First-Principles Investigation of 2D o-Al₂C₂ Monolayer: A High-Performance Anode for Li/Na-Ion Batteries.

Area of Science:

• Materials Science
• Electrochemistry
• Computational Chemistry

Background:

• Development of advanced anode materials is crucial for next-generation high-performance rechargeable batteries.
• Current limitations in battery technology necessitate exploration beyond conventional anode materials like graphite.

Purpose of the Study:

• To investigate the potential of a 2D o-Al2C2 monolayer as a novel anode material for lithium-ion and sodium-ion batteries.
• To evaluate the electrochemical performance and stability of the o-Al2C2 monolayer using theoretical methods.

Main Methods:

• Density Functional Theory (DFT) investigations.
• Ab initio molecular dynamics (AIMD) simulations to assess structural integrity and stability.
• Calculation of key electrochemical properties including specific capacity, open circuit voltage, and diffusion barriers.

Main Results:

• The o-Al2C2 monolayer exhibits excellent structural stability with a cohesive energy of -5.30 eV atom⁻¹.
• Exceptional theoretical specific capacities of 3780.42 mAh g⁻¹ for Li and 3436.75 mAh g⁻¹ for Na.
• Favorable diffusion barriers (0.62 eV for Li, 0.31 eV for Na) and optimal open circuit voltages (0.81 V for Li, 0.67 V for Na).

Conclusions:

• The o-Al2C2 monolayer demonstrates significantly superior electrochemical performance compared to graphite and other 2D anode materials.
• Its remarkable stability and high capacity make it a highly promising candidate for future lithium-ion and sodium-ion battery applications.
• The study suggests strong potential for experimental validation of o-Al2C2 in energy storage systems.