A Pillar[6]arene-Based Solid-State Supramolecular Polymer Exhibiting a Vapochromic Response for VOC Detection

Solid-state
supramolecular polymers based on exo-wall
macrocycle-guest
complexation are promising for designing functional materials. In
this work, we investigate the host–guest complexation of perethylated
pillar[6]arene (EtP6) with halogenated guests tetrafluorophthalic
anhydride, tetrachlorophthalic anhydride, and tetrabromophthalic anhydride. EtP6 exhibits relatively strong binding affinity toward these
guests via charge-transfer interactions. Notably, leveraging the exo-wall
complexation between EtP6 and tetrachlorophthalic anhydride,
we constructed a linear solid-state supramolecular polymer. By exploiting
the unoccupied cavity of EtP6 and the structural rearrangement
of the supramolecular polymer, we achieved efficient vapochromic detection
and adsorption of a broad range of volatile organic compounds (VOCs).
This study not only introduces a solid-state supramolecular polymer
but also provides an innovative strategy for designing vapochromic
materials for VOC sensing and capture, demonstrating significant potential
for environmental monitoring and health protection applications.