Ultrathin Amorphous Boron Nitride Films and Their Functional Integration in Lithium Metal Anodes.

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Ultrathin amorphous materials offer potential alternatives to 2D crystalline materials but require further investigation.
• Amorphous boron nitride (aBN) is noted for its low dielectric constant and ease of manufacturing compared to hexagonal boron nitride.
• Understanding the properties and applications of amorphous materials is crucial for advancing technology.

Purpose of the Study:

• To demonstrate wafer-scale synthesis of uniform ultrathin amorphous boron nitride (aBN) films.
• To explore the potential of aBN as an interfacial layer for lithium metal anodes.
• To evaluate the performance of aBN in lithium-sulfur (Li-S) battery pouch cells.

Main Methods:

• Wafer-scale deposition of ultrathin aBN films using capacitively coupled plasma-chemical vapor deposition (CCP-CVD) at 400 °C.
• Characterization of aBN film uniformity and composition.
• Fabrication and testing of lithium-sulfur battery pouch cells with aBN-modified copper current collectors.

Main Results:

• Achieved wafer-scale growth of ultrathin aBN films with excellent thickness and composition uniformity.
• Demonstrated aBN's effectiveness as an interfacial layer, suppressing dendrite formation and corrosion on Li anodes.
• aBN-modified Cu current collectors in Li-S pouch cells exhibited significantly improved cycling stability and capacity retention (0.062% decay/cycle vs. 0.44% for pristine Cu).

Conclusions:

• Amorphous boron nitride (aBN) can be synthesized uniformly at scale using CCP-CVD.
• aBN serves as a high-performance interfacial layer for lithium metal anodes, enhancing reversibility and stability.
• aBN is a promising material for next-generation energy storage devices, particularly lithium metal batteries.