Hydrogen is seen as a highly promising sustainable energy source for the future, especially in
applications like transportation. However, the challenge lies in finding efficient materials for its
storage, particularly for vehicle fuel. Nanocones have emerged as a potential storage material for
hydrogen. In this research, Using Density Functional Theory (DFT), hydrogen adsorption on Nidoped
carbon nanocones (Ni-CNCs) and carbon nanocone sheets (Ni-CNCSs) with inclination
angle 120° was examined. The functionalized Ni atom is found to be adsorbed on CNC and
CNCS with an adsorption energy of -4.04 and -6.365 eV, respectively. The Ni- functionalized
CNC and CNCS bind up to five and three molecules of hydrogen respectively. Where the
adsorption energy of the complexes nH2-Ni-CNC (n=3:5) is -0.573, -0.428 and -0.343 eV,
respectively and nH2-Ni-CNCS (n =2,3) is -0.478 and -0.210 eV, respectively. All of them are
inside the Department of Energy domain (-0.2 to -0.6 eV). Gravimetric capabilities are estimated
to be 5.05 wt% for CNC and 3.97 wt% for CNCS.