Phosphorene and Black Phosphorus: The ³¹P NMR View

Area of Science:

• Materials Science
• Solid-State Physics
• Quantum Chemistry

Background:

• Black phosphorus (bP) is a layered allotrope of phosphorus with significant interest, particularly its 2D form, phosphorene.
• The nuclear magnetic resonance (NMR) properties and spin interactions of bP and few-layer bP (fl-bP) remain poorly understood.
• Understanding these fundamental properties is crucial for advancing phosphorene-based material applications.

Purpose of the Study:

• To characterize the 31P spin interactions governing the NMR properties of solid bP and fl-bP.
• To identify the network of strongly dipolarly coupled 31P nuclei.
• To distinguish between magnetically nonequivalent 31P nuclei in these materials.

Main Methods:

• Combined density functional theory (DFT) calculations with solid-state NMR experiments.
• Investigated both solid bP and suspensions of fl-bP nanoflakes.
• Analyzed 31P homonuclear dipolar and chemical shift interactions.

Main Results:

• Successfully characterized the 31P homonuclear dipolar and chemical shift interactions in bP and fl-bP.
• Identified specific networks of 31P nuclei exhibiting strong dipolar coupling.
• Distinguished two types of magnetically nonequivalent 31P nuclei.

Conclusions:

• This work provides essential missing information on the fundamental chemico-physical properties of bP.
• The findings support the use of NMR spectroscopy for characterizing phosphorene-based materials.
• Advances the understanding of spin interactions critical for phosphorene applications.