Lattice Engineering to Simultaneously Control the Defect/Stacking Structures of Layered Double Hydroxide Nanosheets...

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Layered double hydroxides (LDHs) are promising materials for energy applications.
• Controlling defect structure and porosity is crucial for enhancing LDH performance.
• Existing methods for LDH modification are often complex or inefficient.

Purpose of the Study:

• To develop an effective lattice engineering method for simultaneous control of defect structure and porosity in LDHs.
• To investigate the impact of intercalant size and charge density on defect content and porosity.
• To evaluate the performance of engineered LDHs as electrocatalysts and supercapacitor electrodes.

Main Methods:

• Lattice engineering by adjusting elastic deformation and chemical interactions during nanosheet restacking.
• Systematic variation of intercalant size and charge density.
• Electrochemical characterization for oxygen evolution reaction (OER) and supercapacitor performance.
• Density functional theory (DFT) calculations to understand structure-property relationships.

Main Results:

• A defect-rich Co-Al-LDH-NO3- nanohybrid with enhanced porosity and oxygen vacancies was successfully synthesized.
• The engineered LDH exhibited excellent OER electrocatalyst performance.
• The material achieved a record specific capacitance of ~2230 F g-1 for carbon-free LDH-based electrodes.
• Correlations between defect content, stacking number, and electrochemical performance were established.

Conclusions:

• The developed lattice engineering method effectively controls defect structure and porosity in LDHs.
• Enhanced defect sites and optimized stacking structures significantly improve energy functionalities.
• This cost-effective approach offers a viable route for designing high-performance electrocatalysts and electrode materials.