Mitigating Solvent Erosion to Enhance Self-Assembled Monolayer Coverage and Perovskite Solar Cell Performance.

Area of Science:

• Materials Science
• Renewable Energy
• Photovoltaics

Background:

• Self-assembled monolayers (SAMs) are used as hole transport layers (HTLs) in perovskite solar cells (PSCs).
• Organic solvents used in perovskite film deposition can erode SAMs, compromising device stability.
• Existing methods to protect SAMs often increase fabrication complexity.

Purpose of the Study:

• To develop a novel, simple strategy to enhance the stability of SAMs in PSCs.
• To improve the performance and durability of perovskite solar cells.
• To address the challenge of solvent-induced erosion of HTLs during PSC fabrication.

Main Methods:

• Doping SAM molecules directly into the perovskite precursor solution before film deposition.
• In situ doping to protect SAMs from solvent erosion during perovskite layer formation.
• Characterization of SAM coverage, perovskite crystallinity, and interface trap density.

Main Results:

• In situ doping effectively prevented SAM erosion, leading to enhanced SAM coverage.
• Improved perovskite crystallinity and significantly reduced trap density at the HTL/perovskite interface.
• Optimized devices achieved a power conversion efficiency (PCE) of 25.16% with enhanced thermal and light stability.

Conclusions:

• Directly doping SAMs into perovskite precursor solutions is a viable strategy to overcome stability issues.
• This approach enhances device performance and durability without adding fabrication complexity.
• The method offers a promising pathway for developing low-cost, high-performance perovskite solar cells.