Molecular layer deposition of Li-ion conducting "Lithicone" solid electrolytes

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Development of advanced materials for energy storage is crucial.
• Molecular Layer Deposition (MLD) offers precise control over thin film fabrication.
• Lithium-ion batteries require efficient and stable solid-state electrolytes.

Purpose of the Study:

• To fabricate and characterize novel lithium-containing (
• lithicone
• ) thin films using MLD.
• To investigate the ionic conductivity and potential of these films for battery applications.

Main Methods:

• Fabrication of lithicone thin films via MLD using lithium tert-butoxide and ethylene glycol.
• Characterization of film stoichiometry and bonding using X-ray photoelectron spectroscopy.
• Measurement of ionic conductivity and activation energy using electrochemical impedance spectroscopy.

Main Results:

• Lithicone films with stoichiometry Li1.5C2O1.8 were successfully synthesized.
• C-O-Li moieties were identified, with a distinct bonding environment compared to lithium carbonate or alucone.
• Annealed lithicone films exhibited room temperature ionic conductivity of 3.6-5 × 10^-8 S cm^-1 with an activation energy of ~0.6 eV.

Conclusions:

• The MLD process is a viable method for creating lithicone thin films.
• Lithicone films demonstrate promising ionic conductivity for potential use in solid-state electrolytes.
• This work opens pathways for developing hybrid inorganic-organic materials for next-generation lithium-ion batteries.