Abstract:
Hydrogen is an ecofriendly and affordable alternative for fossil fuels. Storage of hydrogen
with high hydrogen weight percentage is the prime obstacle to use it as a fuel. The
hydrogen storage capacity in Ti functionalized modified calix[4]pyrrole-benzene is
explored using density functional theory. Hydrogens are sequentially adsorbed over
functionalized Ti atoms as well as over the p complexes of acetylenic linkages and
pyrrole rings. The host stores 28 H2 with a maximum H wt% of 10.1 and sorption energies in
the range of 0.50e0.25 eV. Mechanism of the quasi-molecular adsorption is explained
through the analyses of electrostatic potential, distance parameters, and charges. Findings
of molecular dynamics, van ‘t Hoff desorption analysis, and the occupation number prove
that the host is thermally stable and stores H2 reversibly. Ti functionalized modified calix[4]
pyrrole-benzene proves to be a potential hydrogen storage candidate fulfilling the 2020
targets set by the US, DOE.
