Fully-ambient-air and antisolvent-free-processed stable perovskite solar cells with perovskite-based composites and interface engineering

For commercialization of perovskite solar cells (PSCs), the device stability issues attributed to degradation of perovskite material, photo and thermal instability, and photocurrent density-voltage (J-V) hysteresis behavior should be solved. Furthermore, most of presented high efficiency PSCs utilize an antisolvent-strategy to assist perovskite crystal growth with large grain-size and excellent coverage. To solve such issues, we developed fullyambient-air and antisolvent-free processes for the fabrication of PSCs with perovskite-based composites (i.e., MAPbI(3-x)Cl(x)-Cu:NiO, MAPbI(3-x)Cl(x)-Cu:NiO-carbon-graphite and MAPbI(3-x)Cl(x)-Al2O3). Such perovskite composites based cells with interface engineering yielded high power-conversion-efficiency (PCE) of 18.6% and fill factor (FF) of 78.3% with excellent reproducibility. More importantly, the target cells showed hysteresis-free behavior and dramatic enhancement in air-, photo- and thermal-stability. Compared to the pristine cells, the target device showed remarkable long-term stability with retaining almost 100% of the initial values of V-oc and J(sc) and similar to 94% of FF and PCE over 280 days.