In situ control of multicolor luminescence over the entire visible spectral region in a single chromophore by sol-gel transformation and dynamic metal-ligand coordination

Abstract

Controlling multicolor luminescence in a single chromophore is of fundamental significance but remains a great challenge. In this study, a carbazole group was incorporated into terpyridine through acylamide to produce a novel chromophore (N-{4-[(2,2′:6′,2″terpyridine)-4′-yl]benzyl}-9-hexyl-9H-carbazole-3-carboxamide, TBCC) for achieving programmable luminescence switches. Significantly different emission states, such as nonemissive, blue, green, yellow, red, and white, were achieved in situ by controlling sol-gel transformation with sonication/heat and the reversible metal-ligand coordination between TBCC and various metal salts. Based on this feature, an interacting network for multistate switching among six distinct emissive states was successfully constructed. Potential applications of the communicating network have been demonstrated for reversible multicolor encoding and decoding. These findings can be useful in the studies of molecular switches, dynamic assemblies, and smart materials.