3-Chloroperoxybenzoic acid doping spiroOMeTAD for improving the performance of perovskite solar cells

The perovskite solar cells (PSCs) is one of the fastest growing photovoltaic technology. However, the further improvement of performance and stability is the bottleneck issue of its large-scale manufacturing. The controllable oxidation of spiroOMeTAD is significant for high-performance PSCs. Here, a low-cost and facile strategy by doping 3-Chloroperoxybenzoic acid (m-CPBA) into spiroOMeTAD is demonstrated. The addition of m-CPBA accelerates the oxidation of spiroOMeTAD, produces more carriers, improves the hole conductivity, and reduces defects and carrier non-radiative recombination. On the other hand, the modification of m-CPBA adjusts the HOMO of hole transport layer (HTL), makes more match the energy array between HTL and perovskite layer, and reduces energy loss at interface. Consequently, the m-CPBA optimized PSCs achieves a power conversion efficiency (PCE) of 23.34% with an outstanding fill factor (FF) over 84%, along with excellent environmental stability.