PORTLAND, Ore.—Scientists have discovered a way to genetically engineer a living virus to be piezoelectric, enabling self-assembling arrays of them to produce enough electricity to power small electronic devices. In their demonstration prototype, a button backed with a virus array generated enough electricity to illuminate an LCD display.
Researchers at the U.S. Department of Energy's Lawrence Berkeley National Laboratories hope to extend their discovery by growing nanoscale arrays of piezoelectric viruses in sheets that generate enough energy to power mobile devices from normal body motions, such as walking, without the need for batteries.
Each virus—technically a
bacteriophage—measures just 880 nanometers long by 6.6 nanometers in diameter and is coated with electrically charged proteins that make them piezoelectric. Negatively charged amino acids are then added to one end to make an electrical pole there that boosts the voltage potential enough, when deformed, to power electronic circuits. In practice, stacks of 20 layers of the virus impregnated material were needed to generate enough current to power devices. Gold-plated electrodes, with the virus impregnated sheets in between, created enough energy to power the LCD display from one square centimeter of piezoelectric material—producing about six nanoamperes at 400 millivolts.
Genetically engineered virus has electrical poles at each end that generate a voltage potential when deformed.
Source: Lawrence Berkeley National Labs