Density Functional Theory Study of the Interaction of Hydrogen with Li6C60.
Hydrogen storage properties of Li-coated C60 fullerene have been studied using density functional theory within the local density as well as generalized gradient approximation. Hydrogen atoms are found to bind to Li6C60 in two distinct forms, with the first set attaching to C atoms, not linked to Li, in atomic form. Once all such C atoms are saturated with hydrogen, the second set of hydrogen atoms bind quasi-molecularly to the Li atoms, five of which remain in the exohedral and the sixth in the endohedral position. The corresponding hydrogen gravimetric density in Li6C60H40 is 5 wt %. Desorption of hydrogen takes place in succession, the ones bound quasi-molecularly desorbing at a temperature lower than the ones bound atomically. The results are compared with the recent experiment on hydrogen adsorption in Li6C60.
†Center for Applied Physics and Technology, College of Engineering, Peking University, Beijing 100871, China.|‡Physics Department, Virginia Commonwealth University, Richmond, Virginia 23284, United States.
Qian
Q
Wang
‡Physics Department, Virginia Commonwealth University, Richmond, Virginia 23284, United States.
Puru
P
Jena
fullerene; functionaliztion; hydrogen storage; lithium