Cucurbit[n]uril-Based supramolecular separation materials

Amidst the swift progression of supramolecular chemistry, supramolecular macrocycles, which are widely recognized as effective guest receptors, particularly in host–guest chemistry, have garnered considerable attention. Cucurbit[n]urils (Q[n]s), as prominent supramolecular macrocyclic host compounds, are characterized with highly symmetrical cages consisting of 2n methylene-bridged n glycosyl urea units. Due to the inherent electrically neutral hydrophobic cavity and the densely packed carbonyl oxygen portals, Q[n]s possess the capability to selectively encapsulate guest molecules within their cavities while also coordinate with metal ions at their portals, which makes cucurbit[n]uril-based separation materials have been extensively applied in adsorptive separation processes. This review summarizes current developments in the utilization of supramolecular materials based on Q[n]s for separating mixed gases, benzene derivatives, metal ions, and various other substances. Furthermore, the prevailing challenges within this research domain are illustrated and a thorough perspective is given for their potential future directions. Based on numerous cutting-edge studies, this review is anticipated to furnish relevant and valuable references for researchers and inspire additional intriguing studies in related fields.