nor-seco-Cucurbit[10]uril-based Supramolecular Assembly for Ultralong Afterglow Room-Temperature Phosphorescence Material and Metal Ion Detection

A multifunctional supramolecular assembly, comprising nor-seco-cucurbit[10]uril (ns-Q[10]) and tripyridine-bridged 4-(4-bromophenyl)pyridine (BTPY), has been constructed. The host–guest interaction between BTPY and ns-Q[10] resulted in a decrease in the singlet–triplet splitting energy (ΔEST), thereby enhancing the intersystem crossing process. Furthermore, the multiple hydrogen bonding interactions between BTPY@ns-Q[10] assembly and poly(vinyl alcohol) (PVA), as well as its own host–guest interaction, inhibited the nonradiative transitions, resulting in long-lived room temperature phosphorescence (RTP) (τ = 261.3 ms). This RTP material provided a potential method for constructing RTP materials for information encryption and anticounterfeiting through a host–guest strategy. Moreover, the terpyridine component of BTPY, known for its strong metal coordination ability, enables the BTPY@ns-Q[10] assembly to rapidly detect Fe2+ and Fe3+ ions in aqueous solution.