Growth of Quasi-Free-Standing Single-Layer Blue Phosphorus on Tellurium Monolayer Functionalized Au(111)

Abstract

Blue phosphorus, a newly proposed allotrope of phosphorus, represents a promising 2D material with predicted large tunable band gap and high charge-carrier mobility. Here, we report a simple method for the growth of quasi-free-standing single layer blue phosphorus on tellurium functionalized Au(111) by using black phosphorus as the precursor. In situ low-temperature scanning tunneling microscopy (LT-STM) measurements were used to monitor the growth of the single-layer blue phosphorus, which forms triangular structures arranged hexagonally on the tellurium layer. As revealed by in situ X-ray photoelectron spectroscopy, LT-STM measurements, and density functional theory calculation, the blue phosphorus layer weakly interacts with the underlying tellurium layer.

Electronic Properties of h‐BCN–Blue Phosphorene van der Waals Heterostructures

“…It is worth mentioning that the band gap of freestanding BlueP is significantly larger than the recently measured value 1.10 eV by scanning tunnelling spectroscopy . The notable difference stems from the immense binding energy between grown BlueP and Au(111) substrate . This strong substrate interaction can be weakened to become a vdW‐type interaction by using tellurium‐functionalized Au(111) …”

“…The notable difference stems from the immense binding energy between grown BlueP and Au(111) substrate . This strong substrate interaction can be weakened to become a vdW‐type interaction by using tellurium‐functionalized Au(111) …”

“…[27] The notable difference stems from the immenseb inding energy between grown BlueP and Au(111)s ubstrate. [28] This strong substrate interaction can be weakened to become av dW-type interaction by using tellurium-functionalized Au(111). [28] Generic vdWHs consisting of distinct materialst ypicallyp ossess built-in electric fields across the sheets caused by the electron transfer between the sheetsd ue to the differencei ne lectronegativity.…”

“…The bulk layer stacking of blue phosphorus intimately resembles graphite, in which the quasi‐monolayer form, termed blue phosphorene (BlueP), can be experimentally fabricated . As theoretically postulated, the production of single‐layer BlueP was achieved by molecular beam epitaxy on both Au(111) and tellurium‐functionalized Au(111) . The main advantages of this allotrope include the wide and layer‐dependent fundamental band gap (around 3.0–2.0 eV), and there are interesting possibilities to control the gap by external influences (e.g., external strain, electric fields and substitutional impurities of light atoms) .…”

“…[25] As theoretically postulated, the production of single-layer BlueP wasa chieved by molecular beam epitaxy on both Au(111)a nd tellurium-functionalized Au(111). [27,28] The main advantages of this allotropei nclude the wide and layerdependentf undamental band gap (around 3.0-2.0 eV), [25] and there are interesting possibilities to control the gap by external influences (e.g.,e xternals train, [25] electric fields [29] and substitutional impurities of light atoms). [30] Particularly,s ubstitutional doping by Nc an turn BlueP into ad irect-gaps emiconductor [29] and appliede lectric fields are able to initiate as emiconductorto-metal transition.…”