Man-made Photosynthesis Devices Becomes More Efficient Over Time
Photosynthesis device mimics the natural photosynthesis by turning CO2 and water into energy with the help of sunlight.
Devices that imitate the process of natural photosynthesis where plants turn carbon dioxide and water into energy with the help of sunlight could help us deal with various environmental issues one day. Scientists demonstrated this new technology that along with producing cleaner hydrogen fuel, can even undergo morphological changes in the course of its use, increasing its efficiency over time.
Scientists from Lawrence Livermore National Laboratory and University of Michigan (UM) carried out this research, which was published in the journal Nature Materials. The team was working with a previous artificial photosynthesis device developed by Prof. Zetian Mi, UM engineer. The device offers a cleaner way to produce hydrogen, which generally involves usage of electrical energy or natural gas, by harnessing the sunlight for splitting salt and fresh water and generating hydrogen to utilize within fuel cells.
In spite of publishing these results in 2018, scientists continued to study the device further for better understanding the logic behind its high efficiency. A series of advanced spectroscopy and microscopy techniques were used by the team to watch the materials working, and revealed some surprises.
While the performance of any artificial device of photosynthesis would be generally expected to decline in some hours due to the wear out of materials, this device actually became more efficient as time passed. The researchers observed that the tops of gallium nitride towers formed new places for producing hydrogen by taking new properties and absorbing oxygen, forming a material called gallium oxynitride, as they used the system. In their further steps, researchers will conduct experiments with materials as a part of an entire photoelectrochemical cell to split water, including exploring the similarity in materials might increase the stability of the system even more.
“We discovered an unusual property in the material that enables it to become more efficient and stable,” says the paper's senior author, Francesca Toma. “Our discovery is a real game-changer. I’ve never seen such stability.”