Photocurrent Enhancement of Perovskite Solar Cells at the Absorption Edge by Electrode-Coupled Plasmons of Silver Nanocubes

Abstract

The power conversion efficiency of efficient solar cells would be further improved by enhancement of light absorption at the absorption edge region by plasmonic nanoparticles. Here, we achieved this for perovskite solar cells (PVSCs) by taking advantage of electrode-coupled plasmons. We developed planar PVSCs with plasmonic silver nanocubes coupled electromagnetically with a silver back electrode. The plasmonic peak wavelength is adjusted to the absorption edge of the perovskite active layer (600–800 nm) by tuning the thickness of an electron-transport layer inserted in between the nanocubes and the electrode. The far-field scattering and optical near field from the nanocube face closest to the perovskite layer are also enhanced extensively by the coupling. The electrode-coupled plasmons enhance the photocurrents at the absorption edge. The average power conversion efficiency is also enhanced from 11.9% to 13.3%. The enhancement effect is more prominent for a thinner perovskite layer.