Tobacco plants can grow solar cells

Why build solar cells when you can grow them?

Infect tobacco plants with the right virus and they will produce solar cells for you.

Chop up the plants, extract the structures, and in theory you can spray them on a coated glass or plastic substrate, then harvest electricity.

The Nano Letters paper on this is causing quite a stir, bringing welcome publicity to Professor Matt Francis and his colleagues.

In the paper Francis (below) notes that the tobacco mosaic virus, which causes molting and discoloration of leaves, contains a protein coat that has long been studied by nanoscale researchers.

What they now have is a circular permutation of the protein that lines structures up to a center, can be seen in an electron microscope (above), that can be harvested in high yields, and that will self-assemble into  light-harvesting rods.

Best of all, these rods are stable across a wide pH range, allowing creation of geometries much like those found in nature.

But before we go spraying the world's tobacco fields, it's important to note Francis hasn't harvested electricity yet and that he's dealing more with a general method of mimicking photosynthesis, not saving tobacco farmers. Francis and his colleagues have also harvested solar cells from E.Coli bacteria.

What matters here is the marriage of organic processes for turning light into energy with the inorganic world of energy harvesting. Typical solar cells are made of silicon, which sits just below carbon on the periodic table. The atomic structures have a basic relationship.

So why build solar cells when you can grow them? That's what the Francis Research Group is working toward, not "synthetic" solar energy but truly green energy.

This post was originally published on Smartplanet.com