2 research outputs found
Directed Growth of Virus Nanofilaments on a Superhydrophobic Surface
The
evaporation of single droplets of colloidal tobacco mosaic virus (TMV)
nanoparticles on a superhydrophobic surface with a hexagonal pillar-pattern
results in the formation of coffee-ring type residues. We imaged surface
features by optical, scanning electron, and atomic force microscopies.
Bulk features were probed by raster-scan X-ray nanodiffraction. At
∼100 pg/μL nanoparticle concentration, the rim of the
residue connects to neighboring pillars via fibrous extensions containing
flow-aligned crystalline domains. At ∼1 pg/μL nanoparticle
concentration, nanofilaments of ≥80 nm diameter and ∼20
μm length are formed, extending normal to the residue-rim across
a range of pillars. X-ray scattering is dominated by the nanofilament
form-factor but some evidence for crystallinity has been obtained.
The observation of sheets composed of stacks of self-assembled nanoparticles
deposited on pillars suggests that the nanofilaments are drawn from
a structured droplet interface
Tunable Strain in Magnetoelectric ZnO Microrod Composite Interfaces
The
intrinsic strain at coupled components in magnetoelectric composites
plays an important role for the properties and function of these materials.
In this in situ X-ray nanodiffraction experiment, the coating-induced
as well as the magnetic-field-induced strain at the coupled interface
of complex magnetoelectric microcomposites were investigated. These
consist of piezoelectric ZnO microrods coated with an amorphous layer
of magnetostrictive (Fe<sub>90</sub>Co<sub>10</sub>)<sub>78</sub>Si<sub>12</sub>B<sub>10</sub>. While the intrinsic strain is in the range
of 10<sup>–4</sup>, the magnetic-field-induced strain is within
10<sup>–5</sup>, one order of magnitude smaller. Additionally,
the strain relaxation distance of around 5 μm for both kinds
of strain superposes indicating a correlation. The value of both intrinsic
and magnetic-field-induced strain can be manipulated by the diameter
of the rodlike composite. The intrinsic interface strain within the
ZnO increases exponentially by decreasing the rod diameter while the
magnetic-field-induced strain increases linearly within the given
range. This study shows that miniaturizing has a huge impact on magnetoelectric
composite properties, resulting in a strongly enhanced strain field
and magnetic response