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dc.contributor.advisor Whitmire, Kenton H.
dc.creatorWalsh, Sean
dc.date.accessioned 2013-07-24T19:49:52Z
dc.date.accessioned 2013-07-24T19:50:03Z
dc.date.available 2013-07-24T19:49:52Z
dc.date.available 2013-07-24T19:50:03Z
dc.date.created 2012-12
dc.date.issued 2013-07-24
dc.date.submitted December 2012
dc.identifier.urihttps://hdl.handle.net/1911/71699
dc.description.abstract Diamond cuboid-, rhombohedron- and hexagon-shaped nanocrystals as well as branched rods of the solid solution Co1-xMnxO have been synthesized via a solvothermal synthetic route from manganese formate and cobalt acetate at elevated temperature. Rhombohedra and hexagons have dimensions no larger than 50 nm on the longest axis, rods have branches up to 150 nm long and cuboids grow up to 250 nm on a side. X-ray and electron diffraction and transmission electron microscopy analyses show that these nanoparticles are single crystals of wurtzite-type and rock salt-type Co1-xMnxO. Varying the surfactant, water and precursor ratios allows control of particle size, morphology and stoichiometry. Extending growth time at high temperatures (>370°C) leads to the disappearance of the wurtzite phase due to Ostwald ripening. Longer reaction times at temperatures between 345-365°C lead to more crystalline wurtzite-lattice particles. These results show that nanoparticle morphologies and crystal lattices arise from crystal growth and Ostwald ripening at different rates selecting for either small, smooth-surfaced wurtzite lattice particles or large, dendritically-grown rock salt lattice particles.
dc.format.mimetype application/pdf
dc.language.iso eng
dc.subjectWurtzite
Rock salt
Polymorphism
Nanomaterials
Mixed-metal oxide
Solvothermal
Cobalt oxide
Manganese oxide
dc.title Rock Salt vs. Wurtzite Phases of Co1-xMnxO: Control of Crystal Lattice and Morphology at the Nanoscale
dc.contributor.committeeMember Wilson, Lon J.
dc.contributor.committeeMember Wong, Michael S.
dc.date.updated 2013-07-24T19:50:03Z
dc.identifier.slug 123456789/ETD-2012-12-238
dc.type.genre Thesis
dc.type.material Text
thesis.degree.department Chemistry
thesis.degree.discipline Natural Sciences
thesis.degree.grantor Rice University
thesis.degree.level Doctoral
thesis.degree.name Doctor of Philosophy
dc.identifier.citation Walsh, Sean. "Rock Salt vs. Wurtzite Phases of Co1-xMnxO: Control of Crystal Lattice and Morphology at the Nanoscale." (2013) Diss., Rice University. https://hdl.handle.net/1911/71699.


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