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Hayner, Cary M.

Publications and source records attributed to Hayner, Cary M..

Polymer functionalized graphene oxide and thermally responsive ion permeable membranes made therefrom

Thermally responsive materials, porous membranes comprising the thermally responsive materials, and batteries incorporating the porous membranes as thermally responsive separation membranes are provided. Also provided are methods of making the thermally responsive materials. The thermally responsive materials comprise upper critical solution temperature (UCST) polymers covalently bound to a support substrate.

Kung, Harold H.↗

A low-temperature synthetic route to ternary iron-manganese metal fluorides nanoparticles

Ternary metal fluoride Fe{sub x}Mn{sub 1−x}F{sub 2} (x = 0.00, 0.25, 0.50, 0.75, and 1.00), which is a potential cathode material for next-generation Li-ion batteries, were synthesized via a convenient, low-temperature, bottom-up solution-phase method. The lattice dimensions deduced from X-ray diffraction suggested formation of homogeneous solid solutions. With increasing Fe content, the morphology of the solid changed from cubic particles to dendritic, with an average particle size of 20–40 nm. The results suggested that this synthetic method constitutes a translatable route to large-scale production of ternary metal fluoride nanoparticles. - Graphical abstract: Homogeneous random solid solutions of ternary metal fluoride Fe{sub x}Mn{sub 1−x}F{sub 2} can be prepared by room temperature coprecipitation of precursors followed by drying and calcination at 350 °C. Display Omitted - Highlights: • Homogeneous ternary mixed metal iron-manganese fluoride Fe{sub x}Mn{sub 1−x}F{sub 2} nanoparticles prepared by room temperature coprecipitation and calcination. • Fe{sub x}Mn{sub 1−x}F{sub 2} nanoparticles form different morphology aggregates depending on the composition. • Lattice dimensions from X-ray diffraction suggested formation of homogeneous solid solutions.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

Graphene materials having randomly distributed two-dimensional structural defects

Graphene-based storage materials for high-power battery applications are provided. The storage materials are composed of vertical stacks of graphene sheets and have reduced resistance for Li ion transport. This reduced resistance is achieved by incorporating a random distribution of structural defects into the stacked graphene sheets, whereby the structural defects facilitate the diffusion of Li ions into the interior of the storage materials.

25 ENERGY STORAGE↗