Phase Evolution in La-Alloyed β-Ga₂O₃ Nanofibers: Experimental and DFT Simulation Insights

Area of Science:

• Materials Science
• Nanotechnology
• Solid State Chemistry

Background:

• Gallium oxide (Ga2O3) is a promising semiconductor for power electronics.
• Understanding the effects of alloying elements on Ga2O3 properties is crucial for device optimization.
• Lanthanum (La) incorporation is explored to potentially enhance Ga2O3's electrical characteristics.

Purpose of the Study:

• To synthesize La-alloyed β-Ga2O3 nanofibers using electrospinning.
• To investigate the impact of varying La concentrations on phase formation and material properties.
• To explore the potential of La alloying for improving Ga2O3-based electronic devices.

Main Methods:

• Synthesis of La-alloyed β-Ga2O3 nanofibers with 0, 1, 5, and 10 at. % La via electrospinning.
• Phase analysis to identify crystalline structures formed at different La concentrations.
• Density Functional Theory (DFT) simulations to predict properties of La-containing phases.

Main Results:

• The polycrystalline β-Ga2O3 phase remained stable at 1 at. % La, indicating it's within the solubility limit.
• Higher La concentrations (5 and 10 at. %) resulted in the formation of additional phases: La2O3, Ga3La5, La4Ga2O5, cubic La2O5, and orthorhombic LaGaO3.
• A nonoxide metallic compound, La3Ga5, was observed at higher La concentrations, confirmed by DFT to possess metallic properties.

Conclusions:

• La alloying significantly influences the phase formation in β-Ga2O3 nanofibers.
• The formation of metallic La3Ga5 suggests a pathway to enhance the electrical conductivity of Ga2O3.
• DFT simulations provide valuable insights into alloying behavior and predict potential improvements for Ga2O3 in electronic applications.