Controllable vapor phase fabrication of F:Mn3O4 thin films functionalized with Ag and TiO2

A facile two-step vapor phase synthetic approach is proposed for the fabrication of Mn3O4 thin films chemically modified with fluorine, and eventually functionalized with silver or titania. The adopted strategy exploits the initial chemical vapor deposition (CVD) of Mn3O4 on Si(100) substrates starting from a diamine diketonate MnIJII) complex, followed by the controlled radio frequency (RF)-sputtering of silver or titania. Complementary analytical techniques were employed to investigate the crystallinity (X-ray diffraction), chemical composition (X-ray photoelectron spectroscopy, secondary ion mass spectrometry, energy dispersive X-ray spectroscopy), morphology and nano-organization (field emission-scanning electron microscopy, atomic force microscopy, transmission electron microscopy) of both pristine and functionalized manganese oxide thin films. Under the adopted operating conditions, the target MnIJII) complex acted as a single-source precursor for both Mn and F, leading to the formation of phase-pure hausmannite Mn3O4 films characterized by a uniform in-depth fluorine content. In addition, the obtained results gave evidence of the formation of high purity Ag/F:Mn3O4 and TiO2/F:Mn3O4 composites with a close contact between the single constituents. This work outlines an amenable and efficient method for the vapor phase growth of composite Mn3O4-based thin films, which are favorable candidates for diverse technological applications, from photocatalysis to gas sensing.