An Efficient Near-Infrared Emissive Artificial Supramolecular Light-Harvesting System Based on Cyanovinylene-Cored Dendrimers in Aqueous Solution

Langmuir. 2025 Jun 29. doi: 10.1021/acs.langmuir.5c02301. Online ahead of print.

Abstract

Light-harvesting systems play a pivotal role in capturing, transferring, and utilizing solar energy. While significant progress has been made in visible-light harvesting, the development of highly efficient artificial light-harvesting systems (ALHSs) with near-infrared (NIR, 650-900 nm) emission remains a formidable challenge. In this work, we report a breakthrough in aqueous-phase NIR-emissive light-harvesting systems through supramolecular coassembly of cyanovinylene-cored dendrimers (CV-1, CV-2) and NIR-emitting dye MTSIC. The CV dendrimers exhibit remarkable aggregation-induced emission enhancement (AIEE) characteristics, serving as excellent energy donors. When assembled with MTSIC acceptors, the resulting system demonstrates efficient NIR emission at 780 nm. Notably, the CV-1-MTSIC system achieves exceptional energy transfer efficiency (ΦET = 43.4%) and antenna effect (AE = 16.7) even at an ultrahigh donor/acceptor ratio of 500:1. Furthermore, we successfully engineered white-light-emitting materials in aqueous media by employing tetraphenylethylene donors and dendritic acceptor CV-2, with precisely optimized THF/water solvent ratios and stoichiometric control. This study not only provides valuable insights into NIR-emissive supramolecular ALHSs but also establishes AIEE-active dendrimers as versatile platforms for advanced light-harvesting applications, particularly in biomedical fields such as NIR bioimaging, theranostics, and photodynamic therapy.