Adsorption of magnesium porphyrin on Au(111)-supported graphene and hexagonal boron nitride monolayers: A first-principles study

Adsorption of porphyrins on solid surfaces plays a key role to its application in various fields. In this work, we investigate the adsorption properties of a commonly studied model metalloporphyrin, magnesium porphyrin (MgP), on bare Au(111) surface and graphene/hexagonal boron nitride (h-BN) covered Au(111) surfaces. The moir\'e structure of the graphene/Au(111) and h-BN/Au(111) heterosurfaces as a result of the lattice mismatch and its influence of the adsorption of MgP were also studied. The adsorption energies and charge transfer properties calculated at the stable adsorption configurations indicates that the inclusion of the two-dimensional (2D) materials can significantly suppress the direct interaction between the MgP molecule and the Au(111) substrate. Further analysis of the partial density of states and wave function of the frontier molecular orbitals demonstrate that the electronic structure of the MgP molecule can be well preserved, highlighting the decoupling efficiency of two types of 2D materials especially the wide band gap h-BN.