Graphene device for energy recovery in cars

Known as a ‘ballistic rectifier’, the nano-electronic device has the potential to improve energy efficiency, using the recaptured heat to power things such as air conditioning, or top up a car’s battery. Key to the rectifier’s performance is graphene’s exceptionally high electron mobility, a property which determines how fast an electron can travel in a material and how fast electronic devices can operate. The electron mobility of the ballistic rectifier enables high conversion efficiency from an alternating current to a direct current.  

“The working principle of the ballistic rectifier means that it does not require any band gap,” said Manchester’s Prof Aimin Song, one of the research leads and the inventor of the device. “Meanwhile, it has a single-layered planar device structure which is perfect to take advantage of the high electron-mobility to achieve an extremely high operating speed.”

“Unlike conventional rectifiers or diodes, the ballistic rectifier does not have any threshold voltage either, making it perfect for energy harvest as well as microwave/infrared detection.”