A Universal Strategy Based on Bridging Microstructure Engineering and Local Electronic Structure Manipulation for...

Area of Science:

• Materials Science
• Electrochemistry
• Solid-State Chemistry

Background:

• O3-NaNi0.5Mn0.5O2 is a promising cathode material for sodium-ion batteries (SIBs) due to its high capacity.
• Practical application of these SIBs is hindered by irreversible phase transitions, poor structural stability, low operating voltage, and unstable oxygen redox reactions.

Purpose of the Study:

• To propose a universal strategy for enhancing the performance of O3-NaNi0.5Mn0.5O2 cathode materials in SIBs.
• To investigate the effects of microstructure engineering and local electronic structure manipulation on material properties.
• To address challenges like multiphase transitions, structural instability, and redox reactions.

Main Methods:

• Utilized O3-NaNi0.5Mn0.5-SnO2 as a model system for cathode material research.
• Employed a strategy bridging microstructure engineering and local electronic structure manipulation.
• Conducted density functional theory (DFT) calculations to analyze the effect of Sn substitution on electronic structure.

Main Results:

• The proposed strategy successfully modulated physical and chemical properties of the electrode materials.
• Demonstrated restraint of unfavorable multiphase transformations and improved structural stability.
• Showcased manipulation of redox potential and stabilization of anion redox reactions.
• Validated the universal strategy through Ti substitution, indicating broad applicability.

Conclusions:

• The developed strategy offers a pathway to overcome limitations in current SIB cathode materials.
• The findings provide guidance for designing advanced cathode materials for next-generation SIBs.
• The approach of combining microstructure and electronic structure manipulation is effective for enhancing electrochemical performance.