Enhanced Absorption for Solar Cell Applications in Lead Free CsSnI3 Perovskite by Embedding Plasmonic Nano-Octahedra

In this study, we have optimized the optical performance of a thin layer of lead free CsSnI3 photoactive layer for employment in plasmonics-enhanced solar cells, by embedding plasmonic gold octahedra in the CsSnI3 layer. Finite Difference Time Domain (FDTD) modelling is employed to analyse the absorption spectra, short circuit current density (Jsc) and carrier generation rate. The excitation of localized surface plasmon resonance (LSPR) due to the presence of gold nanooctahedra enhances the absorption in the layer in the wavelength range of 400nm to 1000nm. The Jsc of the 400 nm active layer with nano-octahedra is enhanced by 10.6 % i,e. 26.13 mA/cm2 as compared to a bare 400 nm active layer and is also highest reported for 400nm CsSnI3 layer. The maximum carrier generation rate for the active layer with nanooctahedra is 6.21 × 1029 1/m3/s. This enhancement in absorption of nanothin CsSnI3 layer demonstrates the potential of plasmonic nanoparticles in optimizing next-generation solar cells. This work paves path for the development of high efficiency lead free CsSnI3 perovskites solar cells which shall contribute to overall development of a sustainable energy ecosystem.