Enhanced stability of plasmonic polymer solar cells using ferrocenedicarboxylic acid modification

The power conversion efficiency (PCE) of polymer solar cells (PSCs) can obviously be improved by plasmon resonance effects of noble metal nanoparticles. However, incorporating noble metal such as Ag and Au nanoparticles (NPs) can usually accelerate the deterioration of PSCs due to the diffusion of noble metal atoms, which would limit the potential application of plasmonic PSCs. PSCs with ferrocenedicarboxylic acid (FDA) modified Al-doped ZnO (AZO) layer compared to pure AZO layer can synchronously increase PCEs and ultraviolet (UV) and moisture stabilities. PSCs with Ag NPs doped Al-doped ZnO (AZO:Ag) increased to 10.20% of PCE from 9.08% PCE of the reference PSCs with pure AZO layer, but show inferior stability. Furthermore, PSCs with FDA modified AZO:Ag layer obtained 10.0% of PCEs and showed superior UV durability and moisture stability. PSCs with FDA modified AZO:Ag layer respectively maintain the original PCE values of 50% and 53% exposing UV light for 13 h and aging for 9 months at RH 10%, which are obviously higher than 36% and 34% of the original PCEs of PSCs with AZO:Ag layer. The results indicate that FDA modification is an effective strategy to solve the quick deterioration of plasmonic PSCs without evidently sacrificing PCEs.