Phosphorene and Black Phosphorus: The ³¹P NMR View

Abstract

This work aims at characterizing for the first time the 31 P spin interactions determining the Nuclear Magnetic Resonance (NMR) properties of solid black phosphorus (bP) and of its few-layer exfoliated (fl-bP) form. Indeed, the knowledge of these properties is still very poor, in spite of the great interest received by this layered phosphorus allotrope and its exfoliated 2D form, phosphorene. By combining Density Functional Theory (DFT) calculations and Solid State NMR experiments on suspensions of fl-bP nanoflakes and on solid black phosphorus, it has been possible to characterize the 31 P homonuclear dipolar and chemical shift interactions, identifying the network of 31 P nuclei more strongly dipolarly coupled and highlighting two kinds of magnetically non-equivalent 31 P nuclei. These results add an important missing piece of information to the fundamental chemico-physical knowledge of bP and support future extensive applications of NMR spectroscopy to the characterization of phosphorene-based materials.

Recent Advances in Chemical Functionalization of 2D Black Phosphorous Nanosheets

“…This will rely very much on the development of advanced microscopic characterization techniques such as HRTEM, AFM, or scanning tunneling microscope, in order to be able to monitor the reactions in real time (in situ) and to “see” the true chemical structures of the functional units attached onto BPNSs. Additional techniques such as solid NMR or 2D NMR or MS can be also employed to determine the chemical structures or to probe the interactions between functional units and BPNSs . Further support may come from theoretical calculations such as DFT, which will help to predict the chemistry, process, and mechanism .…”

Recent advances in computational 31P NMR: Part 1. Chemical shifts

“…A special attention should be given to a number of papers dealing with the studies and discussion of pure solid‐state effects exemplified with the most recent contributions together with some older salient publications …”

“…As an example, in the most recent publication Martini et al . combined DFT calculation with the solid‐state 31 P NMR experiment on the suspensions of nanoflakes and the solid black phosphorus, the latter shown in Figure .…”

“…The layered crystal structure of the solid black phosphorus. Reproduced from Martini, et al with the permission of the American Chemical Society …”

Chemistry of Phosphorene: Synthesis, Functionalization and Biomedical Applications in an Update Review

“…An interesting paper by Borsacchi et al identified and quantified the 31 P nuclear spin interactions determining the Nuclear Magnetic Resonance (NMR) properties of phosphorene and solid BP [18]. First, they acquired 31 P Magic Angle Spin (MAS) NMR spectra of samples of phosphorene of different nanoflake size and suspended in different solvents: dimethylsulfoxide (DMSO), tetrahydrofuran (THF), or methanol.…”