Fabrication of Hierarchically Structured Ultralightweight Graphene-Carbon Fiber Aerogel Networks and its Applications

Seamlessly integrating 2D-graphene (G) and 1D-carbon nanofiber (CF) with hierarchical porosity as a new carbon structure has great potential to offer improved properties for a broad range of applications yet remains largely unexplored. We have developed a scalable and green approach for fabricating hierarchical G-CF aerogels in a covalently bonded network with a density two orders of magnitude lower than previously reported graphene aerogels. We have established insights into the surface structure and chemistry of the developed material and how it depends on the process conditions such as temperature, time, and the precursor protein. Atomistic reactive molecular dynamics simulations are used to explore the assembly mechanism and structural transformations of proteins during the fabrication process. We discuss the application of such materials to desalination and water purification, notably demonstrating that the G-CF-aerogel can significantly improve upon existing materials, removing 99.99% of nano/microplastic contamination from sea water and desalinate by over 98% in seawater using gravity-based filtration, making it promising for water filtration/desalination applications.