Researchers at NASA have developed new methods to manufacture carbon materials (e.g., nanotubes, graphene) with holes through the graphitic surface of the particles. The methods generate materials with increased accessible surface area, increased functional groups at damage sites, and improved through-surface molecular transport properties. The materials generated using these techniques are anticipated to be applicable to a variety of industries, especially energy storage (e.g. supercapacitors and batteries) and separation membranes (e.g. for gas, ions, organics, proteins, etc.).
The scalable methods allow preparation of bulk quantities of holey nanocarbons with holes ranging from a few to more than 100 nm in diameter. The first method uses metal particles as a catalyst (silver, copper, e.g.), and offers a wider range of hole diameter. The second method is free of catalysts altogether, and offers more rapid processing in a single step with minimal product work-up requirements. It does not require solvents, catalysts, flammable gases, additional chemical agents, or electrolysis. The process requires only commercially available materials and standard laboratory equipment, and is scalable. Properties that can be controlled include surface area, pore volume, mechanical properties, electrical conductivity, and thermal conductivity.