Rice University scientists have devised a solid-state supercapacitor using carbon nanotube bundles.
The versatile energy storage assures to couple the superior properties of quick-charging capacitors and high-energy batteries. It can be used in on-chip nanocircuitry to whole power plants and can be totally incorporated into the production of devices.
Conventional Electric double-layer capacitors (EDLCs) or supercapacitors depend on gel-like or liquid electrolytes that are vulnerable under extreme cold or hot conditions, while Rice University’s supercapacitor replaces electrolytes completely with a solid, nanoscale coat of oxide dielectric material.
The research team led by Robert Hauge developed an array of 15-20 nm single-walled carbon nanotube bundles with a length of up to 50 µm. The array of carbon nanotube bundles was then shifted to a copper electrode having thin layers of titanium and gold to assist electrical stability and adhesion.
The conductive properties of the nanotube bundles, which are the primary electrodes, were improved subsequent to the doping with sulfuric acid. The doped nanotube bundles were then coated with thin coats of aluminum oxide, the dielectric layer, and aluminum-doped zinc oxide, the counterelectrode using a method called atomic layer deposition. The circuit was completed by a top electrode of silver paint.
Hauge stated that the team’s supercapacitor is stable and expandable. All types of solid-state solutions for energy storage will be deeply incorporated into numerous next-generation devices such as bio-implants, flexible displays, numerous varieties of sensors and all kinds of electronic applications that will gain from the quick charge and discharge rates, he said.