Optical response and gas sequestration properties of metal cluster supported graphene nanoflakes

Abstract

The possibility of obtaining metal cluster (M3O(+), M = Li, Na, K) supported pristine, B-doped and BN-doped graphene nanoflakes (GR, BGR and BNGR, respectively) has been investigated by carrying out density functional theory (DFT) based calculations. Thermochemical analysis reveals the good stability of M3O(+)@GR/BGR/BNGR moieties. The dynamic stability of M3O(+)@GR/BGR/BNGR moieties is confirmed through an atom-centered density matrix propagation simulation at 298 K up to 500 fs. Orbital and electrostatic interactions play pivotal roles in stabilizing the metal-cluster supported graphene nanoflakes. The metal clusters lower the Fermi levels of the host nanoflakes and enable them to exhibit reasonably good optical response properties such as polarizability and static first hyperpolarizability. In particular, Na3O(+)/K3O(+)@BGR complexes exhibit very large first hyperpolarizability values at the static field limit. All the M3O(+)@BGR/BNGR moieties demonstrate broadband optical absorption encompassing the ultraviolet, visible as well as infrared domains. The metal-cluster supported graphene nanoflakes, in general, can sequestrate polar molecules, viz. CO, NO and CH3OH, in a thermodynamically more favorable way than GR, BGR and BNGR. In the adsorbed state, the CO, NO and CH3OH molecules, in general, attain an 'active' state as compared to their free counterparts.

Spirooxazine molecular switches with nonlinear optical responses as selective cation sensors

“…Larger stabilization interaction energies, E 2 , are known to cause stronger interactions between the bonds. [48][49][50][51][52] Therefore, the results suggested that Fe 2+ complexation was stronger, which was in good agreement with the reduced N/O distance between the ligand heads (from 2.825Å in uncomplexed merocyanine to 2.549Å in the Fe 2+ complex). Furthermore, the E 2 value would increase with decreasing metal center charge.…”

Effects of the Atomic Number of Alkali Atom and Pore Size of Graphyne on the Second Order Nonlinear Optical Response of Superalkali Salts of Graphynes OM3+@GYs– (M = Li, Na, and K)

“…35 This means that using superalkali OM 3 as a dopant may be a better choice. Noteworthily, the β 0 values of OM 3 + @(GDY/GTY)are much larger than those of previously reported superalkali (M 3 O + , M = Li, Na, and K) supported graphene nanoflakes (GR) (8.4×10 2 -3.1×10 3 au), 64 which indicates that the largely π-conjugated graphyne is superior to graphene in producing complexes with large β 0 values.…”

Recent Progress on the Design, Characterization, and Application of Superalkalis

“…Thereafter, further endeavors have been devoted to designing NLO molecules by doping superalkalis on different nanocages, including C 24 N 24 , Si 12 C 12 , C 20 , and B 40 . In addition, NLO materials can also be obtained by interacting superalkalis with other complexants, such as graphdiyne, hexamethylenetetramine, phenalenyl,– modified graphene, and P 4 molecules . Superalkalis can also be utilized as building blocks of alkalides,– which was first revealed by Wu and co‐workers .…”