Kinetics-Limited Two-Step Growth of van der Waals Puckered Honeycomb Sb Monolayer

TL;DR

This paper uncovers the atomic-scale growth mechanism of puckered honeycomb Sb monolayer, revealing a kinetics-limited two-step process involving initial distorted hexagonal lattice formation followed by transformation into the puckered honeycomb structure.

Contribution

It provides the first detailed atomic-scale understanding of the growth mechanism of puckered honeycomb Sb monolayer using combined microscopy and theoretical calculations.

Findings

Growth occurs via a two-step process.

Initial formation of distorted hexagonal lattice.

Transformation into puckered honeycomb monolayer.

Abstract

Puckered honeycomb Sb monolayer, the structural analog of black phosphorene, has been recently successfully grown by means of molecular beam epitaxy. However, little is known to date about the growth mechanism for such puckered honeycomb monolayer. In this study, by using scanning tunneling microscopy in combination with first-principles density functional theory calculations, we unveil that the puckered honeycomb Sb monolayer takes a kinetics-limited two-step growth mode. As the coverage of Sb increases, the Sb atoms firstly form the distorted hexagonal lattice as the half layer, and then the distorted hexagonal half-layer transforms into the puckered honeycomb lattice as the full layer. These results provide the atomic-scale insight in understanding the growth mechanism of puckered honeycomb monolayer, and can be instructive to the direct growth of other monolayers with the same structure.