A Reversible Six-Electron Transfer Cathode for Advanced Aqueous Zinc Batteries

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Aqueous zinc batteries are crucial for future high-energy storage.
• Efficient Zn2+ storage requires significant electron transfer.
• Developing advanced cathode materials is essential for battery performance.

Purpose of the Study:

• To investigate the six-electron transfer electrochemistry of nano-sized TeO2/C (n-TeO2/C) for aqueous zinc batteries.
• To understand the reaction mechanism and optimize cathode performance.
• To reveal the proton-dependent nature of the electrochemical reactions.

Main Methods:

• Synthesis of nano-sized TeO2/C (n-TeO2/C) composite cathode.
• Electrochemical characterization including cycling performance and capacity measurements.
• Ex situ and in situ techniques to elucidate the reaction mechanism.

Main Results:

• The n-TeO2/C cathode demonstrated a reversible six-electron transfer.
• Achieved a superior reversible capacity exceeding 800 mAh/g at 0.1 A/g.
• Stable cycling performance was observed.
• The reaction mechanism was revealed to be proton-dependent, involving a three-phase conversion.

Conclusions:

• The n-TeO2/C cathode facilitates efficient Zn2+ storage through a reversible six-electron transfer.
• The integrated conductive nanostructure and proton-rich environment enhance electrochemical kinetics and thermodynamics.
• Understanding the proton-dependent mechanism is key to designing high-performance aqueous zinc batteries.