Raman spectroscopy of zinc oxide nanoplatelets modified with ruthenium (II) complexes

We analyzed and compared the unmodified and three modified zinc oxide nanoplatelet materials. The three components used in zinc oxide modification were the 4,4'-bipyridine and two ruthenium (II) complexes, namely, the trans-[Ru (bpy)(bpyCOO)Cl-2](2-) and cis-[Ru (bpy)(bpyCOO)Cl-2](2-). The obtained results revealed that after modification, ZnO nanoplatelets became smaller and embedded in the materials used for the modification. When ZnO was modified with either of the two ruthenium (II) complexes, the interaction between them led to a higher activity of ZnO. The metal-to-ligand charge transfer that was also detected in the two cases of ZnO nanoplatelets modified with the ruthenium (II) complexes caused significant alteration of the Raman spectrum and consequent changes of the optical properties. Various forms of ruthenium (II) complexes were used in several published studies related to dye-sensitized solar cells and biomedicine. The biomedical applications include, for example, the ATP (adenosine-5'-triphosphate) detection, interaction with human serum albumin, DNA analysis, and cancer detection and treatment. The properties of the ZnO nanoplatelets modified with the two ruthenium (II) complexes presented here indicate that it may be worth exploring if the studied materials are applicable in the dye sensitized solar cells and biomedicine. Possible advantage of our results is that they were obtained at room temperature.