Ultrasonic Nebulization for TEM Sample Preparation on Single-Layer Graphene Grids.

Area of Science:

• Materials Science
• Nanotechnology
• Analytical Chemistry

Background:

• Traditional drop-casting for transmission electron microscopy (TEM) sample preparation can introduce drying artifacts.
• Fragile support materials, like single-layer graphene, are prone to rupture during drop-casting.
• Conventional methods lack precise control over nanoparticle deposition uniformity.

Purpose of the Study:

• To introduce and evaluate ultrasonic spray-coating as an alternative TEM sample preparation technique.
• To demonstrate the suitability of spray-coating for delicate substrates.
• To explore the potential for quantifying nanoparticle dispersion concentration using TEM imaging.

Main Methods:

• Utilizing ultrasonic nebulization for uniform droplet generation.
• Applying spray-coating to deposit nanoparticles onto TEM grids.
• Examining nanoparticle deposition patterns and artifacts using TEM.

Main Results:

• Spray-coating minimizes drying artifacts compared to drop-casting.
• The technique successfully prepared samples on fragile single-layer graphene without substrate rupture.
• Nanoparticles formed clusters on the TEM grid, with size correlating to dispersion concentration.

Conclusions:

• Ultrasonic spray-coating is a superior method for preparing nanoparticle TEM samples, especially on fragile supports.
• The observed nanoparticle clustering offers a potential route for estimating dispersion concentrations.
• This technique enhances the reliability and applicability of TEM for nanoparticle analysis.