Multivalency-Driven Formation of Te-Based Monolayer Materials: A Combined First-Principles and Experimental study

Area of Science:

• Materials Science
• Condensed Matter Physics
• Nanotechnology

Background:

• The field of two-dimensional (2D) materials is rapidly expanding.
• New materials with unique properties are crucial for fundamental and practical applications.

Purpose of the Study:

• To predict and characterize a new class of 2D materials based on tellurium (Te).
• To explore the structural, electronic, and formation properties of these novel tellurium monolayers.

Main Methods:

• First-principles density functional theory (DFT) calculations.
• Particle-swarm optimization (PSO) for structural prediction.
• Analysis of electronic band structure and charge transport properties.

Main Results:

• Prediction of stable (α-Te) and metastable (β-Te, γ-Te) tellurene structures.
• Identification of a formation mechanism linked to the multivalent nature of tellurium.
• Demonstration of high electron and hole mobilities in α-Te and β-Te phases, exceeding those of MoS2.
• Preliminary experimental evidence for Te layering on highly oriented pyrolytic graphite (HOPG) substrates.

Conclusions:

• Tellurene represents a new family of 2D materials derived from group-VI elements.
• The multivalent nature of Te is key to forming these layered structures.
• Tellurene holds promise for future electronic and optoelectronic applications due to its superior charge transport properties.