Synergistic Modulation of Orientation and Steric Hindrance Induced by Alkyl Chain Length in Ammonium Salt Passivator Toward High-performance Inverted Perovskite Solar Cells and Modules.

Organic ammonium salts are extensively utilized for passivating surface defects in perovskite films to mitigate trap-assisted nonradiative recombination. However, the influence of alkyl chain length on the molecular orientation and spatial steric hindrance of ammonium salt remains underexplored, hindering advancements in more effective passivators. Here, a series of organic ammonium salts is reported with varying alkyl chain lengths to passivate surface defects and optimize band alignment.

Managing Pb-Related Imperfections via Rationally Designed Aniline Derivative with Bilateral Cyano and Acetyl Groups as Lewis Base for High-Efficiency Perovskite Solar Cells Exceeding 24.

Pb-related imperfections (surface or halide vacancy induced uncoordinated Pb, Pb-I antisite, and Pb vacancy defects) of the ionic crystal perovskite film seriously restrict the photovoltaic performance of perovskite solar cells (PSCs). Here, an aniline derivative N-(4-cyanophenyl)acetamide (CAL) is rationally designed, incorporating bilateral functional sites of cyano and acetyl groups, acting as Lewis base molecule for managing the Pb-related imperfections in perovskite surface through post-treatment. Theoretical calculation and experimental verification together proved the reduced defect density, improved crystallinity, and inhibited ion migration in the CAL-modified perovskite.

Synchronous Regulation Strategy of Pyrrolidinium Thiocyanate Enables Efficient Perovskite Solar Cells and Self-Powered Photodetectors.

Developing inventive approaches to control crystallization and suppress trap defects in perovskite films is crucial for achieving efficient perovskite photovoltaics. Here, a synchronous regulation strategy is developed that involves the infusion of a zwitterionic ionic liquid additive, pyrrolidinium thiocyanate (PySCN), into the perovskite precursor to optimize the subsequent crystallization and defects. PySCN modification not only orchestrates the crystallization process but also deftly addresses trap defects in perovskite films.