Resonant Silicon Nanoparticles for Enhanced Light Harvesting in Halide Perovskite Solar Cells

TL;DR

This paper demonstrates that incorporating resonant silicon nanoparticles into perovskite solar cells significantly enhances light absorption and device efficiency, achieving record performance metrics and offering a universal strategy for improved optoelectronic devices.

Contribution

The study introduces the use of low-loss, chemically inert silicon nanoparticles for light trapping in perovskite solar cells, surpassing previous metallic nanoparticle approaches.

Findings

Device efficiency increased up to 18.8%

Fill factor improved to 79%

Silicon nanoparticles enhance light absorption, not charge separation

Abstract

Implementation of resonant colloidal nanoparticles for improving performance of organometal halide perovskites solar cells is highly prospective approach, because it is compatible with the solution processing techniques used for any organic materials. Previously, resonant metallic nanoparticles have been incorporated into perovskite solar cells for better light absorption and charge separation. However, high inherent optical losses and high reactivity of noble metals with halides in perovskites are main limiting factors for this approach. In turn, low-loss and chemically inert resonant silicon nanoparticles allow for light trapping and enhancement at nanoscale, being suitable for thin film photovoltaics. Here photocurrent and fill-factor enhancements in meso-superstructured organometal halide perovskite solar cells, incorporating resonant silicon nanoparticles between mesoporous TiO2 transport and active layers, are demonstrated. This results in a boost of the device efficiency up to 18.8\% and fill factor up to 79\%, being a record among the previously reported values on nanoparticles incorporation into CH3NH3PbI3 (MAPbI3) perovskites based solar cells. Theoretical modeling and optical characterization reveal the significant role of Si nanoparticles for increased light absorption in the active layer rather than for better charge separation. The proposed strategy is universal and can be applied in perovskite solar cells with various compositions, as well as in other optoelectronic devices.