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The structures and properties of icosahedral Co 13−x Cu x (x = 0–13) nanoclusters and their interaction with pyridinic N 3 -doped graphene (PNG) nanoflake were studied using auxiliary density functional theory. First, the spin multiplicity, harmonic frequency, spin magnetic moment per atom, average bond length (ABL), vertical ionization potential (VIP), vertical electron affinity (VEA), and chemical hardness (η) of the icosahedral Co 13−x Cu x (x = 0–13) nanoclusters were investigated. Subsequently, the Co 13−x Cu x (x = 0–13) nanoclusters were supported on PNG nanoflake and their interaction energies (E int) and charge transfers were computed. The spin multiplicity and spin magnetic moment per atom decrease as the quantity of Co atoms diminishes in the Co 13−x Cu x (x = 0–13) nanoclusters revealing that the magnetic behavior is dependent on the quantity of Co atoms in the Co 13−x Cu x nanoclusters, whereas the ABL values raise as the number of Cu atoms increases in Co 13−x Cu x (x = 0–13) nanoclusters. The Co 9 Cu 4 and Co 8 Cu 5 nanoclusters present the smallest η confirming the minor electronic stabilities for these systems. On the interaction between Co 13−x Cu x (x = 0–13) nanoclusters and PNG nanoflake, charge transfer occurs from the nanoclusters to the PNG nanoflake. This study demonstrated that PNG nanoflake is an adequate material to stabilize the Co 13−x Cu x (x = 0–13) nanoclusters. • The structures and properties of Co 13−x Cu x (x = 0–13) nanoclusters were investigated. • The stability of the Co 13−x Cu x (x = 0–13) nanoclusters supported on pyridinic N 3 -doped graphene nanoflake was studied. • Spin magnetic moment per atom decrease as the quantity of Co atoms diminishes in the Co 13−x Cu x (x = 0–13) nanoclusters. • Average bond length values raise as the number of Cu atoms increases in Co 13−x Cu x (x = 0–13) nanoclusters. • The pyridinic N 3 -doped graphene nanoflake is an adequate support material. [ABSTRACT FROM AUTHOR]

A theoretical study was developed to investigate the stability, magnetic, energetic, and reactivity properties of icosahedral Pd and M@Pd 12 (M = Fe, Co, Ni, and Cu) core-shell nanoparticles supported on pyridinic N 3 -doped graphene (PNG). The investigated properties of the Pd-based nanoparticles/PNG composites are compared with those of isolated Pd and M@Pd 12 nanoparticles. All calculations were made with the auxiliary density functional theory using the generalized gradient approximation. The structural, magnetic, energetic, and reactivity properties of the M@Pd core-shell nanoparticles are modified with respect to pure Pd 13 nanoparticle. These changes in the properties are associated with the M atoms positioned in the center of the M@Pd 12 core-shell nanoparticles. On the interaction between the Pd and M@Pd 12 core-shell nanoparticles and PNG, the charge is transferred from the nanoparticles to the PNG, where the N atoms receive the major part of the charge, because of the large electronegativity of N. It is also noted an important decrease of the total magnetic moments and hardness of the Pd-based nanoparticles/PNG composites compared with the isolated nanoparticles. According to E int and hardness, PNG is a good support material because it enhances the stability and reactivity of Pd and M@Pd 12 core-shell nanoparticles supported on PNG. Description: Icosahedral M@Pd12 (M = Fe, Co, Ni, and Cu) core-shell nanoparticles supported on pyridinic N3-doped graphene. Image 1 • The structures and properties of icosahedral Pd and M@Pd 12 (M = Fe, Co, Ni, and Cu) core-shell nanoparticles were investigated. • The properties of icosahedral Pd and M@Pd 12 (M = Fe, Co, Ni, and Cu) core-shell nanoparticles supported on pyridinic N 3 -doped graphene (PNG) were studied. • The structural, magnetic, energetic, and reactivity properties of the M@Pd core-shell nanoparticles are modified with respect to pure Pd 13 nanoparticles. • The PNG is a good support material because it enhances the stability and reactivity of the Pd and M@Pd 12 core-shell nanoparticles supported on PNG. [ABSTRACT FROM AUTHOR]