Interface modification to achieve high-efficiency and stable perovskite solar cells

The organic-inorganic hybrid perovskite solar cells (PSCs) achieve relatively high power conversion efficiencies (PCEs) over the past few years. However, defects on the surface and at the grain boundaries of the perovskite active layers are critical factors in ensuing perovskite devices. It is still a huge challenge to imminent the commercial use of this technology by passivating the defects of perovskite materials and corresponding interfaces. Here, we employ the HBPC ((4 & PRIME;-pentyl-[1,1 & PRIME;-biphenyl]-4-yl)methanaminium iodide) interface passivation strategy to prepare high-quality perovskite surfaces, which can significantly improve the efficiency and stability of PSCs. As compared to control cell (20.0%), the HBPC-passivated perovskite device achieves a champion PCE of 22.07% with less hysteresis. The obtained results show that the presence of HBPC on the perovskite film can reduce the charge trap density and extend the carrier recombination life, thereby boosting the performance of perovskite devices, leading a great promise in the pursuit of high-efficiency and stable PSCs.