Phototriggered NO and CN release from [Fe(CN)(5)NO](2-) molecules electrostatically attached to TiO2 surfaces

Abstract

Phototriggered NO and CN release from [Fe(CN)(5)NO](2-) (NP) molecular monolayers is studied by a combination of electrochemistry, infrared spectroscopy, and mass spectrometry under light irradiation at temperatures of 80 K and 294 K. The NP molecular monolayers were electrostatically attached to thin films of mesoporous TiO2 deposited on silicon. Irradiation of the surfaces results in NO and CN release, which is verified using mass spectrometry. The kinetic trace of the light driven NO release of the [Fe(CN)(5)NO](2-) is determined by inspection of the nu(NO) stretching mode as a function of exposure to light in the violet/green spectral range. The decrease of the nu(NO)-amplitude can be modeled considering the NO release as a two-step process with an intermediate state between the attached and the released state. According to literature, the intermediate state may be related to the light-induced linkage NO isomerization of the NP.