Genetically-Modified Viruses Used to Create More Efficient Solar Cells

Here’s a novel use for the same little buggers that give you the sniffles and sneezes: solar energy.
Researchers from MIT have found a way to make solar cells up to one-third more efficient by using a virus to assemble microscopic structures consisting of carbon nanotubes. Specifically, the virus, called M13, is used to control the arrangement of nanotubes on the surface of the solar cell, keeping the tubes separate so they can’t short out, allowing more current to flow. Incorporating the viruses and their nanotube structures has shown to raise operating efficiency to 10.6 % from 8 %.
Here’s an explanation from MIT of how the viruses do their job:

The viruses actually perform two different functions in this process. First, they possess short proteins called peptides that can bind tightly to the carbon nanotubes, holding them in place and keeping them separated from each other. Each virus can hold five to 10 nanotubes, each of which is held firmly in place by about 300 of the virus’s peptide molecules. In addition, the virus was engineered to produce a coating of titanium dioxide (TiO2), a key ingredient for dye-sensitized solar cells, over each of the nanotubes, putting the titanium dioxide in close proximity to the wire-like nanotubes that carry the electrons.
The two functions are carried out in succession by the same virus, whose activity is “switched” from one function to the next by changing the acidity of its environment. This switching feature is an important new capability that has been demonstrated for the first time in this research, Belcher [Angela Belcher, MIT professor of energy] says.

Article from MIT: Solar power goes viral
Journal abstract: Virus-templated self-assembled single-walled carbon nanotubes for highly efficient electron collection in photovoltaic devices