Template synthesis of nanophase mesocarbon.
Templating techniques are used increasingly to create carbon materials with precisely engineered pore systems. This article presents a new templating technique that achieves simultaneous control of pore structure and molecular (crystal) structure in a single synthesis step. With the use of discotic liquid crystalline precursors, unique carbon structures can be engineered by selecting the size and geometry of the confining spaces and selecting the template material to induce edge-on or face-on orientation of the discotic precursor. Here mesophase pitch is infiltrated by capillary forces into a nanoporous glass followed by slow carbonization and NaOH etching. The resulting porous carbon material exhibits interconnected solid grains about 100 nm in size, a monodisperse pore size of 60 nm, 42% total porosity, and an abundance of edge-plane inner surfaces that reflect the favored edge-on anchoring of the mesophase precursor on glass. This new carbon form is potentially interesting for a number of important applications in which uniform large pores, active-site-rich surfaces, and easy access to interlayer spaces in nanometric grains are advantageous.
Yang
Nancy Y
NY
Sandia National Laboratories, Livermore, California, USA.
Jian
Kengqing
K
Külaots
Indrek
I
Crawford
Gregory P
GP
Hurt
Robert H
RH
D002244:Carbon / Q000737:chemistry; D003460:Crystallization / Q000379:methods*; D046911:Macromolecular Substances; D008422:Materials Testing; D008968:Molecular Conformation; D036103:Nanotechnology / Q000295:instrumentation / Q000379:methods*; D037742:Nanotubes, Carbon / Q000737:chemistry* / Q000648:ultrastructure*; D010316:Particle Size; D044367:Phase Transition; D016062:Porosity; D013499:Surface Properties
D046911:Macromolecular Substances; D037742:Nanotubes, Carbon; D002244:Carbon