Heterostructured Bi₂O₃@rGO Anode for Electrochemical Sodium Storage

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Bismuth oxide (Bi2O3) is a promising anode material for sodium-ion batteries due to its high theoretical capacity and abundant bismuth resources.
• However, Bi2O3 suffers from poor electronic conductivity and significant volume expansion during cycling, limiting its practical application.

Purpose of the Study:

• To address the limitations of Bi2O3 in sodium-ion batteries, this study aimed to enhance its electrochemical performance.
• The objective was to improve coulombic efficiency and cycling stability by fabricating a novel heterostructure.

Main Methods:

• A Bi2O3@reduced graphene oxide (rGO) heterostructure was synthesized using rGO as a conductive skeleton.
• The electrochemical performance of the Bi2O3@rGO heterostructure was evaluated for sodium storage in sodium-ion batteries.

Main Results:

• The Bi2O3@rGO heterostructure demonstrated a reversible capacity of 161 mAh g−1 after 100 cycles at 50 mA g−1, outperforming pure Bi2O3 (43 mAh g−1).
• Coulombic efficiency stabilized above 90% within 3 cycles, indicating improved reversibility and stability.
• The rGO skeleton provided structural support and enhanced electron transport pathways.

Conclusions:

• The Bi2O3@rGO heterostructure effectively suppresses the volume expansion and improves the electronic conductivity of Bi2O3.
• This engineered material shows high reversibility and stable cycling performance, making it a viable anode for sodium-ion batteries.