A team of MIT Biological Material Group researchers has developed a way of using a modified virus as a kind of biological scaffold that can assemble the nanoscale components needed to split a water molecule into hydrogen and oxygen atoms.
During photosynthesis in plant cells, natural pigments absorb sunlight, while catalysts then promote the use of that energy to split water into its component hydrogen and oxygen molecules.
The MIT team, led by Professor Angela Belcher, engineered a common, harmless bacterial virus called M13 so that it would attract and bind with molecules of a biological pigment (in this case zinc porphyrins) and a catalyst (iridium oxide). The virus acts as a kind of scaffolding, causing the pigments and catalysts to line up with the right spacing to trigger the water-splitting reaction.
Using the virus to make the system assemble itself improves the efficiency of the oxygen production fourfold.
Currently, the hydrogen atoms from the water get split into their component protons and electrons. The team is working on a second part of the system which will combine these back into hydrogen atoms and molecules which could be stored for use as a fuel.
The team is also working to find a less-expensive material than iridium oxide for the catalyst.
Professor Belcher says that she expects to have a prototype device that can carry out the whole process of splitting water into oxygen and hydrogen, using a self-sustaining and durable system, within two years.