Xueliang Yu

Organic solar cells, as a cutting-edge sustainable renewable energy technology, possess a myriad of potential applications, while the bottleneck problem of less than 20% efficiency limits the further development. Simultaneously achieving an ordered molecular arrangement, appropriate crystalline domain size, and reduced nonradiative recombination poses a significant challenge and is pivotal for overcoming efficiency limitations. This study employs a dual strategy involving the development of a novel acceptor and ternary blending to address this challenge. A novel non-fullerene acceptor, SMA, characterized by a highly ordered arrangement and high lowest unoccupied molecular orbital energy level, is synthesized. By incorporating SMA as a guest acceptor in the PM6:BTP-eC9 system, it is observed that SMA staggered the liquid-solid transition of donor and acceptor, facilitating acceptor crystallization and ordering while maintaining a suitable domain size. Furthermore, SMA optimized the vertical morphology and reduced bimolecular recombination. As a result, the ternary device achieved a champion efficiency of 20.22%, accompanied by increased voltage, short-circuit current density, and fill factor. Notably, a stabilized efficiency of 18.42% is attained for flexible devices. This study underscores the significant potential of a synergistic approach integrating acceptor material innovation and ternary blending techniques for optimizing bulk heterojunction morphology and photovoltaic performance.

Polymers represent a promising therapeutic platform for extrahepatic messenger RNA (mRNA) delivery but are hampered by low in vivo efficacy due to polyplex serum instability and inadequate endosomal escape following systemic administration. Here, we report the rational design and combinatorial synthesis of zwitterionic phospholipidated polymers (ZPPs) via cationic polymer postmodification by alkylated dioxaphospholane oxides to deliver mRNA to spleen and lymph nodes in vivo. This modular postmodification approach readily produces tunable zwitterionic species for serum resistance and introduces alkyl chains simultaneously to enhance endosomal escape, thereby transforming deficient cationic polymers to efficacious zwitterionic mRNA carriers without the need to elaborately synthesize functional monomers. ZPPs mediated up to 39 500-fold higher protein expression than their parent cationic counterparts in vitro and enabled efficacious mRNA delivery selectively in spleen and lymph nodes following intravenous administration in vivo. This zwitterionic phospholipidation methodology provides a versatile and generalizable postmodification strategy to introduce zwitterions into the side chains of cationic polymers, extending the utility of cationic polymer families for precise mRNA delivery and demonstrating substantial potential for immunotherapeutic applications.