Synthesis of dispersible nanostructures using anti-sintering cast materials

[摘要] At the elevated temperatures required for metal carbide synthesis, atomic diffusion across particle boundaries can occur, resulting in the fusion of smaller particles into larger ones. This process is termed sintering. By providing a physical barrier for the inhibition of sintering, in the form of easily removable alkaline earth metal oxide “cast materials”, this thesis shows that Prussian Blue nanoparticles can undergo thermal decomposition to produce discrete Fe3C nanoparticles. The overarching aim of this work is to push the boundaries of metal carbide synthesis by forming the basis of a technique that can eventually be applied to the synthesis of a wide range of discrete metal carbide nanostructures. A combination of energy dispersive X-ray analysis and electron tomography provides evidence of efficient dispersal of Fe3C nanoparticles throughout various cast materials and ample evidence of <100 nm Fe3C particle diameters. Scanning electron microscopy provides evidence of the ability to disperse these particles over a catalyst support, and superconducting quantum interference device measurements show superparamagnetic behaviour for the Fe3C particles. The technique is then extended to larger size regimes in the biotemplating of carbonised microcoils using the algae species spirulina.

[发布机构] University:University of Birmingham;Department:School of Chemistry

[关键词] Q Science;QD Chemistry