Efficient and Stable Inverted Wide-Bandgap Perovskite Solar Cells and Modules Enabled by Hybrid Evaporation-Solution Method

Wide-bandgap perovskite solar cells (WBG-PSCs), when partnered with Si bottom cells in tandem configuration, can provide efficiencies up to 44%; yet, the development of stable, efficient, and scalable WBG-PSCs is required. Here, the utility of the hybrid evaporation-solution method (HESM) is investigated to meet these demanding requirements via its unique advantages including ease of control and reproducibility. A PbI₂/CsBr layer is co-evaporated followed by coating of organic-halide solutions in a green solvent. Bandgaps between 1.55–1.67 eV are systematically screened by varying CsBr and MABr content. Champion efficiencies of 21.06% and 20.35% in cells and 19.83% and 18.73% in mini-modules (16 cm²) for perovskites with 1.64 and 1.67 eV bandgaps are achieved, respectively. Additionally, 18.51%-efficient semi-transparent WBG-PSCs are implemented in 4T perovskite/bifacial silicon configuration, reaching a projected power output of 30.61 mW cm⁻² based on PD IEC TS 60904-1-2 (BiFi200) protocol. Despite similar bandgaps achieved by incorporating Br via MABr solution and/or CsBr evaporation, PSCs having a perovskite layer without MABr addition show significantly higher thermal and moisture stability. This study proves scalable, high-performance, and stable WBG-PSCs are enabled by HESM, hence their use in tandems and in emerging applications such as indoor photovoltaics are now within reach.     

Experimental and Simulation Investigation on Energy Absorption of Cu Casting Lattice Structure during Compression

This investigation aims to assess the mechanical behavior and energy absorption properties of the Cu lattice structures made by investment casting method experimentally and by finite element method (FEM) simulation. The casting pattern of lattice structures is additively manufactured with 2.0, 2.5, and 3.0 mm diameters and the lattice structures produced by investment casting of Cu. Then a uniaxial compression test is applied to measure maximum compressive strength, energy absorption density, efficiency, and specific energy absorption. The simulation and the experimental results indicate that the abovementioned properties of the lattice structures have a significant improvement and properties developments will rise by increasing the diameter of the struts. The mechanical characterization has done for Cu lattice structure with 3.0 mm strut diameter, which endures a stress of 242 MPa at the densification strain and the maximum tolerated stress of 404 MPa. The energy absorption density of this lattice structure is 67 MJ m⁻³ and has a specific energy absorption of 28 J g⁻¹ followed by an energy absorption efficiency around 70%. The simulation result shows a mathematical connection between the unit cells and the final lattice structures in terms of maximum tolerated stresses, which can help the prediction of the mechanical behavior of these structures.     

A Novel Nanoscale SOI MOSFET by Using a P-N Junction and an Electrically Hole Free Region to Improve the Electrical Characteristics

Silicon - In this paper, a SOI MOSFET is proposed using a P-N structure and an electrically hole-free region (EHFR-SOI). In this structure, to improve the electrical characteristics such as short...