Lithiophilic Reduced Graphene Oxide/Carbonized Zeolite Imidazolate Framework-8 Composite Host for Stable Li Metal...

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Lithium (Li) metal anodes offer high energy density but suffer from dendrite growth and volume changes, hindering commercialization.
• Developing stable host materials is crucial for enabling safe and efficient lithium metal batteries.
• Existing strategies often face challenges in controlling lithium deposition and maintaining structural integrity.

Purpose of the Study:

• To propose and evaluate reduced graphene oxide (rGO) and carbonized zeolite imidazolate framework-8 (C-ZIF-8) composites as lithiophilic host materials for lithium metal anodes.
• To investigate the structural, chemical, and morphological properties of the rGO/C-ZIF-8 composites.
• To demonstrate the performance enhancement of lithium metal anodes using these composite hosts in symmetric and full cells.

Main Methods:

• Synthesis of rGO/C-ZIF-8 composites via redox reaction followed by carbonization.
• Characterization using X-ray diffraction (XRD), scanning electron microscopy (SEM), and X-ray photoelectron spectroscopy (XPS).
• Electrochemical testing of Li symmetric cells and LiFePO4-based full cells.

Main Results:

• The rGO/C-ZIF-8 composite exhibits favorable structural and functional properties for lithium metal hosting.
• Li symmetric cells demonstrated stable voltage profiles for over 100 hours at 1 mA cm⁻², preventing short-circuiting.
• Low Li plating/stripping overpotential (~101.5 mV) at 10 mA cm⁻² and good cyclability/rate capability in full cells were achieved.

Conclusions:

• The rGO/C-ZIF-8 composite effectively addresses the challenges of lithium metal anode instability.
• This lithiophilic host material promotes uniform lithium deposition and enhances battery performance.
• The developed composite shows significant promise for next-generation high-energy-density lithium metal batteries.