A novel method for the electrochemical synthesis of titanium nitride thin films and powders has been developed. This involves the anodisation of an oxide-free titanium electrode in a solution of potassium amide in liquid ammonia. The system is inherently free from carbon-, halide- and oxygen-containing contaminants. At -78°C and atmospheric pressure coherent films of titanium nitride are produced, which adhere very well to the substrate. The amount of charge passed may be used to control the thickness of the resulting film. The films have been characterised by electrochemical studies, scanning electron microscopy with energy dispersive x-ray spectroscopy, Raman spectroscopy, magnetic and reflectance measurements, microhardness testing and x-ray photoelectron spectroscopy. A thick-walled pressure cell has been constructed in order to contain liquid ammonia at 25°C at a pressure of 10 bar. Operation under these conditions favours the synthesis of nano-particulate powders. The powders have been characterised by scanning electron microscopy with energy dispersive x-ray spectroscopy, Raman spectroscopy, transmission electron microscopy and electron diffraction. The method has also been extended to the synthesis of molybdenum, tungsten, tantalum, aluminium and iron nitrides. A new route for the electrodeposition of titanium metal has also been designed. The precursor K<sub>3</sub>[Ti(SCN)<sub>6</sub>] in acetonitrile solution or dissolved in a novel 1-butyl-3-methylimidazolium thiocyanate 'ionic liquid', has been used to deposit titanium on copper or iron under ambient conditions. The films have been characterised by electrochemical studies and SEM-EDXS.
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:651830 |
| Date | January 2000 |
| Creators | Griffiths, Lucy E. |
| Publisher | University of Edinburgh |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Source | http://hdl.handle.net/1842/13961 |
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