Transition-Metal-Decorated C2N and C2CF Monolayers for Tunable Magnetism and Spin-Polarized Metallic State.

Abstract:
The invention of graphene-based two-dimensional (2D) materials with tunable magnetism
and spin-polarized transport is important for next-generation spintronic and catalytic
applications. In this work, spin-polarized density functional theory (DFT) is used to
investigate the adsorption of 3d transition-metal (TM) atoms (Sc, Ti, V, Cr, Mn, Fe, Co, Ni)
on nitrogenated holey graphene (C2N) and its fluorinated derivative C2CF. The TM atoms
preferentially bind at pore-centered sites, forming stable complexes with adsorption energies
between −2.3 and −5.7 eV. Strong d–p hybridization between TM d states and host C/N/F p
states induces sizable magnetic moments of 0.6–3.8 μB for C2N and 0.4–3.5 μB for C2CF,
converting most systems into spin-polarized metals or half-metals. Band-structure, PDOS,
spin-density, and Bader charge analyses confirm that magnetism originates mainly from TM

d orbitals, with charge transfer from the TM atoms to the host. C2N provides stronger N-
coordinated anchoring, whereas the polar C–F environment of C2CF enhances charge transfer

and slightly localizes the magnetic moments. These results give TM embedded in C2N and
TM embedded in C2CF as promising platforms for tunable magnetism, spintronic devices,
and single-atom catalytic applications.