A multifunctional piperidine-based modulator for printable mesoscopic perovskite solar cells

Printable mesoscopic perovskite solar cells (PSCs) have received extensive attention due to their convenient large-area fabrication and good stability. The further improvement of the power conversion efficiency (PCE) of such simplified PSC configuration is limited by the low open circuit voltage (V-OC). The high density of defects at grain boundaries of perovskites inside the mesoporous scaffold can cause severe nonradiative recombination, which have negative effects on V-OC. Additive engineering has demonstrated advantages in improving the perovskite crystallization inside the pores, passivating the defects of perovskite and enhancing the performance of printable mesoscopic PSCs. Herein, we introduce a multifunctional modulator 1-(2-Chloroethyl) piperidine hydrochloride (ClEP) as an additive into the perovskite precursor solution. Benefiting from the strong interaction between ClEP and perovskite, it can interact with non-coordinating ions and defect states to achieve multi-defect passivation. As a result, the V-OC of the printable mesoscopic PSC increases from 895.25 mV to 982.24 mV and the ClEP-treated printable mesoscopic PSC reaches a champion PCE of 17.08%. This work provides a new approach for developing efficient printable mesoscopic PSCs.

Automated summary

Printable mesoscopic perovskite solar cells have gained attention for their large-area fabrication and stability. The power conversion efficiency is limited by low open circuit voltage. This study introduces a multifunctional modulator, ClEP, as an additive to improve the performance of these solar cells.