Diffusion-enhanced efficiency of perovskite solar cells

This study proposes a novel approach to improve the performance of third-generation solar cells, particularly perovskite solar cells (PSCs), by employing zinc oxide (ZnO) nanoparticles (NPs). The ZnO NPs are dispersed on the upper surface of the device, acting as nanodiffusers. This reduces reflection and increases solar radiation absorption in the photovoltaic active layer, enhancing the light pathway within the device. To analyze the impact of ZnO nanodiffusers on solar cell performance, computer simulations using the finite element method (FEM) and experimental analysis were conducted. Green synthesis methods were employed to synthesize ZnO nanoparticles with an average size of 160 nm, which were subsequently characterized. Thin films of ZnO NPs were deposited on the transparent indium tin oxide (ITO) electrode using spin coating, and their optical response was evaluated. This study proposes methodologies for optical and electrical modeling of third-generation photovoltaic cells using ZnO NPs. Optical computational modeling results evidence that ZnO nanospheres with a diameter of 160 nm predominantly scatter solar radiation in the forward direction. The incorporation of ZnO NPs (160 nm in diameter) reduces device reflectance, resulting in efficient light coupling and increased absorbance in the active layer. The integrated effects of light trapping and anti-reflective properties enhance photocurrent generation, leading to an increase in short-circuit current density. Experimental verification with ZnO NP deposition on PSCs confirms a 23.5% enhancement in photovoltaic device efficiency, increasing from 10.6 to 13.1% in an 11.68 cm2 perovskite cell. The study presents the optical benefits of ZnO nanostructures, including anti-reflective effects and light scattering, when integrated into devices containing thin films as active material.