Alumina nanoparticles with different average particle sizes were synthesized by pulsed laser ablation of Al plates in ethanol, followed by laser irradiation at different times. Their optical and structural properties were investigated by different techniques. The experimental work showed that as the time of post-laser irradiation increased, the average particles’ size of alumina decreased. The decrease in the particle size is detected by using x-ray diffraction (XRD) technique and UV-visible absorption spectroscopy technique (UV–VIS) and characterized by laser-induced breakdown spectroscopy (LIBS). The LIBS technique was utilized as a diagnostic tool with XRD and UV–VIS for determining the nanoparticles’ size. Laser-induced plasma parameters such as electron density and electron temperature were determined. A relationship has been established between the electron temperature and the nanoparticles’ size. The results reflect the significance of correcting the spectral intensity of the emitted line for the effect of self-absorption in the LIBS experiment.

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 (J_sc) 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 J_sc 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.

Solar cells can be designed for indoor applications to provide a feasible solution for harnessing photon energy from indoor lighting. In this paper, we analyze the suitability of a selenium-based solar cell for gathering photon energy emitted by indoor light-emitting diodes (LEDs). The absorption band of selenium (Se) is found to be aligned with the LED spectrum, making it a promising contender for efficient indoor applications. In order to simulate the Se-based photovoltaic (PV) device, we started by calibrating the simulation model against a fabricated Se cell that was tested under AM1.5G. After the verification of the physical models and the technological key factors of the different layers incorporated in cell design, a systematic approach was performed to assess the operation of the Se solar cell under an LED light environment. We show an optimized power conversion efficiency (PCE) of 26.93% for the Se-based cell under LED illumination (311 μW/cm²). This is achieved by providing an effective design that incorporates a double-ETL structure, which can significantly improve the band alignment between the different layers of the cell device. The simulation results presented in this work serve to judge the potential of Se solar cells as indoor PVs and offer an approach for providing indoor use specifically designed for internet-of-things (IoT) devices.