Zero-Valent Nickel Stabilized in Surface-Supported Metal-Organic Chains

Area of Science:

• Surface Science
• Coordination Chemistry
• Materials Science

Background:

• Zero-valent nickel (Ni(0)) centers are highly reactive and prone to oxidation, making their stabilization in extended systems difficult.
• Controlling the coordination environment is crucial for stabilizing low-valent transition metal species.

Purpose of the Study:

• To demonstrate a novel strategy for stabilizing zero-valent nickel (Ni(0)) centers.
• To investigate the formation and electronic properties of Ni(0) within a surface-supported metal-organic framework.

Main Methods:

• Utilized surface-supported metal-organic chains formed by 9,10-dicyanoanthracene (DCA) on a Silver(100) (Ag(100)) substrate.
• Employed spectroscopic measurements to confirm the oxidation state and characterize the electronic structure of the stabilized nickel centers.

Main Results:

• Achieved stabilization of Ni(0) atoms via linear coordination confinement within a Ni-DCA motif on Ag(100).
• Spectroscopic data confirmed the formal Ni(0) oxidation state, a rare achievement in extended systems.
• Observed hybridization between Ni 3d orbitals and DCA's π-system, leading to anisotropic, one-dimensional electronic dispersion.

Conclusions:

• Linear coordination confinement is an effective strategy for stabilizing reactive, low-valent metal centers.
• Surface-supported metal-organic architectures can host atomically defined, low-valent transition metal species.
• This work opens avenues for designing novel materials with tailored electronic properties based on stabilized low-valent metals.