Probing Surface-Mediated Electronic Coupling in Flat Hexagonal Phosphorus Nanostructures and Monolayer on Au(111).

Due to its diverse allotropes and intriguing properties, 2D phosphorus, also known as phosphorene, is a material of great interest. Here, the successful growth of flat hexagonal 2D phosphorus on Au(111) is reported. Starting from phosphorus linear chains at low coverage, a porous network and finally an extended 2D flat hexagonal (HexP) layer while increasing phosphorus deposition is formed. Using scanning tunneling microscopy/spectroscopy combined with ab initio calculations, the structure and electronic properties of the as-grown phosphorus structures are followed. The progressive formation of a phosphorus electronic band in the conduction band region is followed. More strikingly, a partial flatband that appears only on the HexP phase characterized by a sharp peak in the electronic spectrum is observed. These bands arise from the hybridization of phosphorus and gold atoms. This novel phosphorus-based structure exhibits remarkable electronic properties due to gold mediated phosphorus-phosphorus electronic coupling. This work paves the way for new interface material developments with attractive electronic properties.