Selective Vapochromic Recognition of Benzene/Cyclohexane by a Clamparene-Based Charge-Transfer Supramolecular Polymer in the Solid State

Abstract

Organic cocrystals have emerged as a cutting-edge strategy for constructing high-performance organic functional materials, with their significance in materials science increasingly prominent. This study successfully constructed a charge transfer (CT) eutectic system using electron-rich clamparene (CLP) as the host and electron-deficient naphthalene-diimide-functionalized diol (NDI-diol) as the guest. This was achieved by leveraging the charge complementary properties between the host and guest molecules and the π–π stacking and C–H···π interactions. This eutectic material exhibits outstanding thermal stability and demonstrates highly specific gas-induced color-changing response to benzene vapor, while showing no significant optical response to cyclohexane vapor. Its selective sensing mechanism originates from the microreconstruction of the crystal structure triggered by benzene molecule adsorption and the resulting modulation effect of CT interactions between the host and guest molecules. This study provides a research paradigm for the design of highly selective benzene-based detection materials.