Single-Layered Hittorf’s Phosphorus: A Wide-Bandgap High Mobility 2D Material

Abstract

We propose here a two-dimensional material based on a single layer of violet or Hittorf's phosphorus. Using first-principles density functional theory, we find it to be energetically very stable, comparable to other previously proposed single-layered phosphorus structures. It requires only a small energetic cost of approximately 0.04 eV/atom to be created from its bulk structure, Hittorf's phosphorus, or a binding energy of 0.3-0.4 J/m(2) per layer, suggesting the possibility of exfoliation in experiments. We find single-layered Hittorf's phosphorus to be a wide band gap semiconductor with a direct band gap of approximately 2.5 eV, and our calculations show it is expected to have a high and highly anisotropic hole mobility with an upper bound lying between 3000-7000 cm(2) V(-1) s(-1). These combined properties make single-layered Hittorf's phosphorus a very good candidate for future applications in a wide variety of technologies, in particular for high frequency electronics, and optoelectronic devices operating in the low wavelength blue color range.

Allotropes of Phosphorus with Remarkable Stability and Intrinsic Piezoelectricity

“…1 (a). It is structurally very similar to the fundamental structure-units in violet phosphorus and red phosphorus [37,56,57]. Our calculated results show that it is of about 44 meV/atom higher in energy than the α-P. And it is more favorable than most of the previously proposed 2D phosphorene allotropes.…”

“…Blue phosphorene (β-P), another 2D phosphorus allotrope, was firstly proposed by Zhu et al based on firstprinciples calculations [27] in 2014 and recently synthesized by Zhang et al through epitaxial growth method [28]. The progress in synthesis of 2D phosphorus materials [29][30][31] has stimulated significant interests in exploring new 2D phosphorus materials [32][33][34][35][36][37][38][39][40][41] and related heterostructures [42][43][44]. Many new 2D allotropes of phosphorus have been proposed.…”

“…Many new 2D allotropes of phosphorus have been proposed. For example, the atomically-thin layers of γ-P [32], δ-P [32], θ 0 -P [33] and red phosphorene [34], the diatomically-thin layers η-P [35], θ-P [35] and their transformations [36] (G1, G2, B1, B2 and B3) with pentagons, the multi-atomically-thin layer of Hittorfene [37], as well as the porous phosphorene allotropes were previously proposed [38,39] through the topological modeling method. However, none of these 2D phosphorus allotropes were reported as piezoelectric materials due to their centrosymmetric crystalline structures.…”

Prediction of Green Phosphorus with Tunable Direct Band Gap and High Mobility

“…Unlike black phosphorus, blue phosphorus displays the indirect band gaps, regardless of the number of atomic layers. Other 2D structures such as γ-, δ-, ε-, ζ-, η-, θ-, and ψ-phosphorene were later suggested based on theoretical calculations [14][15][16][17][18]. Recently, blue phosphorene has been successfully synthesized on the Au(111) substrate by molecular beam epitaxy [19].…”

Interlayer Bond Formation in Black Phosphorus at High Pressure

“…Synchrotron X-ray diffraction showed the persistence of two previously unreported peaks related to the A7 structure in the pressure range of the simple-cubic phase.T he Rietveld refinement of the data demonstrates the occurrence of atwo-step mechanism for the A7 to simple-cubic phase transition, indicating the existence of an intermediate pseudo simple-cubic structure.From ac hemical point of view this study represents ad eep insight on the mechanism of interlayer bond formation during the transformation from the layered A7 to the non-layered simple-cubic phase of phosphorus,o pening new perspectives for the design, synthesis and stabilization of phosphorene-based systems.A ss uperconductivity is concerned, anew experimental evidence to explain the anomalous pressure behavior of T c in phosphorus below 30 GPaisprovided.The current renaissance [1] of black phosphorus (bP), first obtained under high pressure by Bridgman in 1914, [2] is intimately related to the recent synthesis of phosphorene, [3,4] a2 Dc orrugated monoatomic layer of P, where each atom is single-bonded to 3n earest neighbors.T he advent of phosphorene [5][6][7][8][9][10] has indeed dramatically raised the interest of the scientific community about bP,w hose crystalline structure is actually made by the periodic stacking of phosphorene layers, in as imilar way as graphene is related to graphite,a nd the layered phases of this element currently represent an extremely active research topic [11,12] (see the Supporting Information, SI-1).At the moment crystalline bP,which is typically obtained from amorphous red phosphorus at high temperature and/or high pressure, [13,14] is the starting material for the synthesis of phosphorene,either by liquid or mechanical exfoliation. The layered semiconducting orthorhombic bP (A17, Cmce, Z = 8) [15,16] is the thermodynamically stable allotrope of the element at ambient conditions (Figure 1).…”