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nanotimes News in Brief

12-03 :: March/April 2012

Graphene Supercapacitors // Laser Scribed Graphene Supercapacitors

© Based on Material by UCLA R

esearchers from University of California, and the California NanoSystems Institute demonstrate

high-performance graphene-based electrochemical capacitors that maintain excellent electrochemical attributes under high mechanical stress. The resear- chers at UCLA have used a standard LightScribe DVD optical drive to produce such electrodes. The elec- trodes are composed of an expanded network of gra- phene that shows excellent mechanical and electrical properties as well as exceptionally high surface area.

Devices made with Laser Scribed Graphene (LSG) electrodes exhibit ultrahigh energy density values in different electrolytes while maintaining the high po- wer density and excellent cycle stability of ECs. Mo- reover, these ECs maintain excellent electrochemical attributes under high mechanical stress and thus hold promise for high power, flexible electronics.

“Our study demonstrates that our new graphene-ba- sed supercapacitors store as much charge as conven- tional batteries, but can be charged and discharged a hundred to a thousand times faster,” said Richard B. Kaner, professor of chemistry & materials science and engineering.

“Here, we present a strategy for the production of high-performance graphene-based ECs through a simple all solid-state approach that avoids the resta- cking of graphene sheets,” said Maher F. El-Kady,

Schematic showing the structure of laser scribed graphene supercapacitors. © UCLA

the lead author of the study and a graduate student in Kaner‘s lab.

El-Kady, et al.: Laser Scribing of High-Performance and Flexible Graphene-Based Electrochemical Capacitors, In: Science, March 16, 2012, Pages 1326-1330, DOI:10.1126/ science.1216744:

http://dx.doi.org/10.1126/science.1216744 http://www1.cnsi.ucla.edu