Dual modification engineering enabled efficient perovskite solar cells with high open-voltage of 1.233 V

Abstract

Interface engineering take as a crucial role in enhancing the performance of perovskite solar cells (PSCs). Here, we propose a comprehensive strategy to improve the performance and stability of PSCs through dual-interface modification approach. This strategy involves simultaneously introducing lead-free Cs3MnBr5: Ce3+ nanocrystals (NCs) between SnO2 electron transport layer and the perovskite layer, as well as 1H,1H-Perfluorooctylamine iodide (PFOAI) at the interface between perovskite and Spiro-OMeTAD hole transport layer. Firstly, we successfully prepare Cs3MnBr5: Ce3+ NCs, which exhibits an extensive ultraviolet response and effective blue photoluminescence. The photoluminescence quantum yield of Cs3MnBr5: Ce3+ NCs can reach 90 %, demonstrating efficient photon down-conversion ability and efficient defect passivation. Simultaneously, the organic halide salt PFOAI with super-hydrophobic properties efficiently passivates defects on the surface of perovskite and improves moisture-resistance of perovskite films. Taking advantage of these synergistic effects, we achieve efficient PSCs based the Cs0.05(FA0.83MA0.17)0.95Pb(I0.83Br0.17)3 and Cs0.05(FA0.95MA0.05)0.95Pb(I0.95Br0.05)3 with power conversion efficiency (PCE) of 23.88 % and 24.24 %. We also achieved an ultrahigh open-circuit voltage (VOC) of 1.233 V, which represents one of the highest VOC values in a perovskite film with a bandgap of ∼1.60 eV. Additionally, the non-encapsulated double-interface modified PSCs exhibit long time, light and humidity stability. This study explores a novel and comprehensive strategy for manufacturing PSCs with high VOC, high PCE, and good stability.