En Route to Superhard and 1D Conductive Carbon Allotropes Via Unusual Sp 2–sp 3 Bonding Configuration

Carbon structures with sp ^2 – sp ^3 hybrid bonds were expected to exhibit both excellent mechanical and electronic properties. Here, we theoretically design several unique carbon structures, which contain unusual sp ^2 – sp ^3 hybrid bonds. We found that the introduction of sp ^2 bonding units into carbon structure with sp ^3 bonding can tune the electronic densities of state at Fermi level, especially resulting in 1D conductive channels in 3D structures. Further simulations indicate that Vickers hardness of these structures is close to diamond via the increase in sp ^3 building blocks. Our current work provides insights into the design of carbon structures with both excellent superhard and remarkably metallic properties.