30. September 2011
Artificial leaf. (Photo: mit.edu.com)
As anybody who has finished elementary school will know, plants are one of the most versatile life forms on earth due to their ability to not only produce their own food but their own energy, by the process of photosynthesis and with the help of chlorophyll. However, no matter how much we try, we have never been able to come up with a inexpensive and viable way of producing eco-friendly energy. Even wind and solar energy, while green, are still relatively unused and undeveloped leaving us with a huge green energy supply deficit on a global scale. But now, a team of scientists from the Massachusetts institute of technology have invented a device that may be the answer to all the global green energy crisis: an artificial leaf that produces energy from the sun!
This artificial leaf will be no bigger than an ordinary leaf and will use the energy from the sun to create a chemical reaction that can store the resulting energy for later use. However, the significance of this gizmo is that it is completely operated by the sun’s energy and does not require any wires or external electrical sources to operate. It is also made very cheaply from some of the commonly occurring minerals like iron, silicon and cobalt. On a basic level, this artificial leaf will just be a thin plate of silicon with a cobalt based catalyst bound on its one side and a zinc alloy based catalyst bound on the other.
In order to operate this device, all you have to do is place it in a clear container of water and the chemical reactions will do the rest. Once the sunlight hits the silicon chip, it will cause it to release bubbles of hydrogen and oxygen on two different sides of the bowl, with the help of the aforementioned catalysts. The cobalt catalyst will be responsible for releasing oxygen bubbles and the zinc catalyst will oversee the release of hydrogen bubbles. Now that the water is bubbling with hydrogen and oxygen, all the scientists had to do was create a barrier in the water to separate the bubbles, which meant that they had free hydrogen and oxygen at their disposal for future energy usage.
While this device mostly operated without wires, Dr Daniel Nocera, who worked as a chief researcher on this project claimed that without wires, this device may convert 2.5 to 3 percent of all the sunlight into energy, but with the help of wires, the numbers could increase to 5 to 6 percent, which is quite and achievement considering this device is still in its beta stage.
But even though the device is still in its prototype form, it has still managed to perform all the tasks very well, which means that after some more development, it can be altered and be used on a nanoscale level which would create energy which much greater efficiency then its present form. Nevertheless, according to Nocera, the device still is not ready for commercial use and needs to get some bugs fixed. However, this invention may help us create a future where we will be able to solve all our energy related woes, without hurting the environment.