oxide which was coated over polymer, transparent, and glass translucent substrates and characterized with the help of a UV-Vis Spectroscope. The wavelength bandgap of those samples was found to be 296nm, 310.5nm, and 330nm respectively. The actual band gap of ZnO is 388nm. Similarly, their optical bandgap energy calculated by the Tauc Plot method were 3.641eV, 3.385eV, and 3.495 eV respectively. The transparent polymer slide has the lowest wavelength bandgap and the translucent glass slide has the highest. Further, the bandgap’s value differs from its actual value to the difference in the absorption process due to the presence of the substrate. These results suggest that the choice of substrate can significantly impact the optical properties and performance of the zinc oxide thin film. This result can be applied in developing and optimizing zinc oxide thin films for various purposes, such as in solar cells, sensors, and optoelectronics. By carefully selecting the substrate, it may be possible to tailor the bandgap energy and other optical properties of the thin film to better suit the specific application.

Copper zinc tin sulfide solar cell (CZTS), Cu2ZnSnS4-based solar cells have shown promising conversion efficiency because of their ease of variation in configurations. In this work, the architecture of a ZnO–Al/i–ZnO/n–CdS/CZTS/Mo solar cell was optimized by using Silvaco Atlas simulation software. In this simulation study, the thickness and defect density of the CZTS layer has been varied to achieve the highest efficiency of 26.58

Abstract Patients with B-lymphoid malignancies have been consistently identified as a population at high risk of severe COVID-19. Whether this is exclusively due to cancer-related deficits in humoral and cellular immunity, or whether risk of severe COVID-19 is increased by anticancer therapy, is uncertain. Using data derived from the COVID-19 and Cancer Consortium (CCC19), we show that patients treated for B-lymphoid malignancies have an increased risk of severe COVID-19 compared with control populations of patients with non–B-lymphoid malignancies. Among patients with B-lymphoid malignancies, those who received anticancer therapy within 12 months of COVID-19 diagnosis experienced increased COVID-19 severity compared with patients with non–recently treated B-lymphoid malignancies, after adjustment for cancer status and several other prognostic factors. Our findings suggest that patients recently treated for a B-lymphoid malignancy are at uniquely high risk for severe COVID-19. Significance: Our study suggests that recent therapy for a B-lymphoid malignancy is an independent risk factor for COVID-19 severity. These findings provide rationale to develop mitigation strategies targeted at the uniquely high-risk population of patients with recently treated B-lymphoid malignancies. This article is highlighted in the In This Issue feature, p. 171

The impact of doping concentration and thickness of n-InGaN and p-InGaN regions on the power conversion efficiency of single junction-based InGaN solar cells was studied by the Silvaco ATLAS simulation software. The doping concentration 5 × 1019 cm−3 and 1 × 1015 cm−3 were optimized for n-InGaN and p-InGaN regions, respectively. The thickness of 300 nm was optimized for both n-InGaN and p-InGaN regions. The highest efficiency of 22.17% with Jsc = 37.68 mA/cm2, Voc = 0.729 V, and FF = 80.61% was achieved at optimized values of doping concentration and thickness of n-InGaN and p-InGaN regions of InGaN solar cells. The simulation study shows the relevance of the Silvaco ATLAS simulation tool, as well as the optimization of doping concentration and thickness of n- and p-InGaN regions for solar cells, which would make the development of high-performance InGaN solar cells low-cost and efficient.

This paper reports on the computational study to investigate the high-performance gallium arsenide (GaAs) solar cells based on the Al2O3 antireflection coating (ARC) layer by optimizing the carrier lifetime, doping concentration, energy bandgap, thickness of window and absorber layers. In this simulation, the parameters like GaAs as an absorber layer, CdS as a window layer, and fixed thickness of the Al2O3 ARC layer were selected for performing the personal computer one dimensional (PC1D) simulation. As compared to GaAs solar cell with no ARC layer, GaAs solar cell with Al2O3 ARC layer (90 nm) presented the high power conversion efficiency (PCE) of 24.60% at absorber thickness 6 mu m and 30 nm for window layer. The optimized values of carrier lifetime and doping concentration for high PCE were found to be 100 mu s and 1 x 10(17) cm(-3) for both absorber and window layers, respectively. The V-oc, PCE, and fill factor (FF) values gradually increased with the increase of carrier lifetime and doping concentration of the CdS window layer. At optimized parameters, the highest value of I-sc = 3.11 A, V-oc = 0.884 V and PCE = 24.60% were achieved by GaAs solar cells with Al2O3 ARC layer. This study proves that optimization of CdS window layer through carrier lifetime, thickness, doping concentrations, and bandgap, etc. would make the crucial component to manufacture cost-effective, high-performance GaAs solar cells based on Al2O3 ARC layer.

This work describes the thickness optimization of graphene oxide (GO) as an antireflection coating (ARC) layer using a low-cost deposition process and validates the experimental results by a simulation study. The optimization of GO thickness was carried out by varying the speed of the spin coating and characterized by various characterization tools. It was found that GO ARC of thickness 80 nm was optimized having the lowest average reflectance of ~7.69% which was lowered to other GO thicknesses. In a simulation study, the different GO thicknesses were selected as input parameters to explore the highest photovoltaic performances of Si solar cells. The Si solar cell with the GO thickness of 80 nm expressed the highest short-circuit current (Isc = 3.42 A), opencircuit voltage (Voc = 0.653 V), power conversion efficiency (18.78%), and FF (83.74%). The photovoltaic (PV) parameters such as Isc, Voc, FF, efficiency, and sheet resistance were characterized by varying the thickness of ARC layer at the junction depth range from 0.1 mu m to 0.5 mu m for Si solar cells. It was been found that the optimized thickness (80 nm) of the GO ARC layer exhibited high performance, photocurrent, external quantum efficiency (EQE) of 95%, and high generation of charge carriers. This simulation on optimizing the GO thickness for Si solar cells would provide the utilization of low-cost GO ARC for the development of high-performance Si solar cells.

Anti-reflective coating (ARC) layers on silicon (Si) solar cells usually play a vital role in the amount of light absorbed into the cell and protect the device from environmental degradation. This paper reports on the thickness optimization of hafnium oxide (HfO2) as an ARC layer for high-performance Si solar cells with PC1D simulation analysis. The deposition of the HfO2 ARC layer on Si cells was carried out with a low-cost sol-gel process followed by spin coating. The thickness of the ARC layer was controlled by varying the spinning speed. The HfO2 ARC with a thickness of 70 nm possessed the lowest average reflectance of 6.33% by covering wavelengths ranging from 400–1000 nm. The different thicknesses of HfO2 ARC layers were used as input parameters in a simulation study to explore the photovoltaic characteristics of Si solar cells. The simulation findings showed that, at 70 nm thickness, Si solar cells had an exceptional external quantum efficiency (EQE) of 98% and a maximum power conversion efficiency (PCE) of 21.15%. The thicknesses of HfO2 ARC considerably impacted the photovoltaic (PV) characteristics of Si solar cells, leading to achieving high-performance solar cells.

This paper reports the optimization of zinc selenide as a window layer for GaAs solar cells in terms of thickness, carrier concentration, and bandgap of the material. Zinc selenide has been chosen for the window layer for appropriate front surface combination with absorber layer for the best performance in GaAs solar cell. The characteristics like current-power curve and efficiency have been analyzed by the PC1D modeling tool by varying different parameters like thickness, carrier concentration, and bandgap of window layer. The short-circuit current of 3.2 A, open-circuit voltage of 0.871 V, and the highest power conversion efficiency of 24.55% of solar cell has been observed at the thickness of 50 nm of the window layer. The electron and hole densities have been observed 1.1 × 1016 cm−3 and 1 × 1015 cm−3 respectively at distance from front in the range from 0 μm to 5 μm. The highest power conversion efficiency of 24.26% has been achieved at carrier concentration 1 × 1016 cm−3, which confirms that the proposed GaAs solar cell could be highly efficient to fabricate commercially at low a cost.

MXenes are 2D ceramic materials, especially carbides, nitrides, and carbonitrides derived from their parent ‘MAX’ phases by the etching out of ‘A’ and are famous due to their conducting, hydrophilic, biocompatible, and tunable properties. However, they are hardly stable in the outer environment, have low biodegradability, and have difficulty in drug release, etc., which are overcome by MXene/Polymer nanocomposites. The MXenes terminations on MXene transferred to the polymer after composite formation makes it more functional. With this, there is an increment in photothermal conversion efficiency for cancer therapy, higher antibacterial activity, biosensors, selectivity, bone regeneration, etc. The hydrophilic surfaces become conducting in the metallic range after the composite formation. MXenes can effectively be mixed with other materials like ceramics, metals, and polymers in the form of nanocomposites to get improved properties suitable for advanced applications. In this paper, we review different properties like electrical and mechanical, including capacitances, dielectric losses, etc., of nanocomposites more than those like Ti3C2Tx/polymer, Ti3C2/UHMWPE, MXene/PVA-KOH, Ti3C2Tx/PVA, etc. along with their applications mainly in energy storing and biomedical fields. Further, we have tried to enlist the MXene-based nanocomposites and compare them with conducting polymers and other nanocomposites. The performance under the NIR absorption seems more effective. The MXene-based nanocomposites are more significant in most cases than other nanocomposites for the antimicrobial agent, anticancer activity, drug delivery, bio-imaging, biosensors, micro-supercapacitors, etc. The limitations of the nanocomposites, along with possible solutions, are mentioned.

Tremendous works have been devoted on reducing the materials costs and searching a low-cost antireflection (AR) layer in silicon (Si) solar cells. This work reports on the surface architectural of Si wafer (p-type) by growing the nanowires (NWs)-like structures through cost-effective wet-controlled etching method. The nanostructures over Si wafer were optimized in terms of sizes, lengths and densities by changing the etching conditions and thoroughly examined their growth and optoelectrical properties. The well-defined grown NWs textured on Si wafer exhibited the low average reflectance of ~ 2.25% in the full visible-NIR spectrum from 400 to 1000 nm which was well matched to the simulated average reflectance of 2.23%. A model was designed using PC1D simulation to evaluate the photovoltaic (PV) parameters of NWs textured Si wafer-based solar cells without AR layer. In this simulation, the length of SiNWs and reflectance were selected as input parameters to instigate the power conversion and quantum efficiencies of solar cells. The highest conversion efficiency of ~ 16.2% is observed when the average length of SiNWs and reflectance were ~ 2.52 μm and ~ 2.25%, respectively. Experimentally, the fabricated SiNWs-based solar cell with etching time of 20 min attained the highest conversion efficiency of 15.9% and the value was very close to simulated results. PV parameters of SiNWs-based solar cells without AR layer were comparable to commercial c-Si solar cells with SiNx AR layer. Thus, the controlled wet etching is an easy, facile method for fabrication of nanowires on Si wafer with low reflectance. The enhancement in optical and electrical properties would be expected to a great prospect in developing low-cost c-Si solar cells without AR layer.

This paper numerically explores the possibility of ultrathin layering and high efficiency of graphene as a back surface field (BSF) based on a CdTe solar cell by Personal computer one-dimensional (PC1D) simulation. CdTe solar cells have been characterized and studied by varying the carrier lifetime, doping concentration, thickness, and bandgap of the graphene layer. With simulation results, the highest short-circuit current (Isc = 2.09 A), power conversion efficiency (η = 15%), and quantum efficiency (QE~85%) were achieved at a carrier lifetime of 1 × 103 μs and a doping concentration of 1 × 1017 cm−3 of graphene as a BSF layer-based CdTe solar cell. The thickness of the graphene BSF layer (1 μm) was proven the ultrathin, optimal, and obtainable for the fabrication of high-performance CdTe solar cells, confirming the suitability of graphene material as a BSF. This simulation confirmed that a CdTe solar cell with the proposed graphene as the BSF layer might be highly efficient with optimized parameters for fabrication.

BACKGROUND:Hospitalized patients with COVID-19 have increased risks of venous (VTE) and arterial thromboembolism (ATE). Active cancer diagnosis and treatment are well-known risk factors; however, a risk assessment model (RAM) for VTE in patients with both cancer and COVID-19 is lacking. OBJECTIVES:To assess the incidence of and risk factors for thrombosis in hospitalized patients with cancer and COVID-19. METHODS:Among patients with cancer in the COVID-19 and Cancer Consortium registry (CCC19) cohort study, we assessed the incidence of VTE and ATE within 90 days of COVID-19-associated hospitalization. A multivariable logistic regression model specifically for VTE was built using a priori determined clinical risk factors. A simplified RAM was derived and internally validated using bootstrap. RESULTS:From March 17, 2020 to November 30, 2020, 2804 hospitalized patients were analyzed. The incidence of VTE and ATE was 7.6% and 3.9%, respectively. The incidence of VTE, but not ATE, was higher in patients receiving recent anti-cancer therapy. A simplified RAM for VTE was derived and named CoVID-TE (Cancer subtype high to very-high risk by original Khorana score +1, VTE history +2, ICU admission +2, D-dimer elevation +1, recent systemic anti-cancer Therapy +1, and non-Hispanic Ethnicity +1). The RAM stratified patients into two cohorts (low-risk, 0-2 points, n = 1423 vs. high-risk, 3+ points, n = 1034) where VTE occurred in 4.1% low-risk and 11.3% high-risk patients (c statistic 0.67, 95% confidence interval 0.63-0.71). The RAM performed similarly well in subgroups of patients not on anticoagulant prior to admission and moderately ill patients not requiring direct ICU admission. CONCLUSIONS:Hospitalized patients with cancer and COVID-19 have elevated thrombotic risks. The CoVID-TE RAM for VTE prediction may help real-time data-driven decisions in this vulnerable population.

This paper describes the simulation study for the optimization of high-performance cadmium telluride (CdTe) solar cells using different doping concentrations, carrier lifetimes, temperature, and thickness of layers of CdTe absorber and CdS window layers. In this simulation, the highest efficiencies of similar to 18% and similar to 18.29% achieved when the doping concentrations were 1.5 x 10(17) cm(-3) for absorber layer and 1 x 10(15) cm(-3) for window layer, respectively. The efficiency of the solar cell increases with increase in carrier lifetime and the highest efficiency of 18.26% achieved at carrier lifetime 100 mu s with doping concentration of 1 x 1017 cm(-3). Solar cell with the thickness of absorber layer 8 mu m at carrier lifetime 100 mu s attained the maximum efficiency of 19.18% whereas the efficiency of 18.33% was noticed in thickness of window layer 70 nm at 100 mu s carrier lifetime. The optimum efficiency of 18.3% with short-circuit current 2.66 A and open-circuit voltage 0.79 V of solar cell has been achieved at operating temperature 25 degrees C. The optimized energy band gap of absorber (1.7 eV) accomplished the highest efficiency of 18.31%. The photogeneration rate increases logarithmically as distance from front increases, while the recombination rate increases linearly, which could be suitable for fabrication of efficient solar cell.

Cadmium telluride (CdTe) is currently known to be one of the reliable cost-effective materials for manufacturing solar cells. In this work, different materials such as magnesium fluoride (MgF2), aluminum trioxide (Al2O3), tin oxide (SnO2), and magnesium oxide (MgO) were applied as a single antireflection coating (ARC) layer and characterized their optoelectrical properties of the resulting CdTe solar cells. A personal computer one-dimensional (PC1D) simulation study was carried out to instigate the overall performance when varying the thickness of the absorber and window layers. Simulation results confirmed that Al2O3 single ARC layer with thickness of 83 nm achieved the best efficiency of 17.81% as compared with the other ARC materials. The Al2O3 single ARC layer resulted in a short-circuit current of 2.89 A and open-circuit voltage of 0.740 V.

M′2M″xXyene (M′ and M″ are the early transitional metals and X is carbide with x = 1 for y = 2 and x = 2 for y = 3) are the ordered double transitional metal layered carbides derived from their parent MAX phases M′2M″xAlXyene by a wet chemical etching method. Their oxides are predicted to have topological properties for which they should be annealed at around 800 °C in an oxygen background. This paper includes the new ablated plasma thrust method for the ionization and adsorption of oxygen on the M′2M″xXyene substrate in the pulsed laser deposition chamber. We have found that the background pressure has a negative effect and the substrate temperature has a positive effect on plume expansion. The density profile of the background gas is highly affected by deposition temperature. Similarly, it is found that the density of plasma generated by longer wavelengths is not affected significantly due to the inverse bremsstrahlung process. A shorter wavelength produces the bremsstrahlung process as photoionization takes place. At a certain time (200 ns), the pressure of background gas and plasma pressure are equal (snow-plogh effect) so that all the wavelengths then produce electrons (highest for shorter wavelengths), thereby increasing its density. The energy necessary for the oxidation of the substrate is provided by the energy of the ablated species. The adsorption is assured by the reflective high electron energy diffraction technique, and it is found that the ambient gas pressures p = 0.1 mbar and 0.2 mbar are appropriate for the adsorption process. The obtained M′2M″xXyene oxides can be used for their topological test.