Artificial light-harvesting systems (LHSs) based on boron-difluoride (BF2) hydrazone complexes (BODIHYs)

Abstract

In the quest to develop artificial light-harvesting systems (LHSs) with high energy transfer efficiency, hydrazone ligands L1–L2 and their –BF₂ complexes (BODIHYs; B1 and B2) have been synthesized. Ligands L1 and L2 and the BODIHYs have been thoroughly characterized by various techniques (¹H, ¹³C, ¹¹B, and ¹⁹F NMR, ESI-MS, UV-vis and fluorescence). Further, the BODIHYs (B1 and B2) have been utilized as a new platform for artificial LHSs. It has been categorically shown that efficient artificial LHSs can be achieved by combining AIEgens B1 and B2 with rhodamine B (RhB) under aqueous conditions. In these systems B1 and B2 serve as a donor while RhB as an acceptor. The calculated energy transfer efficiency and antenna effect for the BODIHYs in combination with RhB came out to be appreciably high (B1 = 68%, 28.7; B2 = 80%, 35.5) at a donor/acceptor ratio of 25 : 1.