Post by williamplayer on Jan 15, 2015 13:15:02 GMT
Laser-Induced Graphene 'Super' for Electronics
An electron microscope image shows the cross section of laser-induced graphene burned into both sides of a polyimide substrate. The flexible material created at Rice University has the potential for use in electronics or for energy storage. Credit: Tour Group/Rice University
READ FULL ARTICLE: phys.org/news/2015-01-laser-induced-graphene-super-electronics.html#jCp Rice University scientists advanced their recent development of laser-induced graphene (LIG) by producing and testing stacked, three-dimensional supercapacitors, energy-storage devices that are important for portable, flexible electronics.
The Rice lab of chemist James Tour discovered last year that firing a laser at an inexpensive polymer burned off other elements and left a film of porous graphene, the much-studied atom-thick lattice of carbon. The researchers viewed the porous, conductive material as a perfect electrode for supercapacitors or electronic circuits.
To prove it, members of the Tour group have since extended their work to make vertically aligned supercapacitors with laser-induced graphene on both sides of a polymer sheet. The sections are then stacked with solid electrolytes in between for a multilayer sandwich with multiple microsupercapacitors.
The flexible stacks show excellent energy-storage capacity and power potential and can be scaled up for commercial applications. LIG can be made in air at ambient temperature, perhaps in industrial quantities through roll-to-roll processes, Tour said.
The research was reported this week in Applied Materials and Interfaces.
Capacitors use an electrostatic charge to store energy they can release quickly, to a camera's flash, for example. Unlike chemical-based rechargeable batteries, capacitors charge fast and release all their energy at once when triggered. But chemical batteries hold far more energy. Supercapacitors combine useful qualities of both - the fast charge/discharge of capacitors and high-energy capacity of batteries - into one package.
LIG supercapacitors appear able to do all that with the added benefits of flexibility and scalability. The flexibility ensures they can easily conform to varied packages - they can be rolled within a cylinder, for instance - without giving up any of the device's performance.
The Rice lab of chemist James Tour discovered last year that firing a laser at an inexpensive polymer burned off other elements and left a film of porous graphene, the much-studied atom-thick lattice of carbon. The researchers viewed the porous, conductive material as a perfect electrode for supercapacitors or electronic circuits.
To prove it, members of the Tour group have since extended their work to make vertically aligned supercapacitors with laser-induced graphene on both sides of a polymer sheet. The sections are then stacked with solid electrolytes in between for a multilayer sandwich with multiple microsupercapacitors.
The flexible stacks show excellent energy-storage capacity and power potential and can be scaled up for commercial applications. LIG can be made in air at ambient temperature, perhaps in industrial quantities through roll-to-roll processes, Tour said.
The research was reported this week in Applied Materials and Interfaces.
Capacitors use an electrostatic charge to store energy they can release quickly, to a camera's flash, for example. Unlike chemical-based rechargeable batteries, capacitors charge fast and release all their energy at once when triggered. But chemical batteries hold far more energy. Supercapacitors combine useful qualities of both - the fast charge/discharge of capacitors and high-energy capacity of batteries - into one package.
LIG supercapacitors appear able to do all that with the added benefits of flexibility and scalability. The flexibility ensures they can easily conform to varied packages - they can be rolled within a cylinder, for instance - without giving up any of the device's performance.