Synthesis and properties of the Inorganic/Organic Hybrid Composite Thin Film by the Liquid-Phase Deposition Method

Abstract

The Copper phthalocyanine (CuPc)/transition metal oxide (TiO₂)-CuPc-SDS/TiO₂ composite thin film has been successfully prepared from the aqueous solution by a novel wet process, liquid-phase deposition (LPD) method. It may open up a new way to prepare the CuPc thin film, and develops the formation processes of CuPc thin films. For LPD method, this is the first attempt to prepare the insoluble organic substance/inorganic metal oxide composite thin film with using a surfactant sodium dodecyl sulfate (SDS) as dispersing agent. The CuPc-SDS/TiO₂ composite thin film was formed directly on to the substrate upon immersion into a mixed solution of [NH₄]₂TiF₆, H₃BO₃ and CuPc-SDS aqueous solution. The deposited composite thin films were characterized by ultraviolet-visible (UV-Vis) absorption spectroscopy in the range of 350-850 nm, scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD) and inductive coupled plasma atomic emission spectrometry (ICP-AES). The results revealed that most of the CuPc existed as dimer species both in the film and in the treatment solution, illustrating that the CuPc is not further aggregated by LPD process. According to the study of the XRD patterns of the composite thin films, the CuPc-SDS/TiO₂ composite thin film was proved to be α-form CuPc composite thin film. The effects of changing SDS and CuPc concentration on the composite thin films were studied, indicating that the deposited amount of CuPc increased with an increase of SDS and CuPc concentrations. The dependences between the deposited amount of Ti and Cu with the reaction time were investigated, which indicated that the deposited amount of Ti and Cu are nearly directly proportional to the reaction time, and suggested the growing of the composite thin film was controllable readily.