Synergistic Self-Assembled Monolayers Reinforce Buried Interface Anchoring for High-Efficiency Tandem Perovskite...

Area of Science:

• Materials Science
• Renewable Energy
• Nanotechnology

Background:

• Carbazole-based self-assembled monolayers (SAMs) are standard hole transport layers (HTLs) in perovskite solar cells (PSCs).
• These SAMs suffer from aggregation and poor perovskite anchoring, limiting device performance.
• Interfacial engineering is crucial for efficient and stable PSCs.

Purpose of the Study:

• To develop a synergistic SAM (syn-SAM) strategy for improved hole transport layers in PSCs.
• To mitigate aggregation and enhance interfacial properties using a blended SAM approach.
• To improve the efficiency and stability of perovskite solar cells and perovskite/silicon tandem cells.

Main Methods:

• Developed a syn-SAM by blending a non-planar molecule (3,3-(4-amino-4H-1,2,4-triazole-3,5-diyl)-dibenzo acid, ABT) with Me-4PACz.
• Utilized π-π interactions and hydrogen bonding to create dense and uniform SAMs.
• Investigated the impact of syn-SAM on perovskite film strain, interfacial charge recombination, and device performance.

Main Results:

• Syn-SAM strategy effectively mitigated aggregation and improved SAM anchoring to the perovskite layer.
• Single-junction inverted PSCs achieved power conversion efficiencies (PCEs) of 25.75% and 22.76% for different bandgaps.
• Monolithic perovskite/silicon tandem solar cells demonstrated high PCEs of 31.56% and 26.57%.

Conclusions:

• The syn-SAM approach significantly enhances interfacial properties and device performance in PSCs.
• This strategy is compatible with various perovskite bandgaps and tandem architectures.
• The developed devices exhibit excellent long-term storage and thermal stability.