Intellectual Property Office

Non-Confidential Disclosures

“High Surface Area and Porosity Graphite”

PSU Inv. Disc. No 3319
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Keywords

Porous graphite; microporous carbon; carbon/graphite electrodes; fuel cells; lithium ion batteries; ultracapacitors

Inventors:

Christopher Burket, Ramakrishnan Rajagopalan, Henry Foley

Links:

Inventor Website

Background:

Current technologies utilized to create porous graphitic carbons have significant disadvantages. These materials can be made by impregnation of mesoporous silica templates by graphitizing carbon precursors, followed by pyrolysis and graphitization. However, carbons with nanopores less than 2 nm are unattainable by this method, thus limiting their ultimate surface area, porosity, and performance. Further, removal of the template requires treatment with highly corrosive hydrofluoric acid. In another method, transition and alkali metals catalyze graphitization of carbon. These methods require addition of metallic heteroatoms to the carbonaceous material. A third means involves exfoliation of graphite to improve its surface area and porosity. Unfortunately, intercalation with strong acids, followed by a thermal shock treatment is necessary to produce this material by this route. The present invention is a method to prepare nanoporous graphite without these disadvantages.

Invention description:

Porosity and graphitizability are two important physical parameters which makes carbon materials useful for wide range of energy applications ranging from fuel cell catalysts, to anode materials for lithium ion batteries, and electrodes for ultracapacitors. However, tunability of porosity and extent of graphitizability in carbons are mutually exclusive as the origin of porosity is directly proportional to the degree of disorder in most carbon materials. The present invention uses a non-graphitizing polymeric precursor as a source to produce nanoporous carbon by pyrolysis. Activation creates a nanoporous carbon with additional surface area and porosity. The surface area, nanopore diameter, nanopore and mesopore volume, and ratio of nanopores to mesopores can be controlled during the activation process. Nanoporous carbons with greater than 2000 m2/gm of surface area and a pore volume 1.33 cm3/gm have been generated. A majority of the pores have diameters less than 1 nm. Further treatment by a simple method surprisingly results in significant graphitization of these carbons. The carbon product is both graphitic and nanoporous with a surface area greater than 1000 m2/gm (a-NPC2000 in the Figure).

Advantages:

• Nanoporous graphite with pore diameter < 1nm and surface area >1000 m2/gm
• Simple synthesis producing a product with no heteroatomic species

Contact:

Bradley A. Swope
Sr. Technology Licensing Officer
Intellectual Property Office
113 Technology Center
The Pennsylvania State Univ.
University Park, PA 16802-7000
Phone: (814) 863-5987
Fax: (814) 865-3591
E-mail:bradswope@psu.edu