Effect of transition metal substitution doping on the structure and magnetic properties of biphenylene

This study employed first-principles calculations to comprehensively explore the structural, electronic, and magnetic properties of transition metal-doped biphenylene networks (BPN). Initially, we optimized the most stable structures of biphenylene doped with various transition metals (Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn) and analyzed their binding energies and electronic structures in detail. The results indicate that the introduction of transition metals induces varying degrees of spin polarization. Specifically, Cr-doped BPN exhibits 100% spin polarization at the Fermi level, exhibiting half-metallicity properties. In contrast, V-doped, Mn-doped and Co-doped BPN shows incomplete spin polarization, and exhibit antiferromagnetic like properties on the C atom. Furthermore, an analysis of the energy differences between spin states and non-spin states confirmed the stability of spin states over non-spin states, providing theoretical support for the application of BPN as a new type of magnetic material. In summary, through transition metal doping, BPN exhibits promising applications, particularly in the fields of magnetic storage and magnetic sensors, highlighting significant potential.