Computational study on the half-metallicity in transition metal-oxide-incorporated 2D g-C3N4 nanosheets

TL;DR

This study uses first-principles calculations to explore how transition metal-oxide incorporation affects the electronic and magnetic properties of 2D g-C3N4 nanosheets, revealing potential for spintronic applications.

Contribution

It provides a systematic analysis of the magnetic states and half-metallicity in TM-O incorporated g-C3N4 nanosheets, including Curie temperatures and charge transfer mechanisms.

Findings

Ferromagnetic for TM = Sc, Ti, V, Cr; antiferromagnetic for TM = Mn.

All ferromagnetic systems exhibit half-metallicity.

Curie temperatures range from 68 K to 203 K.

Abstract

In this study, based on the first-principles calculations, we systematically investigated the electronic and magnetic properties of the transition metal-oxide-incorporated 2D g-C3N4 nanosheet (labeled C3N4-TM-O, TM = Sc-Mn). The results suggest that the TM-O binds to g-C3N4 nanosheets strongly for all systems. We found that the 2D C3N4-TM-O framework is ferromagnetic for TM = Sc, Ti, V, Cr, while it is antiferromagnetic for TM = Mn. All the ferromagnetic systems exhibit the half-metallic property. Furthermore, Monte Carlo simulations based on the Heisenberg model suggest that the Curie temperatures (T_c) of the C3N4-TM-O (TM = Sc, Ti, V, Cr) framework are 169 K, 68 K, 203 K, and 190 K, respectively. Based on Bader charge analysis, we found that the origin of the half-metallicity at Fermi energy can be partially attributed to the transfer of electrons from TM atoms to the g-C3N4 nanosheet. In addition, we found that not only electrons but also holes can induce half-metallicity for 2D g-C3N4 nanosheets, which may help to understand the origin of half-metallicity for graphitic carbon nitride.