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

Perovskite solar cells (PSCs) utilizing self-assembled monolayers (SAMs) as hole transport layers (HTLs) have been successful. However, the integrity of SAMs is frequently compromised by organic solvent-induced erosion during subsequent deposition of perovskite films. To overcome this critical stability issue without increasing fabrication complexity, we propose a novel strategy in which SAM molecules are directly doped into the perovskite precursor solution. The in situ doping approach effectively compensates for solvent erosion, thereby enhancing the SAM coverage, improving the perovskite crystallinity, and significantly reducing the trap density at the buried interface. Consequently, the optimized devices exhibit superior film quality and a more robust HTL/perovskite interface, yielding a power conversion efficiency (PCE) of 25.16% and enhanced thermal and light stability. This straightforward approach offers a promising pathway for the development of low-cost, high-performance photovoltaic technologies.