Step-guided epitaxial growth of blue phosphorene on vicinal Ag(111)

Blue phosphorene (blue-P) is a promising candidate for developing next-generation nanoelectronics devices due to its unique properties. Therefore, the controllable growth of a two-dimensional (2D) wafer-scale blue-P monolayer on substrates is a fundamental issue. However, the direct growth of blue-P on substrates currently remains a daunting challenge. In this paper, by using first-principles calculations, we propose a feasible route for fabricating blue-P via epitaxial growth. The growth mechanism of one-dimensional (1D) phosphorene chains to finite-sized blue-P clusters on Ag(111) is elucidated, and the reason why blue-P clusters cannot grow into a large-area monolayer on the Ag(111) surface is revealed. Moreover, the growth of blue-P on vicinal Ag(111) is explored and the energetic benefit of 1D zigzag blue-P nanoribbon growth along the $\mathrm{Ag}\ensuremath{\langle}110\ensuremath{\rangle}$ step edge is confirmed. More importantly, we propose that the unidirectionally orientated blue-P nanoribbons can merge into large-area blue-P nanosheets through a step-guide growth mode. The feasibility of this strategy is validated by using molecular dynamics simulations, and a series of candidate substrates is selected. This study not only provides a promising substrate for epitaxial growth of blue-P but also sheds light on the preparation of more 2D materials.