Self-Healable, High-Stability Anode for Rechargeable Magnesium Batteries Realized by Graphene-Confined Gallium Metal

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Rechargeable magnesium batteries (RMBs) offer high energy density but face challenges with anode stability and cycling life.
• Developing robust anode materials is crucial for advancing RMB technology.

Purpose of the Study:

• To develop a self-healable and high-stability anode material for rechargeable magnesium batteries.
• To investigate the performance of a core-shell structured Ga@rGO anode in RMBs.

Main Methods:

• Fabrication of a core-shell structure with gallium (Ga) confined by reduced graphene oxide (rGO).
• Characterization of the Ga@rGO anode's electrochemical performance using galvanostatic cycling.
• Evaluation of the anode's stability and self-healing properties under various current densities and temperatures.
• Application of a direct drop coating (DDC) method for material fabrication.

Main Results:

• The Ga@rGO anode achieved a specific capacity of 150 mAh g⁻¹ at 0.5 A g⁻¹ stable for 1200 cycles at room temperature.
• A specific capacity of 100 mAh g⁻¹ was maintained at an ultrahigh current of 1 A g⁻¹ for 700 cycles at 40 °C.
• The material demonstrated excellent cycling stability, high rate capability, and remarkable self-healing ability, even under ultrahigh charging currents.
• A cost-effective, simple, and environmentally friendly direct drop coating (DDC) method was employed.

Conclusions:

• The core-shell Ga@rGO anode exhibits exceptional stability, self-healing capabilities, and high performance for rechargeable magnesium batteries.
• The developed anode material and fabrication method are promising for the advancement of high-rate and long-cycle life RMBs.