From a bulk solid to thin films of a hybrid material derived from the [Ti10O12(cat)8(py)8] oxo-cluster and poly(4-vinylpyridine)

Abstract

In this work, we report the formation of a coloured inorganic–organic hybrid material generated from the [Ti10O12(cat)8(py)8] (catecholato (cat), pyridine (py)) oxo-cluster and poly(4-vinylpyridine). The titanium oxo-cluster is linked to the organic polymer through Ti–N coordination bonds. Vibrational spectroscopies (FT-IR and Raman scattering) and thermogravimetric analysis highlight the quantitative incorporation of the cluster in the polymeric matrix with no degradation of the inorganic core of the starting complex, and also highlight the good homogeneity of the resulting materials. Solid-state NMR measurements (13C CP-MAS) also reveal that the hybrid material results only from the substitution of the labile pyridine ligands within [Ti10O12(cat)8(py)8] by the pyridines of the P4VP polymer. Next, the functionalization of SiO2 surfaces with monolayer or multilayer films composed of alternate layers of the oxo-cluster and of the polymer is detailed. The thickness of these films, as evaluated by ellipsometry, ranges from a few nanometers to tens of nanometers for the monolayer films and the multilayer films, respectively.