This study proposes a "fine molecular engineering" strategy to address the trade-off between efficiency and stability by designing non-fullerene acceptors (NFAs). Based on 7C-2F with a 1,4-diazahexane core, three NFAs  were synthesized by selectively controlling the side chain length and the degree of π-conjugation of the terminal groups. The results show that shortening the side chain (7C-BO-2F and 7C-eC9-2F) or extending the π-conjugation of the terminal groups (7C-N2F) both improve molecular crystallinity, shorten the π-π stacking distance, and suppress nonradiative energy loss. In bulk heterojunction devices, the PM6:7C-eC9-2F system achieved a PCE of 19.67% with an energy loss of only 0.539 eV. Devices based on 7C-eC9-2F exhibit excellent photostability and thermal stability: under continuous illumination, the device's T₈₀ reaches 2728 h⁻¹; at 65 °C, its T₈₀ reaches 1242 h⁻¹, significantly outperforming other control systems. Furthermore, when these acceptors are applied to quasi-planar heterojunction structures, excellent photovoltaic performance is also obtained, demonstrating good fabrication adaptability. In summary, precise molecular engineering provides a reliable pathway to obtaining high-efficiency, low-energy-loss, and intrinsically stable OPVs, laying the foundation for the practical application of next-generation organic photovoltaic devices. The article was published as an open access Research Article in CCS Chemistry, the flagship journal of the Chinese Chemical Society.

Agriculture is one of the most dangerous occupations in the United States. Each year, vehicles, machinery, environmental hazards, and other incidents cause thousands of injuries and hundreds of fatalities. A thorough understanding of the main risks is key to preventing accidents and promoting agricultural safety. A research team at the University of Illinois Urbana-Champaign has developed an interactive platform that allows users to obtain customized information about agricultural injuries. The researchers describe their work in a new article.

A microscopic worm that has no kidneys is helping Rutgers scientists understand a genetic change suspected of causing a serious inherited kidney disease.

Roboticists at the UCLA Samueli School of Engineering and the University of Michigan have shown that elastic rods can be bent and twisted to repeatedly snap between shapes, releasing built-up energy that enables small robots to hop, flip and swim. The study, published in Science Advances, could offer a promising new approach to movement for robots constrained by size, weight and power output. The snapping mechanism could also help robots move across uneven terrain, on land and in water.