A team of Swedish researchers are attempting to replicate photosynthesis as a means of converting solar energy to usable fuel.
“By converting carbon dioxide to fuel with the aid of solar energy, this technique could contribute to the development of sources of renewable energy and reduce the impact on the climate of the combustion of fossil fuels”, Jianwu Sun, senior lecturer in the Department of Physics, Chemistry and Biology at Linköping University told Nanowerk.
Graphene has shown much promise in the field of solar energy collection, and its ability to efficiently conduct electricity is well known. The team has developed a method of growing graphene on cubic silicon carbide, a material made of carbon and silicon. Upon heating, the silicon melts away leaving only the carbon atoms, which come together to form a graphene layer.
Combining the materials, the researchers have developed a photoelectrode capable of capturing the sun’s energy. The energy-absorbing silicon carbide is aided and protected by the graphene. By controlling the properties of the graphene-enhanced photoelectrode, it’s possible to control how the carbon dioxide is converted to energy using cathodes of different metals like copper or zinc. This enables the selective formation of various chemical compounds like methane or carbon monoxide.