LAUSR

There are two critical strategies to achieve the high photoelectric conversion efficiency of polymer photovoltaic cells: broadening the light absorption spectra of the active layer and efficiently splitting photogenerated excitons with a low probability of recombination. Herein, we demonstrate the improved light trapping and reduced photogenerated exciton recombination probability of the inverted heterojunction solar cells by incorporating C60 fullerene modification. This approach ameliorates traditional multiblend/layer systems, and allows multiple acceptor materials to synergistically work. After the fullerene modification layer was incorporated, the optimal device presents a 25.5% improvement of power conversion efficiency (PCE) up to 9.458% with an open circuit voltage (Voc) of 0.8 V, a short-circuit current (Jsc) of 18.575 mA/cm2, and a fill factor (FF) of 63.4%. This study provides a novel inspiration for the structure development of high-efficiency photovoltaic devices.