Nano-structured metals and inter-metallic phases have a wide range of applications including; magnetic sensors and memories, chemical and mechanical protection, catalysis and as electrode materials. Therefore versatile, low temperature, low cost routes to nano-structured metals and alloys as thin films, coatings and sponges are of high industrial interest. A new route using homogeneous solutions of metal nitrates and acetates complexed with triethanolamine has been developed. On heating to 100-500oC under nitrogen atmosphere nano-structured metal films, dense pieces or highly porous sponges of metal with crystallite sizes down to ca 3-6 nm for nickel (1) and cobalt (2) could be obtained.
In this study we continue with an investigation of formation of Ni-Co phases in thin film and porous powder forms. The conversion to homogenous nano-structured metal alloys was monitored by thermo-gravimetric analysis and differential scanning calorimetry for several compositions and heating rates and the sintering of nano-crystalline intermetallics to larger crystallites were investigated with powder and grazing incidence X-ray diffraction techniques, SEM and TEM-EDS. The magnetic properties of the films and powders were investigated on their magnetic properties with SQUID and magnetic susceptometry.
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