| The dissertation deals with the synthesis of inorganic materials in solution system and emphasizes on the preparation of a series of low dimensional nanomaterials, especially the one-dimensional (1D) II-VI and III-V semiconducting compounds, in different novel controllable routes based on the thorough study of the fundamental literatures and the comprehensive understanding of the developments in material synthetic research communities. The synthetic and the growth mechanisms of the prepared nanomaterials, single crystals and thin films along with their microstructure and their properties are also studied in the dissertation, summarized as follows. 1. An improved Ullmann Reaction (IUR) method has been established for the synthesis of nanoscale Cu3P crystallites from a reaction of Cu with triphenyl phosphine (Ph3P) at 300-400 oC, stimulated by the analogizing to the traditional Ullmann coupling route. The synthetic mechanism was presented by various technical characterizations of XRD, TEM, HRTEM, EDS, GCT-MS, FTIR and NMR. The IUR route has been developed as a general synthetic route for the preparation of 1D III-V phosphide semiconductor (InP and GaP) nanowires, from which the metals (In and Ga) are used as both reductants and flux, and Ph3P is served as solvent and reactant in a main solution-liquid-solid (SLS) growth mechanism in solution. The universal rational IUR route has been employed for the preparation of InP thin films on the substrates, and also been adapted for the preparation of the other binary and trinary III-V semiconductor nanocrystals including nitrides and arsenides with aryl nitrides and/or aryl arsenides replacing aryl halides in reaction system. 2. A polyvinyl alcohol (PVA) assisted synthetic route for the preparation of CdSe nanowires mostly in zinc-blende form was reported through a redox reaction of selenite with cadmium salt in ethylenediamine (en) solution at 160 oC. The growth mechanism as well the microstructures and properties of CdSe nanowires have been studied by various techniques. The as-prepared zinc-blende CdSe nanowires in the present route are attributed to a lower reaction temperature comparing with the commonly known wurtzite CdSe and CdTe nanrods and nanowires prepared at a higher temperature (more than 250 oC). The employment of PVA is favorable for the elongating of the short nanorods in en to form long nanowires in an "oriented attachment"growth mechanism. The nanowires shown many interesting shapes (straight, zigzag, helical and hexagrams) and defects (dislocations, stacking faults, twinning, intergrowths and mixed character) are also related to the attachment growth mechanism. Meanwhile, the zinc-blende CdTe nanowires were produced in the same route. Also, a solution deposition of selenides of MSe (M = Cd, Hg) quantum powders has been presented through reactions between metal chlorides and sodium selenosulfate in the ammoniacal aqueous solution at room temperature for 6-10 h. The storage and an interesting phase transition of the MSe nanocrystallites under hydrothermal conditions have been studied in the paper. 3. An organotin precursor solvothermal synthetic route has been established for tin sulphide nanocrystallites. In the route, hexagonal phase SnS2 nanoflakes have been synthesized from reactions between an organotin precursor tetrabutyltin [TBT, (CH2CH2CH2CH3)4Sn] and carbon disulphide in hexanes at 180-200 °C for 10-40 h. The structure, morphologies, composition, and property have been studied. The reaction temperature played an important role on the formation of the SnS2 nanoflakes. This organotin precursor solvothermal synthetic route has also been extended to the SnS2 thin films, which may provide potential application for the technical usage. In addition, hydrothermal and solvothermal synthetic technology has been extended to the growth of a number of single crystals, such as Sb2S3, Sb8O10(OH)2I2 tubular crystals, SbSI and Ag2HgS2single crystals.
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