Polydispersed Metal Nanoparticles at the Interface for Improved Optoelectronic Properties in Perovskite Photovoltaics

Enhancing the light photons which are responsible for the generation of the exciton in the photoactive layer is one of the primary ways to increase the net power conversion efficiency of solar cell. Using plasmonic metal nanoparticle is one of the well-known method to improve the solar cell performance. In this work, poly-dispersed aluminium nanoparticles (AlNPs) were embedded at the PC61BM/Al interface to investigate the effect of it on solar cell performance. It is observed that device with AlNPs at the PC61BM/Al interface showed significant enhancement in optical absorption and as a result improved JSC. It is observed that Al nanoparticles at cathode interface aids in light trapping and also reduction in series resistance. These coupled effects of optical and electrical enhancement tend to improve power conversion efficiency in the device. From this study, it is noted that addition of AlNPs modifies deep trap state distribution in the active matrix. Further, this study shows that AlNPs incorporation with ETL improves the device power conversion efficiency (PCE) mainly through the optical enhancement.