Hydrocarbon contamination in angström-scale channels

Area of Science:

• Nanotechnology
• Surface Science
• Materials Science

Background:

• Nonspecific molecular adsorption, like airborne contamination, alters material properties, especially in 2D materials.
• The impact of contamination on confined systems, such as nanochannels, leading to clogging, remains under-investigated.

Purpose of the Study:

• To systematically investigate hydrocarbon adsorption in angstrom (Å) slit channels of varying heights.
• To evaluate the clogging of Å-channels using hexane as a model hydrocarbon contaminant and helium gas flow measurements.
• To demonstrate the stability and self-cleansing capabilities of sub-2 nm nanochannels for practical applications.

Main Methods:

• Systematic investigation of hydrocarbon (hexane) adsorption in angstrom (Å) slit channels.
• Evaluation of channel clogging using helium gas flow measurements.
• Assessment of long-term storage and stability of Å-channels over three years.
• Demonstration of thermal treatment for channel decontamination and unclogging.

Main Results:

• The degree of clogging is directly related to the size difference between the nanochannels and the adsorbing hexane molecules.
• Sub-2 nm thin channels exhibit a dynamic transition of clogging and revival processes.
• Å-channels demonstrated stability for up to three years, with effective decontamination and unclogging via thermal treatment.

Conclusions:

• Nanochannel stability is crucial for reliable molecular transport and separation studies.
• Sub-2 nm thin channels possess self-cleansing properties, enabling robust platforms for nanofluidic applications.
• A method for assessing nanoporous membrane cleanliness is presented, vital for nanofluidics in sensing, separation, and energy generation.