Collaborative Research: Interactions of Interlayered Nanoporous Graphene with Surrounding Water Molecules

Coating or surface engineering is ubiquitous in various industrial applications. Coatings can be applied to the surfaces of various electronic devices, such as microprocessors and organic light-emitting diode (OLED) displays, to prevent their degradation or oxidation of electronic or organic components when in contact with water molecules present in the atmosphere.

Advances in coating, in particular the incorporation of layers of nanomaterials, could enable breakthroughs in robustness and novel functionalities. While an ideal design of nanomaterials-based coating would take the form of defect-free, pore-free, and nanometer-thin layers, practical implementations may be limited due to manufacturing challenges. Therefore, it is critical to understand the correlations between nanolayer thickness, defect statistics, and the permeability of the coating.

This research aims to employ atomically thin graphene layers with controlled morphology and chemistry and their interlayer configurations to advance our understanding of the correlation between stacking configuration, defects, and permeability. New discoveries about the graphene-water interactions will guide the design for novel advanced coatings that protect electronic or organic devices from water vapor environments.

This research also aims to broaden nano-engineering education by engaging students under-represented in STEM and high school students via summer research opportunities, field trips, and symposia. In addition, several outreach activities, including interactive lectures and hands-on activities will be undertaken.

Since the performance of surface coatings is severely limited by attendant nanoscale defects and/or pores, there is a significant need for the precise control of diffusion through surface coatings. Although several previous studies have proposed a promising framework of multi-layered stacks, there are fundamental limitations in the control of nanoscale defects, three-dimensional tortuosity, and surface wettability.

To address these challenges, this research project aims to study diffusion transport through a new design of three-dimensionally, interlayered nanoporous graphene stacks. This is based on the following premises. First, nano-confined water molecules will behave differently than bulk water molecules, negatively impacting the diffusion process.

Second, precisely manufactured nanoporous graphene stacks will enable the improvement of overall diffusion rates by controlling the effective tortuosity and pore morphology with surface wettability. To attain this the PIs will employ a combination of multi-level simulation and experimental approaches to validate the multi-layer diffusion theory. The successful completion of this research project will build a new understanding about the diffusion physics based on interfacial science between graphene and surrounding water molecules.

The principal investigators plan to create virtual lab tours and sessions for high school students by presenting virtual hands-on activities. The PIs will engage underrepresented students in the research project through various campus level activities, including the California Alliance for Minority Participation (CAMP) program.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.