First-principles calculations of electronic and optical properties of C-doped and F, C-codoped cubic ZrO₂

Highlights: • Strong C2p–O2p/Zr4d admixtures result in a half-metallic ferromagnetism behavior. • Both 2p–2p and 2p–4d/2p–2p interactions contribute to long-range magnetic coupling. • By F and C codoping, the band gap is obviously larger than C-doped system. • Codoping of F and C induces new steep absorption peaks at lower energy region. - Abstract: First-principles calculations based on DFT + U were performed on electronic and optical properties of C-doped and F, C-codoped cubic ZrO₂. The calculations show the half-metallic ferromagnetism behaviors of both C-doped and F, C-codoped cubic ZrO₂. Both the direct 2p–2p interaction and the indirect 2p–4d/2p–2p coupling interactions can be expected to contribute to the long-range magnetic coupling. By substitutional codoping of F and C, the band gap is obviously larger than that of C-doped system, because the 2p states energies in upper valence band greatly decrease. Meanwhile, F and C codoping induces obvious increase of refractive index and also new steep absorption peaks at lower energy region ∼2.5 eV, which can be used for photo absorption applications