With lessons from nature, the sun’s energy can be used to create fuel from air, water and sunlight through artificial photosynthesis.
The sun provides a huge amount of energy to us each day, but capturing it is not so straightforward. Solar cells can make electricity from the sun’s light but storing and transporting this energy is difficult and expensive. One way of getting past this problem is through solar fuels – renewable energy obtained directly from sunlight, water, and CO2.
This energy route has been used by plants for millions of years in a process called photosynthesis, but this is somewhat inefficient. Artificial devices can reduce the amount of wasted energy and efficiently turn water and CO2 into products we can directly use.
In these devices semiconductor materials and visible light harvesters are used to absorb sunlight to drive a chemical reaction. The reaction could be converting CO2 into carbon-based fuels or splitting water into hydrogen and oxygen. However, this is challenging, and catalysts which lower the energy barrier are needed to help this work.
Fortunately, plants have the same problem so they developed their own ‘catalysts’ called enzymes to help them store energy. Studying these enzymes gives us insight into their molecular make-up and allows us to develop catalysts of our own. Tuning, testing, and anchoring these catalysts to semiconductors and light absorbers allows us to produce renewable fuels with a low energy cost.
Innovative design and implementation of these devices in the future could position solar fuels as a frontrunner in the global energy supply chain.
For more information visit: http://www-reisner.ch.cam.ac.uk/
Image from National Oceanic and Atmospheric Administration