Transition-metal dispersion on carbon-doped boron nitride nanostructures: Applications for high-capacity hydrogen storage

Abstract

Using density-functional theory calculations, we investigated the adsorption of transition-metal (TM) atoms (TM = Sc, Ti, V, Cr, Mn, Fe, Co, and Ni) on carbon doped hexagonal boron nitride (BN) sheet and the corresponding cage (B 12 N 12 ). With carbon substitution of nitrogen, Sc, V, Cr, and Mn atoms were energetically favorable to be dispersed on the BN nanostructures without clustering or the formation of TM dimers, due to the strong binding between TM atoms and substrate, which contains the half-filled levels above the valence bands maximum. The carbon doped BN nanostructures with dispersed Sc could store up to five and six H 2 , respectively, with the average binding energy of 0.3 ∼ 0.4 eV, indicating the possibility of fabricating hydrogen storage media with high capacity. We also demonstrated that the geometrical effect is important for the hydrogen storage, leading to a modulation of the charge distributions of d levels, which dominates the binding between H 2 and TM atoms.

DFT study of adsorption behavior of NO, CO, NO2, and NH3 molecules on graphene-like BC3: A search for highly sensitive molecular sensor

“…Unlike the zero-gap semi-metal graphene, BC 3 is a semiconductor with a band gap of 0.46-0.73 eV [38][39][40][41][42][43]. It was shown that the pristine [44], Li-doped [45], polylithiated molecule-doped [46], and transition metal-doped [47][48][49] BC 3 have high potential for H 2 storage.…”

First principles guide to tune h-BN nanostructures as superior light-element-based hydrogen storage materials: role of the bond exchange spillover mechanism

“…The H 2 interaction on this medium shows a crossover between Kubas and multipole Coulomb effect depending on the ionic state of AEM and the number of adsorbed H 2 molecules. [25][26][27] For instance, carbon doped boron nitride cages are proven to have promising potential as hydrogen storage materials with a storage capacity of 7.43 wt %. The charge transfer from Be (~ 1.2 e) to nearest carbon atoms (~ 0.4 e to each neighbors) is established to be the cause of the enhanced binding strength.…”

Transition metal Ti coated porous fullerene C24B24: Potential material for hydrogen storage

“…Due to the simple van der walls dominates the binding of hydrogen molecules to the surface of pure C-based nanomaterials, the surfaces cannot efficiently store hydrogen. However, their metal decorated counterparts such as C 48 B 12 M 12 (M ¼ Fe, Co, Ni) [7], M 32 B 80 (M ¼ Ca and Sc) [8], Rh coated carbon nanotubes [9], metal decorated graphene [10], Li 9 C 60 [11] have exhibited remarkable hydrogen adsorption capacity [12]. Unfortunately, it is difficult to realize these metal decorated materials experimentally, since metal atoms tend to form clusters on the surfaces of nanostructures, and consequently the hydrogen storage capacity drops dramatically.…”

“…Therefore, the binding energy of a metal atom to the substrate should be larger than the experimental cohesive energy of the bulk metal [13]. It was suggested that alkali metals (AM) and alkaline-earth metals (AEM) can produce a homogeneous coating due to their lightweight and low cohesive energies [8,12]. The hydrogen adsorption on these structures has been demonstrated experimentally, such as Li 12 C 60 [13e15].…”