Prediction of a novel 2D porous boron nitride material with excellent electronic, optical and catalytic properties

Holey graphyne (HGY) is a recently synthesized two-dimensional semiconducting allotrope of carbon composed of a regular pattern of six- and eight-vertex carbon rings. In this study, based on first-principles density functional theory and molecular dynamics simulations, we predict a similar stable porous boron nitride holey graphyne-like structure that we call BN-holey-graphyne (BN-HGY). The dynamical and thermal stability of the structure at room temperature is confirmed by performing calculations of the phonon dispersion relations, and also ab initio molecular dynamics simulations. The BN-HGY structure has a wide direct band gap of 5.18 eV, which can be controllably tuned by substituting carbon, aluminum, silicon, and phosphorus atoms in place of sp and sp² hybridized boron and nitrogen atoms of BN-HGY. We have also calculated the optical properties of the HGY and BN-HGY structures for the first time and found that the optical absorption spectra of these structures span the full visible region and a wide range of the ultraviolet region. We found that the Gibbs free energy of the BN-HGY structure for the hydrogen adsorption process is very close to zero (-0.04 eV) and, therefore, the BN-HGY structure can be utilized as a potential catalyst for the HER. Therefore, we propose that the boron nitride analog of holey graphyne can be synthesized, and it has a wide range of applications in nanoelectronics, optoelectronics, spintronics, ultraviolet lasers, and solar cell devices.