Polymer Solar Cells Employing Water-Soluble Polypyrrole Nanoparticles as Dopants of PEDOT:PSS with Enhanced Efficiency and Stability

Water-soluble polypyrrole nanoparticles (PPy NPs) were developed and demonstrated as effective modifiers of PEDOT:PSS. By using them as the anode interfaces of polymer solar cells (PSCs), these PSCs showed a high power conversion efficiency (PCE) with the value of 9.48% as doping 20% PPy NPs into PEDOT:PSS. Interestingly, the enhancement of ∼16% and ∼150% compared with that of pure PEDOT:PSS (PCE = 8.04%) and PEDOT:PSS-free (PCE = 3.76%) was observed. Importantly, the stability of these devices with 20% PPy NPs doped PEDOT:PSS was also improved significantly. The enhanced performance was possible attributed to the changes of pH value, enhanced conductivities, and morphological changes of PEDOT:PSS. Our study supplies an alternative method to obtain high-efficient PSCs with the development of polymer NPs interfacial materials.