摘要： Hybrids nanostructures with switchable and reversible “blue-red-green” emission were efficiently synthesized. The Polyhedral Oligomeric Silsesquioxane (POSS) behaves as a directional nano-cage for the terpyridine-based organic ligands allowing an easy complexation of Europium (III) cations. The complexes were characterized via UV-Vis and fluorescence spectroscopies and the stoichiometry was also confirmed via 1H NMR investigation. The octafunctionalized nano-cages allow forming novel self-assembled 3D architectures in presence of the lanthanide cation displaying a red-emission of particular intensity especially in solid state. The presence of an alkenyl group bridging the inorganic core to the organic moiety was employed to tune the emission properties via trans-cis isomerization of the double bond. In the case of O-POSS nanocages this isomerization was monitored also in presence of Eu(III) cations and was accompanied by an evident modification of the colour which passed from blue (trans-O-POSS) to red (Eu@trans-O-POSS) and finally to green (cis-O-POSS) as consequence of the release of the metal cations. This behaviour, together with the easy dispersion of the dry powder and the possibility of coating it as a film in presence of small amount of solvent, makes the emitting solid promising for applications in materials science.