Luminescence of Macrocyclic Mononuclear Dy III Complexes and Their Immobilization on Functionalized Silicon-Based Surfaces.

Two mononuclear Dy complexes, [Dy(L)(NCS)] () and [Dy(L)(NCS)] (), where L ( = 1-2) corresponds to a macrocyclic ligand derived from 2,6-pyridinedicarboxaldehyde and ethylenediamine (L) and 1,3-diaminepropane (L) were immobilized on functionalized silicon-based surfaces. This was achieved by the microcontact printing (μCP) technique, generating patterns on a functionalized surface via covalent bond formation through the auxiliary -NCS ligands present in the macrocyclic complex species. With this strategy, it was possible to control the position of the immobilized molecules on the surface. Water contact angle measurements, X-ray photoelectron spectroscopy (XPS), infrared reflection absorption spectra (IRRAS), and atomic force microscopy (AFM) confirmed that the surfaces were successfully functionalized. Furthermore, the optical properties in a broad temperature range were investigated for the as-prepared compounds. At room temperature, was shown to emit in the deep blue region (Commission Internationald'Eclairage (CIE): (0.175, 0.128)), while in the white region (CIE: (0.252, 0.312)). The different CIE values were due to the contribution of the strong emission of the ligand in the case of . Besides, surface photoluminescence measurements showed that the immobilized complexes retained their bulk emissive properties.