An easy method to modify PEDOT:PSS/perovskite interfaces for solar cells with efficiency exceeding 15%

Herein, we show that surface treatment of PEDOT:PSS films using propionic acid (PA) results in better device performance for the resulting CH3NH3PbI3 perovskite solar cells (PCE > 15%). N-2 blow spreading of PA appears critical in enhanced performance. This weak acid treatment leads to no worse roughness, while providing larger perovskite grains.