Harnessing nature’s solar cells
Andreas Mershin, a research scientist in the Massachusetts Institute of Technology (MIT) Center for Bits and Atoms, managed to create an “electric nanoforest” comprised of zinc oxide nanowires and titanium dioxide nanostructure coated with a light-collecting material derived from bacteria. Mershin has extended upon a project begun by Shuguang Zhang, a principal research scientist at MIT, who was able to enlist a complex of molecules known as photosystem-1 (PS-1) – the tiny structures within plant cells that carry out photosynthesis – to produce an electric current when exposed to light. The initial system had some drawbacks and very low efficiency, but Mershin says the process has now been simplified to the point that virtually any lab could replicate it, and the new efficiency is 10,000 times greater than in previous versions. Still, it only converts 0.1 percent of sunlight’s energy into electricity, so an improvement of another tenfold is needed in order for the system to become useful.
The full publication of Mershin's work appeared in the open-access journal Sicnetific Reports: Self-assembled photosystem-I biophotovoltaics on Nanostructured TiO2 and ZnO.