Solution-Processed Polymeric Thin Film as the Transparent Electrode for Flexible Perovskite Solar Cells

In the past decade, perovskite solar cells (PSCs) were arising as a new generation of low-cost solar technology for renewable energy generation. More than 25% of power conversion efficiency (PCE) was reported from PSCs on the rigid indium tin oxide (ITO)/glass electrode. However, PSCs fabricated on flexible solution-processed transparent electrodes have still been a challenge to date. In this work, we report a solution-processed transparent polymeric thin film as the electrode for flexible solution-processed PSCs. The solution-processed polymeric thin film exhibits superior optical transparency and decent electrical conductivity. As compared with a PCE of 16.60% from PSCs on the ITO/glass substrate, PSCs on the solution-processed transparent polymeric electrode/glass substrate exhibit a PCE of 13.36% and PSCs on the solution-processed transparent polymeric thin-film/polyethylene terephthalate flexible substrate possess a PCE of 10.16%. Systematic studies demonstrate that poor electrical conductivity of the solution-processed transparent polymeric electrode and serious interfacial charge carrier recombination are responsible for low PCEs. Nevertheless, our results demonstrate that we provide a facile route to develop flexible PSCs by utilization of solution-processed polymeric thin films as the transparent electrodes.