Structural Stability and Disorder Level of Moderately Reduced Paper-like Graphene Oxide Investigated with Micro-Raman...

Area of Science:

• Materials Science
• Nanotechnology
• Chemistry

Background:

• Graphene oxide (GO) is a promising material with numerous applications.
• Understanding the structural properties of GO after processing is crucial for its effective utilization.
• Annealing GO under vacuum can modify its properties, but requires careful characterization.

Purpose of the Study:

• To investigate the structural characteristics of paper-like graphene oxide (GO) after annealing.
• To analyze the disorder level and spectral features of functionalized graphene layers.
• To confirm the metastable nature of multilayer GO post-annealing.

Main Methods:

• Micro-Raman spectroscopy was employed to analyze GO samples.
• Samples were paper-like, comprising multiple functionalized graphene layers.
• Annealing was performed at moderate temperatures (≤500 °C) under vacuum (p ≃ 10^-4 mbar).

Main Results:

• The analyzed graphene oxide exhibited a noticeable, yet acceptable, level of structural disorder.
• Rarely observed spectral bands above 1650 cm^-1 were detected and their origins discussed.
• The carbon-to-oxygen (C/O) ratio remained between 2 and 3, indicating metastable multilayer GO.

Conclusions:

• The annealing process at moderate temperatures under vacuum yields graphene oxide with a manageable disorder level.
• The observed spectral features and C/O ratio confirm the metastable character of the processed GO.
• This research provides insights into the structural stability and properties of annealed graphene oxide for potential applications.