ABSTRACT:In spite of the significant progress
in the design and modification of materials for
specific applications like hydrogen storage,
there are still problems to achieve the desired
levels of storage. Many MOFs have been
designed and have also been synthesized but
they are still not suitable enough or can meet the
DOE standards due to moisture sensitive nature
and the possibility of stability under other
operating parameters
Hydrogen as fuel
Lower heating value 33.3
kWh/g= 123 MJ/kg (11.1kWh/g
gasoline)
8 MJ/L where as for gasoline 32 MJ/L
2017 DOE target 5.5wt% = 40g/L
volumetric capacity
wide range of Hydrogen storage materials
metal hydrides
complex hydrides
chemical hydrides
carbohydrates
clathrates
inorganic nanotutes
organic materisls
MOFs
carbon materials
Liquid density 70.8 kg/m3 at NTP
Physisorption methods
on board reversible hydrides
(interstitial, covalent metal hydrides,
amides and borohydrides
off board regenerable hydrides
( hydrocarbons, ammonia borane,
alane)
The highest 99.5 mg/g at 56 bar
and 77 K
164 mg/g at 77K 70 bar (176mg /g
highest reported so far)
symbolic many metal framework of
Zn(II), Cu(II) Mn(III),
Cr(III),La(III)
Design and synthesis of metal organic
frameworks for hydrogen storage
In high boiling solvents like DMF, DEF (80-1300 C)
solvo-thermal,
solubility
solvent-ligand exchange kinetics,
rate of crystallization
carboxylic acids, hetero-cycles containing
nitrogen
Where are we now?
To meet DOE standards still a long way
to go
New MOF with large surface area, pore
volume, open metal sites, embedded
metal catalysts facilitating hydrogen
spill over have to be designed.
ABSTRACT:In spite of the significant
progress in the design and modification of
materials for specific applications like
hydrogen storage, there are still problems
to achieve the desired levels of storage.
Many MOFs have been designed and have
also been synthesized but they are still not
suitable enough or can meet the DOE
standards due to moisture sensitive nature
and the possibility of stability under other
operating parameters