Currently, an extremely large proportion (85%) of the world’s power supply is being derived from the burning of fossil fuels. This means of energy production is associated with a host of seemingly insurmountable problems such as climate change and oil spills. The search is on to find feasible and renewable power sources – and artificial photosynthesis may be the answer.
One promising method relies on the power of the sun to aid in the creation of energy-rich, fuel molecules, in a way inspired by the biological process of photosynthesis. This method, aptly called “artificial photosynthesis”, uses sunlight to split water into hydrogen and oxygen. A chemical fuel consisting of this hydrogen can then be used as an energy source. Hydrogen is an incredible source of energy, containing the highest energy density out of all fuels. Most importantly, it is a clean and emission-free energy source that can be stored for future use.
Artificial photosynthesis has been explored several times in the past but has not been considered a feasible means of energy production for a variety of reasons, including high cost and the unavailability of materials. It was not until last year that a viable method of artificial photosynthesis was proposed.
Enter the “artificial leaf” produced by Dr. Daniel Nocera’s lab group at MIT. After being placed in a beaker of water, the “artificial leaf” uses photons from sunlight to break up water molecules into hydrogen and oxygen. This silicon solar cell succeeds where many of its predecessors have failed. The reason for this success can be partially attributed to the use of a cobalt-based catalyst. Inexpensive and abundant, the use of this metal as a catalyst is an important new innovation. All other materials utilized, such as silicon, cobalt and nickel, are relatively cheap and widely used, leaving out the more expensive materials, such as platinum. The “artificial leaf” also uses water as a solvent instead of the incredibly acid or alkaline solutions used in the past.
It is this portability and low price that make this solar cell such a promising technology. The “artificial leaf” would be an excellent candidate for the provision of energy to places where access to electricity is shaky or non-existent. Further research needs to be undertaken with this technology, as its efficiency is much lower than commercial solar cells currently on the market. However, it is undoubtedly a step in the right direction.