42
nanotimes News in Brief
12-04 :: April/May 2012
Energy Generation // Scientists Generate Electricity from Viruses
S
cientists from the Lawrence Berkeley National Laboratory (Berkeley Lab) have developed a
way to generate power using harmless viruses that convert mechanical energy into electricity.
“More research is needed, but our work is a promi- sing first step toward the development of personal power generators, actuators fors use in nano-devices, and other devices based on viral electronics,” says Seung-Wuk Lee, a faculty scientist in Berkeley Lab‘s Physical Biosciences Division and a UC Berkeley associate professor of bioengineering.
The Berkeley Lab researchers first had to determine if the M13 virus is piezoelectric. Lee turned to Ramesh, an expert in studying the electrical properties of thin films at the nanoscale. They applied an electrical field to a film of M13 viruses and watched what hap- pened using a special microscope. Helical proteins that coat the viruses twisted and turned in response-a sure sign of the piezoelectric effect at work.
Next, the scientists increased the virus‘s piezoelec- tric strength. They used genetic engineering to add four negatively charged amino acid residues to one end of the helical proteins that coat the virus. These residues increase the charge difference between the proteins‘ positive and negative ends, which boosts the voltage of the virus.
The scientists further enhanced the system by sta- cking films composed of single layers of the virus on top of each other. They found that a stack about 20 layers thick exhibited the strongest piezoelectric effect. The only thing remaining to do was a de- monstration test, so the scientists fabricated a virus- based piezoelectric energy generator. They created the conditions for genetically engineered viruses to spontaneously organize into a multilayered film that measures about one square centimeter. This film was then sandwiched between two gold-plated elec- trodes, which were connected by wires to a liquid- crystal display.
When pressure is applied to the generator, it pro- duces up to six nanoamperes of current and 400 millivolts of potential. That‘s enough current to flash the number “1” on the display, and about a quarter the voltage of a triple A battery.
Byung Yang Lee, Jinxing Zhang, Chris Zueger, Woo-Jae Chung, So Young Yoo, Eddie Wang, Joel Meyer, Rama- moorthy Ramesh & Seung-Wuk Lee: Virus-based piezo- electric energy generation, In: Nature Nanotechnology AOP, May 13, 2012, DOI:10.1038/nnano.2012.69:
http://dx.doi.org/10.1038/nnano.2012.69
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64 |
Page 65 |
Page 66 |
Page 67 |
Page 68 |
Page 69 |
Page 70 |
Page 71 |
Page 72 |
Page 73 |
Page 74 |
Page 75 |
Page 76 |
Page 77 |
Page 78 |
Page 79 |
Page 80 |
Page 81 |
Page 82 |
Page 83 |
Page 84 |
Page 85