Revealing the CO₂ Conversion at Electrode/Electrolyte Interfaces in Li-CO₂ Batteries via Nanoscale Visualization...

Area of Science:

• Electrochemistry
• Materials Science
• Nanotechnology

Background:

• Lithium-carbon dioxide (Li-CO2) batteries offer dual functionality for carbon capture and energy storage.
• Understanding nanoscale interfacial processes is crucial for optimizing Li-CO2 battery performance.
• Current knowledge of electrode/electrolyte/CO2 interactions at the nanoscale is limited.

Purpose of the Study:

• To directly observe nanoscale CO2 conversion processes in Li-CO2 batteries.
• To investigate the effect of laser irradiation on interfacial reactions and battery performance.
• To elucidate the mechanistic insights into interfacial evolution and CO2 conversion pathways.

Main Methods:

• In situ atomic force microscopy (AFM) for nanoscale observation.
• Laser confocal microscopy-differential interference contrast (LSCM-DIC) for real-time monitoring.
• In situ Raman spectroscopy to analyze reaction intermediates.

Main Results:

• Observed 3D progressive growth and decomposition of Li2CO3/C deposits during discharge/recharge.
• Identified laser irradiation (405 nm) inducing rapid flake deposition and interface-limited decomposition.
• Discovered laser-induced formation of poorly soluble Li2C2O4 intermediates affecting Li2CO3/C pathways and capacity degradation.

Conclusions:

• Direct nanoscale observation provides mechanistic insights into Li-CO2 battery interfacial evolution.
• Laser irradiation can tune CO2 conversion pathways, impacting battery performance and degradation.
• Findings inspire strategies for monitoring and controlling interfacial reactions in electrochemical devices.