For most of us, solar power comes from solar panels that sit on the roof and generate electricity. Overwhelmingly, the core material used to convert light into power is silicon. There are regular background rumblings about the possibility of demand exceeding the supply of pure silicon, with consequences for the take-up of solar technologies. No wonder scientists are looking for alternatives, as pointed out by Matt in his ‘Solar News‘ post.
Researchers at the New Jersey Institute of Technology have developed a carbon-based solar cell that may one day enable householders to print their own solar panels onto plastic sheets using a standard inkjet printer. Lead researcher and author Somenath Mitra said: “Developing organic solar cells from polymers is a cheap and potentially simpler alternative. We foresee a great deal of interest in our work because solar cells can be inexpensively printed or simply painted on exterior building walls and/or roof tops. Imagine some day driving in your hybrid car with a solar panel painted on the roof, which is producing electricity to drive the engine. The opportunities are endless.”
The new cells use carbon nanotubes in combination with tiny carbon buckyballs (known as fullerenes) to form snake-like structures. Buckyballs trap electrons, although they can’t make electrons flow. Add sunlight to excite the polymers, and the buckyballs will grab the electrons. Nanotubes, behaving like copper wires, will then be able to make the electrons or current flow. “Using this unique combination in an organic solar cell recipe can enhance the efficiency of future painted-on solar cells,” said Mitra. “Someday, I hope to see this process become an inexpensive energy alternative for households around the world.”