Microporous carbonaceous materials incorporated with metal
(Ti, V and Zn) for hydrogen storage.
Mala Nath
a
, Asheesh Kumar
b
and Arijit Mallick
c
Department of Chemistry, Indian Institute of Technology Roorkee, Roorkee-247667, Uttarakhand,
India
a
malanfcy@iitr.ernet.in,
b
asheeshku@gmail.com,
c
arijit.chem08@gmail.com
Keywords: carbonaceous material; hydrogen storage; metal-organic compounds; X-ray diffraction;
scanning electron microscopy
Abstract. The present research work is focused on the development and characterization of light
weight microporous carbonaceous material, such as graphite (53−150 micron) incorporated with
either titanium n-butoxide, titanium diisopropoxide bis(2,4-pentanedionate), vanadium 2,4-pentane-
dionate or zinc 2,4-pentanedionate having varying wt% of the metal (2–8%) using 2-
propanol/ethanol as solvent at 40–50 °C. The calcination has been carried out at 100, 150 and 200
°C, except the samples with titanium diisopropoxide bis(2,4-pentanedionate) which are calcined at
80 °C. FESEM along with atomic absorption studies revealed that the maximum incorporation of
metals (Zn, V and Ti) in graphite has been observed with 4 wt% of zinc 2,4-pentanedionate calcined
at 100 °C, 4 wt% of vanadium 2,4-pentanedionate calcined at 100 °C, 4 wt% of titanium n-
butoxide calcined at 100 °C and 2 wt% of titanium diisopropoxide bis(2,4-pentanedionate) calcined
at 80 °C, and equilibration time of 20-24 h has been used in each case. These samples may be used
for hydrogen storage.
Introduction
In the present energy scenario of increasing energy demand, continuously depleting fossil
fuels and alarming environmental pollution, hydrogen is considered as one of the major renewable
energy sources, which is clean and environment friendly. But there are many scientific challenges to
be overcome before hydrogen can completely replace the fossil fuels. Storage of hydrogen is a
critical issue in applications for continuous power production, especially in automobile applications
[1]. On a weight basis hydrogen has nearly three times the energy content of gasoline (120 MJ/kg
for H
2
and 44 MJ/kg for gasoline). But on volume basis the situation is reversed; gaseous H
2
has
only 3 MJ of energy per litre, liquid H
2
has 8 MJ/litre of energy, whereas gasoline has 32 MJ/litre of
energy. For efficient use of hydrogen, its energy density has to be increased by suitable storage
technology. The current available technologies for on-board hydrogen storage include (i) physical
storage via compression or liquefaction, i.e. low temperature storage as liquid hydrogen, (ii)
chemical storage in reversible hydrogen carriers, (iii) reversible metal hydrides and (iv) gas-on-
solid adsorbent. Such storage mechanisms are impediments to vehicular use of hydrogen fuel, since
high pressure and cryogenic storage technology are impractical for vehicular use. All the first three
methods suffer from the drawbacks of high cost, safety and weight. The fourth option, hydrogen
adsorption in porous carbonaceous materials such as activated carbon/charcoal has attracted many
researchers in this field because of many advantages over the other three methods. Carbonaceous
materials are chemically stable and have high thermal/electric conductivity, good strength and
elasticity. In 21
st
century, carbon materials will be focused as one of promising materials for
hydrogen storage. The surface of carbon have high energy and density so it is easy to modify for
introducing some hydrogen-friendly functional groups and the porosity of carbonaceous materials
can also be advantageous in hydrogen storage. Hydrogen storage is a major research focus for
material scientists and chemists [2-5].
Various hydrogen storage materials have been used, viz. metal hydrides [6-9], formic acid
[10], carbon nanotubes [11-13], carbonite substances [14], MOFs [15,16], and activated carbon [1,
17]. A lot of interest is created for hydrogen storage carbonaceous materials because of their
Materials Science Forum Vol 755 (2013) pp 111-117 Online: 2013-04-24
© (2013) Trans Tech Publications, Switzerland
doi:10.4028/www.scientific.net/MSF.755.111
All rights reserved. No part of contents of this paper may be reproduced or transmitted in any form or by any means without the written permission of Trans
Tech Publications, www.ttp.net. (ID: 103.21.127.76, Indian Institute of Technology Bombay, Powai, Mumbai, India-10/06/15,20:06:39)