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Indian Journal of Chemistry -Section A (IJC-A) >
IJC-A Vol.51A [2012] >
IJC-A Vol.51A(01-02) [January-February 2012] >
| Title: | Potential of nanocarbons and related substances as adsorbents and chemical storage materials for H2, CO2 and other gases |
| Authors: | Rao, C N R
Maitra, Urmimala
Subrahmanyam, K S
Gopalakrishnan, K
Kumar, Nitesh
Kumar, Ram
Govindaraj, A |
| Keywords: | Nanocarbons
Carbon nanotubes
Graphenes
Borocarbonitrides
Hydrogen storage
Hydrogen adsorption
Carbon dioxide adsorption
Methane adsorption
Halogen storage |
| Issue Date: | Jan-2012 |
| Publisher: | NISCAIR-CSIR, India |
| Abstract: | Solid materials which can adsorb and store
hydrogen, carbon dioxide and methane are gaining importance because of the
challenges faced in the energy and environment sectors. Several materials have
been examined for the adsorption and storage of hydrogen. There is a notion
that a material comprising light elements may be better for the adsorption and
storage of hydrogen. In this context, carbon nanotubes and graphene would be
expected to be suitable materials for the purpose. However, the adsorption of
hydrogen on these materials reaches maximum values up to 3 to 4 wt%, that too
under high pressure. Chemical storage of hydrogen in nanotubes by hydrogenation
goes up to ~3wt%, but reaches a much higher value of 5 wt% or more in the case
of few-layer graphenes. The sp3 carbon-hydrogen bonds formed
by the hydrogenation of graphene decompose readily on heating to ~500 ºC or on
exposure to UV or laser radiation giving out all hydrogen, making few-layer
graphenes attractive as possible hydrogen storage materials. Chlorine can be
chemically stored in few-layer graphenes in a similar manner. Adsorption of CO2
on activated charcoal is well known. Few-layer graphenes also adsorb CO2
substantially, specially at low temperatures and reach values of 45 wt% at 195
K and 0.11 MPa, and 51 wt% at 298 K and 5 MPa. Graphene analogues containing B,
C and N with the composition BxCyNz on the
other hand, adsorb CO2 up to 128 wt% at 195 K and 0.1 MPa and 64 wt%
at room temperature, making them probably some of the best materials known for
adsorption of CO2. Interestingly, these BCN materials are equally
good for the adsorption of methane and exhibit an adsorption of nearly 15 wt%
at room temperature. |
| Page(s): | 15-31 |
| CC License: |  CC Attribution-Noncommercial-No Derivative Works 2.5 India |
| ISSN: | 0975-0975(Online); 0376-4710(Print) |
| Source: | IJC-A Vol.51A(01-02) [January-February 2012]
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