Room‐Temperature Phosphorescence and Reversible White Light Switch Based on a Cyclodextrin Polypseudorotaxane Xerogel

Abstract The development of metal‐free room‐temperature phosphorescent (RTP) and white‐light‐emitting supramolecular materials is significant for artificial soft materials. Herein, a polypseudorotaxane xerogel is fabricated by threading a linear brominated aromatic aldehyde polymer into α‐cyclodextrin cavities. The xerogel can be excited to produce not only RTP signals based on the xerogel network structure's strong restriction of phosphor vibrations and suppression of the nonradiative relaxation process but also white‐light emission at room temperature. Notably, the polypseudorotaxane system possesses excellent fluorescence–phosphorescence dual emission properties and is capable of reversible photoluminescence switching between blue fluorescence emission and white‐light emission in the presence and absence of water.