Abstract
Organic small molecular materials with coplanar π-conjugated system as HTMs in perovskite solar cells (PSCs) have attracted considerable attention due to their high charge transport capability and thermal stability. Herein, three novel pentafulvalene-fused derivatives with or without fluorine atoms incorporated (YSH-oF and YSH-mF and YSH-H, respectively) are designed, synthesized, and applied as hole-transporting materials (HTMs) in PSCs fabrication. The fluorinated HTMs, YSH-oF and YSH-mF, exhibited higher hole mobility and better charge extraction at the perovskite/HTM interface than non-fluorinated one do, presumably due to the closer intermolecular π–π packing interactions. As a result, small-area (0.09 cm2) PSCs made with YSH-oF and YSH-mF achieved an impressive power conversion efficiency (PCE) of 23.59% and 22.76% respectively, with negligible hysteresis, in contrast with the 20.57% for the YSH-H-based devices. Furthermore, for large-area (1.00 cm2) devices, the PSCs employing YSH-oF exhibited a PCE of 21.92%. Moreover, excellent long-term device stability is demonstrated for PSCs with F-substituted HTMs (YSH-oF and YSH-mF), presumably due to the higher hydrophobicity. This study shows the great potential of fluorinated pentafulvalene-fused materials as low-cost HTM for efficient and stable PSCs.
Original language | English |
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Article number | 2306367 |
Journal | Advanced Functional Materials |
Volume | 33 |
Issue number | 48 |
DOIs | |
State | Published - 23 Nov 2023 |
Keywords
- fluorine-substituted small molecules
- hole-transporting materials
- long-term stability
- pentafulvalene-fused derivatives
- perovskite solar cells