Polymerization driven monomer passage through monolayer chemical vapour deposition graphene

Area of Science:

• Materials Science
• Nanotechnology
• Physical Chemistry

Background:

• Graphene's potential for molecular sieving is significant.
• Experimental studies on mass transport through graphene are limited to small molecules like water and ions.
• Data on larger molecule translocation, especially monomers, is scarce.

Purpose of the Study:

• To investigate the translocation of neutral, anionic, and cationic monomers through single-layer graphene.
• To understand the influence of graphene defects on monomer transport.
• To explore the interaction dynamics between monomers and graphene defects.

Main Methods:

• Controlled radical polymerization using surface-anchored initiator monolayers separated by single-layer graphene.
• Raman spectroscopy to quantify changes in graphene defect ratios (I_D/I_G).
• Quantum molecular dynamics simulations to analyze monomer-graphene interactions.

Main Results:

• Neutral monomers translocated through native graphene defects, increasing the defect ratio from 0.09 to 0.22.
• Anionic and cationic monomers exhibited slower translocation due to chemical interactions with graphene defects.
• Anionic monomer translocation through micropatterned initiator layers resulted in the cutting of graphene sheets.

Conclusions:

• Graphene's native defects facilitate neutral monomer transport.
• Chemical interactions significantly impede charged monomer translocation.
• Monomer-graphene interactions can lead to structural modifications of the graphene sheet, highlighting potential applications and challenges in graphene-based separation technologies.