Design of Graphene-Coated Silver Nanoparticle Based on Numerical Solution to Enhance the Absorption of the Thin-Film Solar Cell

In this study, we designed a graphene-coated silver nanoparticle (GCSNP) for this purpose. We modeled its permittivity using the Kubo formula and an equivalent dielectric permittivity model. Our nanoparticle size was deliberately chosen to be significantly smaller than the resonance wavelength, allowing it to be treated as an isotropic homogeneous particle. The inherent plasmonic properties of nanoparticles can enhance the efficiency of photovoltaic cells by increasing their scattering cross-section. We computed the scattering cross-section of GCSNP through numerical solutions and optical simulations for graphene thicknesses ranging between 0.34 and 1 nm. Based on the scattering peak, we optimized the graphene coating thickness to be 0.8 nm. Subsequently, we embedded GCSNPs, each with a graphene thickness of 0.8 nm, within the absorber layer of a Si-based thin-film solar cell and analyzed its properties using the FDTD method. Compared to a similar cell designed with silver nanoparticles, our cell exhibited a 20.6% increase in absorption and a 7.3% rise in short-circuit current density. Finally, we investigated the impact of the geometry and dimensions of GCSNPs on the performance of Si-based thin-film solar cells, determining that a cylindrical shape with a diameter and height of 50 nm each serves as the optimized GCSNP.
Source: Plasmonics - Category: Biomedical Science Source Type: research