Enhanced hydrogen adsorption on Li-coated B12C6N6

Abstract

The hydrogen storage property of Li-coated BCN is investigated by density functional theory calculations. BCN is an electron deficient fullerene. Li atoms can be strongly bound to this cage by donating their valance electrons to the virtual 2p orbitals of carbon in the cluster. The binding energy (-2.90 eV) is much larger than the cohesive energy (1.63 eV) of bulk Li, and it prevents the Li atoms from aggregation. The coated Li atoms have large positive charges and the adsorbed hydrogen molecules can be moderately polarized by the Li ions. The computation shows that each Li atom coated on BCN can hold 2-3 H molecules with adsorption energies in the range of 0.21-0.24 eV/H. The BCNLi can adsorb 16 H and achieve a gravimetric hydrogen density of 8.63 wt. %. The present results indicate that alkali-metal atoms coated on electron deficient fullerenes can serve as hydrogen storage materials that can operate at ambient temperatures with high recycling storage capacity.

High‐capacity hydrogen storage on Li‐decorated B16N16

“…Jia et al found that the modification of Li atoms significantly increased the storage capacities (29.2 wt%) on the B‐N chains with the binding energy of 0.15 eV/H 2 29 . Our recent study indicated that the fullerene B 12 C 6 N 6 coated by Li atoms could achieve a high hydrogen density of 8.63 wt%, and the adsorption strength per hydrogen was in the range of 0.21–0.24 eV 30 . It was found that both B 12 N 12 and B 16 N 16 stand out as magic BN‐fullerenes and their particular stabilities were affirmed experimentally 31‐33 .…”

“…But the transition metals usually have large cohesive energies and tend to be aggregated on the substrate 17‐19 . Therefore, alkali and alkaline metal atoms are better choices for decoration because of their lightweight and small cohesive energies, which will prevent the clustering of the metal atoms 20‐30 . As the lightest metal, lithium atoms were selected for decoration on BN nanosystems in many studies.…”

“…29 Our recent study indicated that the fullerene B 12 C 6 N 6 coated by Li atoms could achieve a high hydrogen density of 8.63 wt%, and the adsorption strength per hydrogen was in the range of 0.21-0.24 eV. 30 It was found that both B 12 N 12 and B 16 N 16 stand out as magic BN-fullerenes and their particular stabilities were affirmed experimentally. [31][32][33] This article studies the structures and stability of Li-decorated B 16 N 16 and their hydrogen adsorption properties.…”

“…[17][18][19] Therefore, alkali and alkaline metal atoms are better choices for decoration because of their lightweight and small cohesive energies, which will prevent the clustering of the metal atoms. [20][21][22][23][24][25][26][27][28][29][30] As the lightest metal, lithium atoms were selected for decoration on BN nanosystems in many studies. In the work of Venkataramanan, the Li 6 B 36 N 36 cluster held 18 H 2 and the adsorption energy of each H 2 was 0.19 eV.…”

Hydrogen adsorption behavior on AXenes Na2N and K2N: a first-principles study

“…In the light of the large surface-to-volume ratio and special electronic structures, 2D materials are used to immobilize hydrogen molecules with superiority [5][6][7][8]. In general, doping and decoration are commonly used to improve the hydrogen storage properties of 2D materials, in terms of modulating the surface properties of the material and adjusting the hydrogen adsorption energy [9]. It should be pointed out that carbon-based nanomaterials, which are extensively studied as hydrogen storage systems, indicate weak binding to hydrogen molecule and thus are not suitable for hydrogen storage [10,11].…”