MEMS Seminar

"Not Just Graphene - the Wonderful World of Carbon (and related) Nanomaterials", Dr. Yuri Gogotsi, Professor, Dept. of Materials Science and Engineering, Drexel University
Wednesday, November 5, 2014 - 11:30am
125 Hudson Hall

Carbon, with its variety of allotropes and forms, is the most versatile material and virtually any combination of mechanical, optical, electrical or chemical properties can be achieved by controlling its structure and surface chemistry. While graphite, carbon fibers, glassy carbon, activated carbons, carbon black, and diamond are widely used nowadays, fullerenes (also polymerized, endohedral and exohedral fullerides), carbon onions (multi-shell fullerenes), nanotubes (dozens of varieties), whiskers, nanofibers, cones, nanohorns, nanodiamonds and other nanoscale carbons have been attracting much attention in the past 20-30 years. Graphene is the latest example and is the most widely researched one now. There are already thousands of carbon nanomaterials to choose from. And we need different materials to meet a variety of performance requirements. It will be shown on an example of supercapacitor electrodes that 0D and 1D nanoparticles, such as onions and nanotubes, deliver very high power due to fast ion sorption/desorption on their outer surfaces. 2D graphene offers higher charge-discharge rates compared to porous carbons and high volumetric energy density. 3D porous activated, carbide-derived and templated carbon networks, having a high surface area and porosity in the Ångrtöms or nanometers range, can provide high energy density if the pore size is matched with the electrolyte ion size. Finally, carbon-based nanostructures further expand the range of available to us nanomaterials - recently discovered 2D transition metal carbides (MXenes) have already grown into a family with a dozen of members in less than 3 year and they can challenge graphene in some applications.