Synthesis and Characterization of Triphenylene-BODIPY Paddle Wheel Conjugates for Ultra-Fast Light Induced Charge Separation Yielding High-Energy Charge-Separated States

• Main Author: Cantu, Robert
• Other Authors: D'Souza, Francis
• Format: Others
• Language: English
• Published: University of North Texas 2019
• Subjects: BODIPY; donor-acceptor; Triphenylene
• Online Access: https://digital.library.unt.edu/ark:/67531/metadc1505171/

In the development of covalent organic frameworks (COFs), often the scaffold linkers are assumed to be electro- and photoinactive, and this was also to be the case for 2,3,6,7,10,11-hexahydroxytriphenylene, a tritopic linker. However, as demonstrated in the present study, the reaction product of this linker, hexaoxatriphenylene, is electron rich and when connected to a suitable photosensitizer engages itself in an efficient excited-state charge separation process. In the present study, we have employed BF2-chelated dipyrromethenes (BODIPYs) as sensitizers, which are connected to hexaoxatriphenylene through the center boron, rendering paddle-wheel-type structures. Systematic photophysical, electrochemical, computational, and photochemical studies involving pump-probe femtosecond transient spectroscopy have been performed to establish efficient charge separation in these novel supramolecular structures.