Converting the energy from sunlight into a useful electric potential in order to charge a battery or power a lightbulb is almost always carried out by silicon solar panels. There are a lot of good reasons why silicon is used for light collection, but there is no reason this process must rely on this material. In fact, one reason to look at other possible materials is that nature itself has a number of materials that convert light energy into electrochemical gradients.
The capacity to harvest light energy and use it for powering the cell is ancient, having evolved on Earth at least 1 billion years ago. We find the results of this in all of the true plants today, as well as numerous algae and phytoplankton. But it’s also found in many more primitive organisms, and they may have some tricks for collecting light efficiently that could prove useful as a model to follow for solar technology. That’s exactly what a research group has been working on at the Photosynthetic Antenna Research Center at Washington University.
Taking a page out of the way primitive photosynthetic cells harvest light, they have found a way to assemble the pigments needed to harvest light by studying a structure called the chlorosome, found in photosynthetic green bacteria. Unlike the high degree of structural specialization found in land plant chloroplasts, these bacteria lack any such specialization, instead relying on the chlorosome region to harvest light. It is the self-assembling nature of the pigments into the chlorosome that the researchers find to have potential application in the development of alternative solar technology. Seems obvious to look throughout nature to solve difficult problems like these, and to provide the funds in basic research to do so.
Gravitropic 