Gold nanorods as performance enhancers in planar perovskite solar cells: A numerical study

Abstract

The quest for efficient and sustainable energy sources calls for an optimized optical design in photovoltaic technologies, particularly in perovskite solar cells (PSCs). This study focuses on the numerical analysis of integrating plasmonic non-spherical gold nanorods into realistic n-i-p MAPbI3 PSCs. The research addresses the light-harvesting enhancement, especially in near-infrared (NIR), a known limitation of metal halide PSCs. Nanorods were the selected nanostructures, as their longitudinal plasmon resonance has the potential to cover the NIR spectral limitation. The study aims to optimize the size, aspect ratio, orientation, and distance between nanorods, as well as provide insights into practical solutions for the positioning and encapsulation of the nanorods. The findings reveal that the aspect ratio and orientation of the nanorods significantly impact the absorption enhancement. Optimal outcomes are achieved with the vertical orientation of the nanorods, parallel to the stacking direction of the solar cell films. The most promising results from this study demonstrate that the incorporation of gold nanorods with small aspect ratios close to 1.5 leads to the potential enhancement of the perovskite photocurrent by at least 5 % (for spherical nanoparticles the maximum is 4.4 %). Additionally, it is also possible to reduce the layer thickness and the associated lead amount by at least 33 %, while maintaining the solar cell performance.