Superconductivity and high hardness in scandium-borides under pressure

Area of Science:

• Materials Science
• Condensed Matter Physics
• Solid-State Chemistry

Background:

• Transition-metal borides are of significant interest for their superconducting and superhard properties.
• Scandium-boron binary system remains underexplored for novel material discovery.

Purpose of the Study:

• To theoretically investigate the scandium-boron binary system.
• To predict new superconducting and superhard scandium-boride compounds.
• To identify materials with potential for industrial applications.

Main Methods:

• First-principles density functional theory calculations.
• High-throughput structural search methodology.
• Prediction of superconducting transition temperatures (Tc) and Vickers hardness.

Main Results:

• Six superconducting scandium-borides were predicted.
• Scandium boride 14 (ScB14) exhibits the highest predicted superconducting transition temperature (Tc = 12.3 K) and a Vickers hardness of 12.6 GPa.
• Scandium boride 4 (ScB4) shows a Tc of 3.6 K and a high Vickers hardness of 25.5 GPa.
• Previously synthesized Scandium boride 15 (ScB15) was confirmed to be superhard.

Conclusions:

• The study enriches the phase diagram of scandium-borides.
• Identified ScB14 and ScB4 as promising candidates for superconducting and superhard applications, respectively.
• Paves the way for experimental validation and industrial utilization of novel scandium-borides.