Low-dimensional functional networks of cage-like B40 with effective transition-metal intercalations

Abstract

As the first all-boron fullerene observed in experiments, cage-like borospherene B₄₀ has attracted considerable attention in recent years. However, B₄₀ has been proved to be chemically reactive and tends to coalesce with one another via the formation of covalent bonds. We explore herein the possibility of low-dimensional functional networks of B₄₀ with effective transition-metal intercalations. We find that the four equivalent B₇ heptagons on the waist of each B₄₀ can serve as effective ligands to coordinate various transition metal centers in exohedral motifs. The intercalated metal atoms entail these networks with a variety of intriguing properties. The two-dimensional (2D) Cr₂B₄₀ network is a ferromagnetic metal while the 2D Zn₂B₄₀ network becomes semiconducting. In contrast, other 2D M₂B₄₀ (M = Sc, Ti, V, Mn, Fe, Co, Ni and Cu) networks and 1D CrB₄₀ belong to nonmagnetic metals. The 3D Cr₃B₄₀ network is a magnetic metal. This work presents the viable possibility of assembling M_n&B₄₀ metalloborospherenes into stable functional nanomaterials via effective transition-metal intercalations with potential applications in electronic and spintronic devices.