Efficient Perovskite Solar Cells through Suppressed Nonradiative Charge Carrier Recombination by a Processing Additive

It has been reported that nonradiative charge carrier recombination in hybrid perovskite materials restricts the device performance of perovskite solar cells. In this study, we report efficient perovskite solar cells through suppressed nonradiative charge carrier recombination by a processing additive, aminopropanoic acid. It is found that aminopropanoic acid not only modulates the crystal growth processes but also minimizes the defects of CH3NH3PbI3 thin films. Moreover, the CH3NH3PbI3 thin films processed with the addition of aminopropanoic acid exhibit both enhanced photoluminescence and electroluminescence and elongated charge carrier lifetime, indicating that nonradiative charge carrier recombination within the CH3NH3PbI3 thin films is drastically suppressed. As a result, perovskite solar cells fabricated using the CH3NH3PbI3 thin films processed with the addition of aminopropanoic acid exhibit approximately 15% enhanced efficiency as compared with those made with pristine CH3NH3PbI3 thin films. All of these results demonstrate that our findings provide a facile way to improve the efficiency of perovskite solar cells.