Energy Reports (Nov 2022)
Efficiency improvement of half-tandem CIGS/perovskite solar cell by designing nano-prism nanostructure as the controllable light trapping
Abstract
Utilizing photonic nanostructures is a very efficient technique to capture light in broadband as well as a cheap and flexible method in photovoltaic devices. In this article, the finite element method (FEM) is applied to investigate the novel structures for perovskite solar cells (PSCs) aiming to find methods to enhance light absorption in the active layer. Initially, in order to boost energy harvesting, we propose a bilayer heterojunction such a way that the CIGS layer is incorporated underneath the perovskite (CH3NH3PbI3) layer in the PSC to absorb a wider spectral region of solar power. The optimized thickness for the CIGS layer is determined at 500 nm where the power conversion efficiency (PCE) is increased from 14.37% to 17.62%. Then, in an effort to further increase the light absorption, nano-prism light-trapping configuration is used at the perovskite-CIGS interface, and the performance of cells is investigated at different heights of these nanostructures. Eventually, the height of 60 nm is where the highest performance with the short-circuit current density (Jsc) of 27.2 mA/cm2, the open-circuit voltage (Voc) of 0.84 V, and the PCE of 19.29%, are obtained, showing almost 35% improvement in comparison with the reference sample. The proposed structure enables high-performance and more applicable PSCs in the future.
