Protein-Templated Magnetic Nanocrystals
Magnetic nanoparticles with narrow size distribution, large magnetic moment and controlled magnetic anisotropy have important technological applications in a wide variety of areas, ranging from data storage and quantum computing, to magnetocaloric refrigeration and cancer therapy. Bio-inspired synthetic routes offer room-temperature pathways to the production of a variety of magnetic nanostructures with exceptional control over nanoparticle formation using biomolecules as matrices, scaffolds and templating agents; this permits the fabrication of magnetic nanocrystals with shapes and sizes not realizable via conventional inorganic chemical techniques. However, despite significant research effort in this area, fundamental understanding of the microscopical mechanisms is lacking on how the supramolecular assembly of biomolecules dictates shape, size and structure of the resulting crystals and how the nucleation and growth processes in biomimetic systems affect functional properties of resulting nanoparticles. Utilizing advanced electron microscopy techniques, the proposed research offers an unprecedented opportunity for determining the nature of macromolecule-mediated nanoparticle formation: i.e., the mechanism of particle nucleation, growth, the emergence of crystal structure and development of ferromagnetism in the individual bio-templated magnetic nanocrystal. Expected experimental findings will be broadly applied to the synthesis of various biomimetic magnetic nanomaterials with controlled and well-defined properties. The proposed work addresses one of the five “Grand Challenges” identified by the DOE BES Advisory Council, specifically: How do remarkable properties of matter emerge from the complex correlations of atomic or electronic constituents and how can we control these properties? The proposed work will lead to the further advancement of the bioinspired methods, and will facilitate rational engineering of various biomimetic magnetic nanomaterials with the properties relevant to the DOE’s mission.
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