Tunable luminescent properties of a europium complex monolayer

Silica substrates were functionalized with a covalent 4-ClCH(2)C(6)H(4)SiCl(3) monolayer. Additional covalent bonding of the tris(dibenzoylmethane) mono(5-amino-1, 10-phenanthroline)europium (III) to the silylated substrates was further achieved. The optical properties of this robust monolayer system were studied at room temperature by both UV-vis and photoluminescence measurements. The UV-vis spectrum, in tune with solution measurements, reveals the presence of the title compound on the film surface. The surface chemical characterization of the monolayer was carried out by X-ray photoelectron measurements and the Eu spectrum shows spin-orbit components of the Eu 3d states. Photoluminescence measurements indicate the presence of two bands at 591 and 614 nm whose intensities can be switched by different light inputs. The adopted synthetic procedure has proven to be effective in transferring molecular properties to a solid state device.