title: Two-Dimensional Phosphorus Oxides as Energy and Information Materials.
abstract: Phosphorene is a rising star in electronics. Recently, 2D phosphorus oxides with higher stability have been synthesized. In this study, we theoretically explored the structures and properties of 2D phosphorus oxides. We found that the structural features of Px Oy vary with the oxygen content. When the oxygen content is low, the most stable Px Oy material can be obtained by the adsorption of O atoms on phosphorene. Otherwise, stable structures are no longer based on phosphorene and will contain P-O-P motifs. We found that P4 O4 has a direct band gap (about 2.24 eV), good optical absorption, and high stability in water, so it may be suitable for photochemical water splitting. P2 O3 adopts two possible stable ferroelectric structures (P2 O3 -I and P2 O3 -II) with electric polarization perpendicular and parallel to the lateral plane, respectively, as the lowest-energy configurations, depending on the layer thickness. We propose that P2 O3 could be used in novel nanoscale multiple-state memory devices.
authors.affiliation: Key Laboratory of Computational Physical Sciences (Ministry of Education), State Key Laboratory of Surface Physics and Department of Physics, Fudan University, Shanghai, 200433, China.|Collaborative Innovation Center of Advanced Microstructures, Nanjing, 210093, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Luo
authors.affiliation: Key Laboratory of Computational Physical Sciences (Ministry of Education), State Key Laboratory of Surface Physics and Department of Physics, Fudan University, Shanghai, 200433, China. hxiang@fudan.edu.cn.|Collaborative Innovation Center of Advanced Microstructures, Nanjing, 210093, China. hxiang@fudan.edu.cn.
authors.forename: Hongjun
authors.initials: H
authors.lastname: Xiang
keywords: ab initio calculations; ferroelectricity; phosphorus oxides; photochemistry; two-dimensional materials