The Role of Silver Nanoparticles in the Hole Transport Layer in Organic Solar Cells Based on PBDB-T:ITIC

In this work, the fabrication and characterization of organic solar cells under the bulk heterojunction approach in a direct architecture, with gold nanoparticles (Ag-NPs) disseminated into the hole transport layer (HTL) based on PEDOT:PSS is carried out. The active layer is a blend of PBDB-T donor with the non-fullerene electron acceptor ITIC. Ag-NPs dispersed in deionized water are synthesized by laser ablation protocols using a pulsed Nd:YAG laser. Results show an open-circuit voltage (Voc) of 0.84 V, a short circuit current density (Jsc) of 15.5 mA/cm2, a fill factor (FF) of 0.49% and a power conversion efficiency (PCE) of 6.4% when 5% of Ag-NPs are incorporated into the PEDOT:PSS layer; for pristine PEDOT:PSS film, the photovoltaic parameters are Voc of 0.85 V, Jsc of 15.4 mA/cm2, FF of 0.45% and PCE of 5.9%; these results mean an 8.5% of PCE enhancement with the Ag-NPs incorporation. Ag-NPs are introduced into the pristine layer PEDOT:PSS to increase light absorption into the active layer through the localized surface plasmonic resonance effect.