Embedding of atoms into the nanopore sites of the C6N6 and C6N8 porous carbon nitride monolayers with tunable electronic properties

Abstract

Using first-principles calculations, we study the effect of embedding various atoms into the nanopore sites of both C₆N₆ and C₆N₈ monolayers. Our results indicate that the embedded atoms significantly affect the electronic and magnetic properties of C₆N₆ and C₆N₈ monolayers and lead to extraordinary and multifarious electronic properties, such as metallic, half-metallic, spin-glass semiconductor and dilute-magnetic semiconductor behaviour. Our results reveal that the H atom concentration dramatically affects the C₆N₆ monolayer. On increasing the H coverage, the impurity states also increase due to H atoms around the Fermi-level. C₆N₆ shows metallic character when the H atom concentration reaches 6.25%. Moreover, the effect of charge on the electronic properties of both Cr@C₆N₆ and C@C₆N₈ is also studied. Cr@C₆N₆ is a ferromagnetic metal with a magnetic moment of 2.40 μ_B, and when 0.2 electrons are added and removed, it remains a ferromagnetic metal with a magnetic moment of 2.57 and 2.77 μ_B, respectively. Interestingly, one can observe a semi-metal, in which the VBM and CBM in both spin channels touch each other near the Fermi-level. C@C₆N₈ is a semiconductor with a nontrivial band gap. When 0.2 electrons are removed, it remains metallic, and under excess electronic charge, it exhibits half-metallic behaviour.