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As nanotechnologies developed, the researchers proceeded to
investigations of carbonic nanoelements – nanotubes, nanofibers,
nanocones, which possess unique properties to absorb various gases.
The hydrogen quantity in such systems depends on adsorptive properties
of nanostructures, pressure and environmental temperature. Their main
advantage is the ability to store hydrogen at low pressure. Although
this did to come to application yet, the researchers are carrying out
theoretical study. In general, they came to studying nanotubes’
properties. It has turned out that they are theoretically capable to
accumulate five to ten percent of hydrogen at the temperature of 77
Kelvin degrees - the boiling temperature of nitrogen.
The researchers from the Institute of Applied Mechanics, Ural Branch
of Russian Academy of Sciences, believe that absorbing properties of
fullerenes and other nanostructures that include fullerenes have not
been fully investigated. Therefore, they set a problem: to study the
influence of thermodynamic parameters – pressure and temperature – on
the process of molecular hydrogen absorption by such nanosystems. With
the help of molecular dynamics methods, they performed numerical
analysis of processes of hydrogen absorption by the C20, C60, C80,
C180, C240, C540 fullerenes and the C46, C167, C505 carbonic clusters
at various pressures and temperatures. The researchers managed not
only to determine the influence of these thermodynamic parameters on
the fullerenes’ hydrogen absorption ability but also to discover the
parameters at which hydrogen can be stably stored in these nanoobjects.
“The quantity of hydrogen absorbed at the temperature of 60 Kelvin
degrees and the pressure of ten megapascals achieves the 13.61 percent,
and at the temperature of liquid nitrogen boiling - 77 Kelvin degrees
- and the pressure of ten megapascals it reaches 6.6 percent”, say the
authors of the research. Utilization of carbonic clusters the resemble
fullerenes in shape is highly promising, the researchers state, as
clusters’ internal surface opens for absorption, which is not the case
with fullerenes.
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