Copper zinc tin sulfide (CZTS) and copper zinc tin sulfo selenide (CZTSSe) kesterite minerals are nontoxic and abundant in the earth with the promise of cost-effective photovoltaic applications. This study explains a tandem solar cell made of kesterite materials that can capture sunlight over a broad spectrum. The proposed tandem structure comprises a wide bandgap CZTS thin-film upper subcell and an underlying narrow bandgap CZTSSe-based lower subcell. The upper and lower subcells are simulated using solar cell capacitance simulator-one dimension and validated against the experimental results to determine the viability of the proposed tandem design. Additionally, the performance of both subcells is evaluated for tandem configuration by adding a back surface field layer, a modification of the back contact, testing at different thicknesses, and doping of both subcell absorber layers. As a result, optimizing both subcells improved tandem solar cell open-circuit voltage (V _oc) to a maximum of 1.5 V, which led to an efficiency of 23.99% at the current matching condition. Furthermore, how light radiation power and temperature variations impact the proposed solar cell performance is being investigated. This study provides significant insights into efficient tandem solar cell design and manufacture.

This theoretical study looks into the mechanical and thermal behaviour of CH₃NH₃SnIxBr_3-x:PCBM. Large-scale Atomic/Molecular Massively Parallel Simulator (LAMMPS) and Packmol software and Molecular Dynamic Methods are applied for simulation and computation. The stress–strain profile, Young’s modulus, and the density of the lattice are studied by inserting a load in different directions. Poisson’s ratio for the PCBM doped CH₃NH₃SnIxBr_3-x was calculated via coding by Packmol software. In detail, a certain load was clamped onto the CH₃NH₃SnIxBr_3-x: PCBM lattice. Then the elongation was indicated in different directions (X, Y, Z), and the stress–strain curve and Young’s modulus were obtained. Lastly, the mechanical behaviour of CH₃NH₃SnIxBr_3-x: PCBM were studied basing on three different lattice orientations, and the assumption of bearing a specific tension at three different temperatures taken. The calculated Young’s modulus and Poisson’s ratio were very close to the experimental data previously reported, and this proved the high accuracy of this simulation work. This theoretical study therefore, profoundly addresses the current demands on extending the lifetime of perovskite and perovskite issuing devices. GRAPHICAL ABSTRACT

The performance of black silicon solar cells with various passivation films was characterized. Large area (156×156 mm²) black silicon was prepared by silver-nanoparticle-assisted etching on pyramidal silicon wafer. The conversion efficiency of black silicon solar cell without passivation is 13.8%. For the SiO₂andSiNx:H passivation, the conversion efficiency of black silicon solar cells increases to 16.1% and 16.5%, respectively. Compared to the single film of surface passivation of black silicon solar cells, the SiO₂/SiNx:H stacks exhibit the highest efficiency of 17.1%. The investigation of internal quantum efficiency (IQE) suggests that the SiO₂/SiNx:H stacks films decrease the Auger recombination through reducing the surface doping concentration and surface state density of the Si/SiO₂interface, andSiNx:H layer suppresses the Shockley-Read-Hall (SRH) recombination in the black silicon solar cell, which yields the best electrical performance of b-Si solar cells.

Organic–inorganic perovskites provide a favourable material system for photon and force-driven electronic systems. Lead-free methylammonium perovskite has the advantage, being an eco-friendly and simple material that can be used directly in smart and wearable electronic textile systems. However, its usage in wearables risks it being worn off and collapsing in a short time. This research assessed the resistance of lead-free methylammonium perovskite (CH₃NH₃SnI₃) to mechanical impacts by employing Large-scale Atomic/Molecular Massively Parallel Simulator molecular dynamics theories. To show the effect, stress–strain behaviour and Young’s moduli of CH₃NH₃SnI₃ were simulated by considering its molecular lattice. First, a two-axis (planar) model simulates stress and strain. Further computations were then performed to obtain the Poisson ratio, shear modulus, torsional modulus, and Pugh’s ratio. This simulation’s output renders a theoretical framework for the design and engineering of long-lasting wearable photon, and force-driven electronic and wearable devices based on CH₃NH₃SnI_3. GRAPHICAL ABSTRACT