Highly ordered luminescent calix[4]azacrown films showing an emission response selective to volatile tetrahydrofuran

Sensitive, selective, low-cost, and simply designed detectors for THF among other vapour organic compounds (VOCs) are highly attractive. Self-assembled molecular films with remarkable selective vapoluminescent response to VOC THF were fabricated using drop-casting of calix[4]azacrown-based J-aggregates. The latter, stabilized viaC-H... pi and C-H...O hydrogen bond networks, assemble into nanoparticles that exhibit aggregation-induced emission (AIE) effect, which produces violet emission at room temperature in acetonitrile. The films are highly ordered and switch order at high temperature, leading to 2.5-fold luminescence enhancement and responsive behaviour.