Overview

• The Th-2EPT phenothiazine-based SAM replaces PEDOT:PSS to form high-quality tin perovskite films with improved optoelectronic properties.
• Density functional theory revealed that MeO-2PACz SAMs misalign with the perovskite lattice, prompting the search for a better-fitting interface molecule.
• Solar cells incorporating Th-2EPT achieved a record 8.2% efficiency, outperforming devices using PEDOT:PSS or MeO-2PACz contact layers.
• Valerio Stacchini confirms that performance gains stem from the superior optoelectronic quality of perovskite films grown on the novel SAM.
• These results establish a scalable interface engineering strategy for advancing pure tin tandem perovskite solar architectures.