Modeling and Optimization of Graphene/GaAs Structured Solar Cells Toward Improved Energy Efficiency

The rising global demand for energy, coupled with environmental concerns associated with fossil fuels, has intensified the need for the development of novel technologies based on renewable energy sources. This study focuses on the modeling and optimization of a graphene/gallium arsenide (GaAs) Schottky junction solar cell to enhance power-conversion efficiency (PCE). The proposed structure consists of graphene, GaAs, and silicon oxide layers, simulated using Silvaco software along with advanced physical models, including thermionic emission, Auger recombination, and drift–diffusion mechanisms. The effects of key parameters—such as GaAs substrate thickness, number of graphene layers, graphene work function, and nanograting structures—on critical performance metrics, including open-circuit voltage (Voc), short-circuit current density (Jsc), fill factor (FF), and PCE were systematically investigated. In addition, the overall stability of the photovoltaic (PV) system was evaluated to ensure consistent and reliable energy conversion performance under continuous illumination. The results indicate that the optimal GaAs substrate thickness is approximately ۴ µm, and increasing the number of graphene layers up to three improves the efficiency by about ۱.۱۹۶%. The implementation of rectangular nanogratings enhances light absorption, achieving a final efficiency of nearly ۲.۰۵%. Furthermore, employing graphene with a work function of ۴.۵۵ eV significantly improves Voc and FF, yielding the best overall performance balance. These findings highlight the pivotal role of precise nanostructure design and the optimal selection of optical and electrical material properties in advancing next-generation graphene-based solar cells.

کلیدواژه ها:

PV system ، stability ، Efficiency ، solar cell ، Graphene