The Exploration On Chemical Vapor Deposition Precursor Of Rhenium

Because of the excellent high temperature mechanical properties, remarkable corrosion resistance, excellent abrasive resistance and room temperature plasticity characteristics, the rhenium and its alloys are widely used in a variety of cutting-edge areas of science and technology in the domestic and overseas. For instance the national defense, electronics, aerospace and new material and so on.Rhenium processing technic is relatively complex, and the chemical vapor deposition (CVD) is has the superiority for the preparation of refractory metal.By means of chemical vapor deposition can be directly obtained from the raw materials on the desired metal material, avoiding the cumbersome processing step. Chemical vapor deposition process is generally in the sealing of the vacuum system, little impurities, high purity products obtained density close to the theoretical value, which is difficult to achieve by other processes.In view of the current chemical vapor deposition of the precursor of rhenium shortcomings,this paper seeks to the preparation of the new synthesis process of rhenium chemical vapor deposition precursor,which is simple, easy to store and environmentally.In this thesis, rhenium powder as the starting material the synthetic intermediates potassium hexachlororhenate(IV)(K2ReCl6), and to study the effects of different temperature, chlorine flow for potassium hexachlororhenate(IV) synthesis,to determine the optimal parameters of the reaction. Among potassium hexachlororhenate(IV) as raw material, the use of organic synthesis method to explore the preparation of a variety of chemical vapor deposition precursor of rhenium.In the process of exploration, a fuchsia rhenium acetylacetonate complexes, which is soluble both in water and alcohol, that has never been mentioned neither in the Chinese literatures nor in foreign ones.To determine the product’s structure and properties,it is characterized by infrared spectroscopy, UV spectroscopy, NMR, mass spectrometry and ICP-AES.And according to the experimental pHenomenon of the synthesis process, the treatise discuss the reaction mechanism of this synthesis.Research the compound according to the thermogravimetric analysis(TGA)-differential thermal analysis(DTA),thereby further determining the possibility of such a new compound is used as a precursor for chemical vapor deposition of rhenium.Bis[oxobis(acetylacetone)rhenium] which is synthesize in the exploration and research, readily available raw materials, the synthesis process is simple, suitable thermodynamic properties. The compound has the prospect to be a precursor chemical vapor deposition as rhenium.Preparation of rhenium in trifluoroacetic acid complexes of experimental research, in the process of synthesis of the waterinsoluble white powder, the detection of the compound is potassium perrhenate. Due to the poisonousness of potassium perrhenate and its high melt boiling point, the compound is unfavorable to the chemical vapor deposition of precursor.