2 research outputs found
Ice Nanoribbons Confined in Uniaxially Distorted Carbon Nanotubes
Water confined inside
nanopores exhibits unusual static and dynamic
properties that depend on the pore size, pore topology, and hydrophobicity
and roughness of the pore walls. The properties also depend on the
geometrical shape of the pore cross sections. Here, we investigated
water inside distorted single-wall carbon nanotubes (SWCNTs) by means
of classical molecular dynamics calculations, over a temperature range
of 100–350 K. SWCNTs, which provide ideal one-dimensional cylindrical
pores with atomically smooth nonpolar walls, were uniaxially compressed
in a direction perpendicular to the SWCNT axes with a deformation
ratio γ up to 60%, where γ represents the ratio of deformation
amount to the initial SWCNT diameter <i>D</i>. With increasing
γ in an SWCNT with <i>D</i> = 1.24 nm, a hexagonal
ice nanotube was converted to the liquid state with high water mobility
down to 200 K and then to a new form of ice, ice nanoribbon, consisting
of four ferroelectric water chains. In an SWCNT with <i>D</i> = 1.51 nm, on the other hand, the water was converted to an ice
nanoribbon with five ferroelectric water chains from the liquid state.
It was demonstrated that the application of uniaxial pressure is a
useful technique to control water properties, such as dielectricity,
mobilities, and structures
Single Chirality Extraction of Single-Wall Carbon Nanotubes for the Encapsulation of Organic Molecules
The hollow inner spaces of single-wall carbon nanotubes
(SWCNTs)
can confine various types of molecules. Many remarkable phenomena
have been observed inside SWCNTs while encapsulating organic molecules
(peapods). However, a mixed electronic structure state of the surrounding
SWCNTs has impeded a detailed understanding of the physical/chemical
properties of peapods and their device applications. We present a
single-chirality purification method for SWCNTs that can encapsulate
organic molecules. A single-chiral state of (11,10) SWCNTs with a
diameter of 1.44 nm, which is large enough for molecular encapsulation,
was obtained after a two-step purification method: metal-semiconductor
sorting and cesium-chloride sorting. The encapsulation of C<sub>60</sub> to the (11,10) SWCNTs was also succeeded, promising a route toward
single-chirality peapod devices