Solvothermal Growth And Properties Of Crystalline Films Of Metal Sulfides

Solvothermal synthesis, has been widely used in scientific fields and industrial productions. Up to now, a large number of inorganic and inorganic-organic hybrid materials have been prepared by this effective synthetic technique and it will attract more and more attention. However, to the best of our knowledge, fabrication of inorganic microcrystal(nanocrystal) films on the reactive substrate (metal substrate) via a solvothermal route is a new method for preparation of films. In this work, we prepared microcrystal (nanocrystal) films with various morphologies under solvothermal condition. Four films of Cu2S, Cu2Se, Ni3S2 and Ni-TCNQ were successfully deposited on the corresponding metal surfaces. The major contents of the research are as follows:1,In introduction, film materials and their preparation methods have been introduced briefly. The research progress of preparation of the film materials on metal substrates, such as Zn, Cu, Ag, Fe, Ni, Sn, Pb and Ti, under solvothermal condition has been discussed. Finally, surfactant and the role of surfactant in the fabrication of nano-material described briefly.2,In chapter 2, Cu2S films were successfully deposited on the copper foil by reaction of copper, sulfur powder in ethylenediamine under solvothermal conditions,with the assistance of surfant of CTAB. The films were characterized by X-ray diffraction, SEM, TEM and UV-vis spectra. We found that CTAB plays an important role in the growth of the Cu2S films. In the presence of CTAB, the reaction time is significantly shortened. The film prepared with the assistance of CTAB showed a compact and uniform crystalline structures. The main advantages of this method to prepare Cu2S films are its convenience in manipulation.3,In chapter 3, Cu2Se (JCPDS NO. 47-1448) films were successfully deposited on the copper substrate by treatment of copper foil in Se/hydrazine-hydrate, Se/en or Se/ammonia-liquor, respectively, under solvothermal condition with or without the assistance of surfactant CTAB or PEG-6000. The films were characterized by methods of XRD, SEM, TEM and UV-vis spectra. Films of Cu2Se with hexagonal microcrystals can be obtained in hydrazine reaction system. When CTAB is added, the film is composed of thin leaf-like microcrystals. When ethylenediamine (en) is used as a solvent, the leaf-like microcrystals are crimped.4,In chapter 4, Ni3S2 (JCPDS NO. 44-1418) films with regular morphologies were successfully deposited on the nickel substrate by treatment of nickel foil in S/hydrazine-hydrate, S/NaCl solution, S/H2O, S/en, S/diethylenetriamine, respectively, under solvothermal condition with or without the assistance of surfactant CTAB or PEG-6000 or SDBS. In all the cases the films were characterized as the same Ni3S2 phase. The morphologies of the films couild be changed by adjustment of the reaction parameters.5,In chapter 5, Ni-TCNQ films with rod-like and ball-like morphologies were successfully deposited on the nickel substrate by treatment of nickel foil in acetonitrile solution of TCNQ , under solvothermal condition. It was found that the morphologies of the films were affected by the reaction conditions including solvents, reaction time and so on. In all the cases the films were characterized as the same Ni-TCNQ phase.