Modified side-chain COFs construct built-in electric fields with low exciton binding energy for photo-reduced uranium

Integrating Uranyl-Affinity “Hooks” into Conjugated Polymers Achieving Giant Built-in Electric Field for Boosting Photocatalytic Uranium Extraction from Seawater

“…An important breakthrough in overcoming the above challenges is to regulate the built-in electric field (IEF) by controlling the dipole moment of repeating units in conjugated polymers, in which the IEF has been certified to be the critical kinetic factor to determine PCS efficiency. − For example, Zhu and co-workers increased the asymmetry of the oligomer structure by introducing carboxyl groups into polymer side chains, which significantly increased the molecular dipole, thus enhancing the IEF and realizing desirable photocatalytic activity . Furthermore, donor–acceptor/donor−π–acceptor (D-A/D-σ-A/D-π-A) structures with larger π-electron delocalization to increase the dipole moment can also enhance the built-in electric field and facilitate charge separation and transport, thus remarkably promoting photocatalytic performances. − …”