Semiconducting character of LaN: Magnitude of the bandgap and origin of the electrical conductivity

Lanthanum nitride (LaN) has attracted research interest in catalysis due to its ability activate the triple bonds of N$_2$ molecules, enabling efficient and cost-effective synthesis ammonia from gas. While exciting progress been made use LaN functional applications, electronic character (metallic, semi-metallic, or semiconducting) magnitude band gap have so far not conclusively determined. Here, we investigate properties with hybrid density theory calculations. In contrast previous claims that is our calculations show a direct-band-gap semiconductor band-gap value 0.62 eV at X point Brillouin zone. The dispersive bands near edges leads light electron hole effective masses, making promising for optoelectronic applications. Our also reveal nitrogen vacancies substitutional oxygen atoms are two unintentional shallow donors low formation energies can explain origin previously reported electrical conductivity. clarify semiconducting nature candidate defects likely responsible measured