Multi‐Site Intermolecular Interaction for In Situ Formation of Vertically Orientated 2D Passivation Layer in Highly Efficient Perovskite Solar Cells

Abstract

Surface passivation via 2D perovskite is critical for perovskite solar cells (PSCs) to achieve remarkable performances, in which the applied spacer cations play an important role on structural templating. However, the random orientation of 2D perovskite always hinder the carrier transport. Herein, multiple nitrogen sites containing organic spacer molecule (1H‐Pyrazole‐1‐carboxamidine hydrochloride, PAH) is introduced to form 2D passivation layer on the surface of formamidinium based (FAPbI3) perovskite. Deriving from the interactions between PAH and PbI2, the defects of FAPbI3 perovskite are effectively passivated. Interestingly, due to the multiple‐site interactions, the 2D nanosheets are found to grow perpendicularly to the substrate for promotion of charge transfer. Therefore, an impressive power conversion efficiency of 24.6% and outstanding long‐term stability are achieved for the 2D/3D perovskite devices. The findings further provide a perspective in structure design of novel organic halide salts for the fabrication of efficient and stable PSCs.

Improvement of Photovoltaic Performance of Perovskite Solar Cells by Synergistic Modulation of SnO2 and Perovskite via Interfacial Modification

“…The introduction of CBTBC resulted in a significant enhancement of V OC and the fill factor (FF). This is because the intermolecular force between SnO 2 and CBTBC has been enhanced, which inhibits charge accumulation and recombination . Additionally, the buried interface of the perovskite has been optimized by CBTBC, which inhibits the density of trapping states at the interface.…”

High‐Quality Hybrid Perovskite Thin Films by Post‐Treatment Technologies in Photovoltaic Applications

“…In contrast, the energy gap of identical perovskite became narrow upon postprocessing by FA + . [71] Moreover, the introduction of wide-bandgap (E g ) materials, [72] in situ growth of 2D perovskite capping layers, [73][74][75][76][77] and the use of interlayers with strong electric dipole moment [42,69,[78][79][80][81][82][83] at the postprocessing stage can also optimize the interfacial energy band structure and enhance V bi , thereby improving charge transport and collection in PSCs (Figure 3c).…”

“…However, there are still some problems in the TA-free post-treatment process, such as poor crystal quality and uncontrollable film uniformity, leading to relatively poor efficiencies. [ 99] Gradient TA FTO/TiO 2 -SnO 2 /FA 0.95 Cs 0.05 PbI 3 /Spiro-OMeTAD/Ag 1.13 25.40 80.5 23.11 2021 [ 100] Gradient TA ITO/SnO 2 /(FAPbI 3 ) 0.95 (MAPbBr 3 ) 0.05 /Spiro-OMeTAD/Au 1.18 24.34 82.53 23.70 2022 [ 101] TA [ 71] TA + CdI 2 treatment ITO/PTAA/RbCsFAMAPbI 3 /C 60 /BCP/Cu 1.20 23.5 77.7 21.9 2020 [ 103] TA + NMAI treatment FTO/SnO 2 /CsFAMA/Spiro-OMeTAD/Au 1.184 22.98 77.34 21.04 2020 [ 126] TA + ZnP treatment FTO/c-TiO 2 /m-TiO 2 /MAPbI 3 /Co(II)P-Co(III)P/Au 1.12 23.42 77.54 20.56 2020 [ 150] TA [ 115] TA + PyI treatment FTO/SnO 2 /FA 0.9 Cs 0.1 PbI 2.8 Br 0.2 /Spiro-OMeTAD/Au 1.1566 23.698 81.2 22.26 2021 [ 130] TA + CYCl treatment FTO/SnO 2 /FAPbI 3 /Spiro-OMeTAD/Ag 1.144 26.144 83.5 24.98 2021 [ 138] TA + EDA treatment FTO/PEDOT:PSS/Cs 0.025 FA 0.475 MA 0.5 Sn 0.5 Pb 0.5 I 3 /PCBM/C 60 /BCP/Ag 0.86 31.86 80 21.74 2021 [ 142] TA + CMAI treatment FTO/c-TiO 2 /m-TiO 2 /FAPbI 3 /Spiro-MeOTAD/Au 1.149 25.75 80.9 23.94 2022 [ 114] TA + OLAI treatment ITO/2PACz/Cs 0.03 (FA 0.90 MA 0.10 ) 0.97 PbI 3 /C 60 /BCP/Ag ∼1.20 ∼25 ∼82 24.3 2022 [ 118] TA + 2FEABr treatment ITO/PTAA/MAPbI 3 /PCBM/BCP/Ag 1.166 22.39 80.7 21.06 2022 [ 127] TA + 4-ABAI treatment FTO/SnO 2 /Cs 0.05 (FA 0.83 MA 0.17 ) 0.95 (PbI 0.83 Br 0.17 ) 3 /Spiro-OMeTAD/Au 1.20 24.57 78.55 23.16 2022 [ 128] TA + TP6 treatment FTO/TiO 2 /(FAPbI 3 ) 0.95 (MAPbBr 3 ) 0.05 /Spiro-OMeTAD/Au 1.09 25.12 81.76 22.41 2022 [ 129] TA [ 144] TA + PVA treatment ITO/SnO 2 /FAPbI 3 /Spiro-OMeTAD/Au 1.149 25.24 80.0 23.2 2022 [ 151] TA + QPSCl treatment ITO/SnO 2 /FAPbI 3 /QPSCl/Spiro-OMeTAD/Ag 1.17 25.16 82.45 24.27 2023 [ 42] TA + ThFA treatment ITO/SnO 2 /FAPbI 3 /Spiro-MeOTAD/Au 1.18 24.66 80.74 23.28 2023 [ 74] TA + TEACl treatment ITO/MeO-2PACz/FA 0.75 Cs 0.25 Pb(I 0.8 Br 0.2 ) 3 /C 60 /BCP/Cu 1.23 20.74 84.33 21.47 2023 [ 75] TA + PAH treatment ITO/SnO 2 /FAPbI 3 /Spiro-OMeTAD/MoO 3 /Ag 1.18 25.6 81.4 24.6 2023 [ 76] TA + 3AMP treatment ITO/NiO x /2PACz/FAPbI 3 /PCBM/BCP/Ag 1.15 24.8 82.8 23.62 2023 [ 119] TA + NaBH 3 CN treatment FTO/PEDOT:PSS/FA 0.7 MA 0.3 Pb 0.5 Sn 0.5 I 3 /C 60 /BCP/Ag 0.85 32.6 77.0 21.3 2023 [ 105] (Cont...…”

Molecularly Engineered Multifunctional Bridging Layer Derived from Dithiafulavene Capped Spiroxanthene for Stable and Efficient Perovskite Solar Cells

“…Several approaches to address defect passivation in PSCs have been discussed and reported, such as the use of organic ammonium salts, ionic liquids, self-assembled molecules, polymers, and fullerene derivatives. , In addition to that, molecules with specific functional groups such as amino, carboxyl, sulfonate, cyano, carbonyl, fluorine, thiophene, and pyridine have been used as passivating materials in PSCs due to their interaction tendency with uncoordinated Pb 2+ present on the surface of the perovskite layer. − These passivation agents are mostly insulators that passivate the traps, causing charge recombination and providing environmental stability to the PSCs. Being electrically insulating in nature, these passivation agents do not contribute toward the charge transfer across the interfacial layer and can result in high electrical resistance in the device.…”