Pre-buried Interface Strategy for Stable Inverted Perovskite Solar Cells Based on Ordered Nucleation Crystallization

The buried interface has important effect on carrier extraction and nonradiative recombination of perovksite solar cells (PSCs). Herein, to inactivate the buried interfacial defects of perovskite and boost the crystallization quality of perovskite film, 3-amino-1-adamantanol (AAD) serves as a pre-buried interface modifier on nickel oxide (NiOx) surface to regulate the nucleation and crystallization process of perovskite precursor. The amino and hydroxyl groups in AAD molecule can synchronously coordinate with nickel ion (Ni3+) in NiOx and lead ion in perovskite, respectively. The dual action favors the ordered arrangement of AAD molecules between NiOx and perovskite, which not only enhances hole extraction in hole transport layer, but also provides active sites for homogeneous nucleation. Furthermore, AAD modifier blocks the unfavorable reaction between Ni3+ and perovskite, and effectively passivates the buried interfacial defects. The optimal inverted PSCs achieve a champion power conversion efficiency of 22.21% with negligible hysteresis, favorable thermal, optical, and long-term stability. Thus, this strategy of modulating perovskite nucleation and crystallization by pre-buried modifier is feasible for achieving efficient and stable inverted perovskite solar cells.