Multiferroic materials have generated great interest due to their potential as functional device materials. Nanocomposites have been increasingly used to design and generate new functionalities by pairing dissimilar ferroic materials, though the combination often introduces new complexity and challenges unforeseeable in single-phase counterparts. The recently developed approaches to fabricate 3D super-nanocomposites (3D‐sNC) open new avenues to control and enhance functional properties. In this work, we develop a new 3D‐sNC with CoFe2O4(CFO) short nanopillar arrays embedded in BaTiO3(BTO) film matrix via microstructure engineering by alternatively depositing BTO:CFO vertically-aligned nanocomposite layers and single-phase BTO layers. This microstructure engineering method allows encapsulating the relative conducting CFO phase by the insulating BTO phase, which suppress the leakage current and enhance the polarization. Our results demonstrate that microstructure engineering in 3D‐sNC offers a new bottom–up method of fabricating advanced nanostructures with a wide range of possible configurations for applications where the functional properties need to be systematically modified.
The ability to control nanoparticle size, concentration, and distribution in epitaxial nanocomposite films has been a formidable challenge in the synthesis of nanostructured composite materials. Here, a novel 3D super‐nanocomposite (3D‐sNC) architecture is successfully demonstrated by integrating superlattice and vertically aligned nanocomposite structures. In the 3D‐sNC architecture, the feature size and distribution of the nanocylinders such as the height/lateral dimension and the vertical/lateral spacing of nanocylinders can be precisely controlled. The microstructure parameters such as nanocylinder height and spacing modulated interfacial area control the lattice strain, which further tunes the magnetotransport property. These results demonstrate that 3D‐sNC is a simple and yet effective architecture to achieve controlled functionalities via the precise control of nanocylinder size, spacing, concentration, and distribution. Such a 3D‐sNC structure can be used to design advanced nanostructures with desired physical properties for a variety of material systems.
more » « less- NSF-PAR ID:
- 10461541
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Functional Materials
- Volume:
- 29
- Issue:
- 26
- ISSN:
- 1616-301X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Background Water content is a key parameter for simulating tissue swelling and nutrient diffusion. Accurately measuring water content throughout the intervertebral disc (NP = nucleus pulposus; AF = annulus fibrosus) is important for developing patient‐specific models. Water content is measured using destructive techniques, Quantitative MRI has been used to estimate water content and detect early degeneration, but it is dependent on scan parameters, concentration of free water molecules, and fiber architecture.
Purpose To directly measure disc‐tissue water content using quantitative MRI and compare MRI‐based measurements with biochemical assays, and to quantify changes in disc geometry due to compression.
Study Type Basic science, controlled.
Specimen Twenty bone‐disc‐bone motion segments from skeletally mature bovines.
Field Strength/Sequence 7T/3D fast low angle shot (FLASH) pulse sequence and a T2rapid imaging with refocused echoes (RARE) sequence.
Assessment Disc volumes, NP and AF volumetric water content, and T2relaxation times were measured through MRI; NP and AF tissue gravimetric water content, mass density, and glycosaminoglycan content were measured through a biochemical assay.
Statistical Tests Correlations between MRI‐based measurement and biochemical composition were evaluated using Pearson's linear regression.
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