Mixed-halide perovskites enable the creation of high-performance and low-cost solar cells. Chloride incorporation enhances film morphology, carrier diffusion length, and stability, improving device performance. Nevertheless, optimizing film thickness, defect density, and metal contact work function remains insufficiently explored, despite its potential to enhance power conversion efficiency. In this study, a numerical simulation was performed using SCAPS-1D (version 3.3.10) to identify the optimal parameters for the FTO/TiO₂/CH₃NH₃Pb_3−xCl_x/Spiro-OMeTAD/Au configuration. The best performance parameters that have been published in the literature based on experimental results are as follows: V_OC = 1.077 V, J_SC = 21.45 mA/cm², FF = 77.57%, and PCE = 17.97%. In contrast, the performance parameters obtained from numerical simulations for the same structure are V_OC = 1.28 V, J_SC = 21.63 mA/cm², FF = 78%, and PCE = 21.53%. In our numerical analysis, we achieved efficiencies that were comparable to those reported in experimental studies, and after optimization, superior performance parameters were attained, including V_OC = 1.179 V, J_SC = 27.26 mA/cm², FF = 81.03%, and PCE = 26.07%. These results indicate that optimized parameters can be integrated into the design and fabrication of mixed-halide perovskite solar cells to enhance performance.

Inverted perovskite solar cells (PSCs) have gained much attention due to their low hysteresis effect, easy fabrication, and good stability. In this research, an inverted perovskite solar cell ITO/PEDOT:PSS/CH₃NH₃PbI₃/PCBM/Ag structure was simulated and optimized using SCAPS-1D version 3.3.10 software. The influence on the device of parameters, including perovskite thickness, total defect density, series and shunt resistances, and operating temperature, are discussed and analyzed. With optimized parameters, the efficiency increased from 13.47% to 18.33%. Then, a new $\mathrm{Si}{\mathrm{O}}_{\mathrm{x}}$/ITO/PEDOT:PSS/CH₃NH₃PbI₃/PCBM/Ag device was proposed which includes a silicon-rich oxide ($\mathrm{Si}{\mathrm{O}}_{\mathrm{x}}$) layer. This material was used as the down-conversion energy material, which converts high-energy photons (ultraviolet UV light) into low-energy photons (visible light), improving the stability and absorption of the device. Finally, with $\mathrm{Si}{\mathrm{O}}_{\mathrm{x}}$, we obtained an efficiency of 22.46% in the simulation. Therefore, the device with the $\mathrm{Si}{\mathrm{O}}_{\mathrm{x}}$ layer is the most suitable as it has better values for current density–voltage output and quantum efficiency than the device without $\mathrm{Si}{\mathrm{O}}_{\mathrm{x}}$.

Tool selection is relevant because a wide variety of materials exhibit different machinability behaviors. Tool life during manufacturing is commonly associated with productivity. Insert developers have been using coatings on cutting tools to enhance their performance, with chemical vapor deposition (CVD) and physical vapor deposition (PVD) being the two most used techniques. This study analyzed the cutting tool wear mechanism by machining AISI D2 steel using two different inserts of TiAlN/TiN PVD and TiCN/Al₂O₃ CVD as layers deposited on a carbide substrate. The two inserts were tested at three different cutting speeds, namely, low, medium, and high; these values were below the data suggested by the supplier catalog. The flank wear and rake face were analyzed using scanning electron microscopy (SEM) and energy-dispersive X-ray spectrometry (EDX). The adhesion material, edge deformation, and abrasion were the main wear mechanisms before catastrophic damage occurred at the three different cutting speeds in the PVD cutting tool. Nevertheless, increasing the cutting speed reduced the tool life from 84% to 61% at high values compared to the medium values of PVD and CVD, respectively, where the medium value resulted in a balance between the material removal rate and tool life. The wear mechanism of the CVD tool was BUE and chipping; nevertheless, its craters were larger than those of the PVD. Compared to those configured for PVD, the CVD insert demonstrated the ability to machine D2 steel at twice the cutting speed with a workpiece surface roughness of 0.3 µm, in contrast to a variation of 0.6 to 0.15 µm with the PVD tool.

Gray cast iron (GCI) is a common material in the automotive industry due to its mechanical characteristics, which change primarily for materials employed for the foundry and cooling rate of material. According to the workpiece, the material of the cutting tool and cutting parameters are analyzed to improve the machining and to increment the lifetime of the tools. In this research, the foundry and machining process of an automotive component using ceramic and coated carbide tools were the study case, and the effect that they have on the age strengthening of GCI on the tool wear of the cutting tools was studied. Both inserts have the capability to machine the material with a rough surface between 1.5 to 2.0 μm. The wear mechanism of inserts and the microstructure of GCI were characterized with microscopy techniques, atomic force microscope (AFM), and energy dispersive X-ray spectroscopy (EDS). The microstructure of the workpiece shows a casting with flake graphite morphology that is linked with the induction of microcracks in the material. The experimental analysis shows that the GCI with 12 days of aging has an increased tensile strength. This improves the tool life of ceramic and coated carbide tools. There is a 50% reduction in flank wear with inserts that are machined with the GCI within five days of aging, compared with the material within twelve days. The rake face and flank wear show that abrasive and adhesive wear are the main mechanisms of ceramic inserts due to the high cutting speed. Meanwhile, adhesive and oxidative wear in the flank were the predominant type of wear for coated carbide tools.

Using a theory of homogenization that consists in the discretization of the inclusion of a binary phononic crystal in small volumes, in which the material parameters can be expanded in Fourier series, we have determined the dependence of the effective elastic parameters as a function of the frequency. In particular, the frequency dependence of all the elements that constitute the effective tensors of stiffness (moduli of elasticity) and density was analyzed for a 1D phononic crystal conformed of materials whose main characteristic is the high contrast between their elastic properties. In this dynamic case of homogenization, it was found that the effective parameters can reproduce the exact dispersion relations for the acoustic modes that propagate along the periodicity direction of the crystal. Particularly, in the second pass band (high-frequency branch) corresponding to the transverse vibrational modes, the homogenized elastic phononic crystal exhibits a metamaterial behavior because the effective C₄₄-component (shear modulus) and dynamic mass density were found to be both negative. It is noteworthy that the study derived from this homogenization technique can lead to design of double negative metamaterial systems for potential applications.

This research study conducts a computational analysis of a two-terminal (2T) Perovskite-on-silicon (PVK-Si) solar cell with a tandem configuration. The motivation for this analysis arises from the outstanding potential of PVK-Si solar cells to surpass the efficiency limitations of conventional photovoltaic technology. The tandem configuration utilizes a combination of CsSnBr₃ in the top sub-cell and crystalline silicon (c-Si) in the bottom sub-cell. After optimizing parameters of the top sub-cell (FTO/TiO₂/CsSnBr₃/rGO/Au), which included the thicknesses of CsSnBr₃ (500 nm), TiO₂ (40 nm), rGO (50 nm), the interface defects (10¹³ cm⁻²), and the bandgap of CsSnBr₃ (1.78 eV), the PVK-Si tandem device was simulated. As a result, the top CsSnBr₃ sub-cell achieved an efficiency of 21.62%, while the bottom silicon sub-cell achieved an efficiency of 23.48%. Subsequently, the sub-cells were interconnected in series using filtered spectra and current-density matching. After interpolating the J-V curves, the tandem exhibited a global efficiency of 29.76%, a fill factor (FF) of 85.30%, a matched current density (J_SC) of 19.02 mA/cm², and an open-circuit voltage (V_OC) of 1.83 V. The EQE results confirmed efficient photon management via complementary sub-cell absorption. The performance is competitive with experimental lead-based tandems and exceeds that of current lead-free simulations. Therefore, this research proposes a viable pathway for the development of non-toxic, cost-effective tandem solar systems with manufacturing capabilities.