Innovative achievement of Japanese scientists: production of clean fuel from sunlight and water
Japanese scientists have succeeded in building a prototype of a reactor that can produce renewable hydrogen fuel from sunlight and water. This reactor, with an area of 100 square meters, uses photocatalyst plates to separate oxygen and hydrogen atoms in water molecules, and as a result, hydrogen is extracted to be used as fuel.
Although the new technology is still in the early stages of development, researchers hope that by designing more efficient photocatalysts, it will be possible to produce hydrogen fuel at a lower cost and in a sustainable manner. The findings of this research have been published in the journal Frontiers in Science.
Kazunari DomanProfessor of Chemistry at Shinshu University in Japan, explaining this achievement to LiveScience: “Water splitting using sunlight and photocatalyst is one of the best ways to convert and store solar energy in chemical form. Although the recent developments in this area have been promising, there are still many challenges ahead of us.”
In the first step, oxygen is separated and in the next step, hydrogen is extracted
Photocatalysts are a type of catalyst that, by being exposed to light, accelerate chemical reactions that break down water molecules into hydrogen and oxygen. But most current photocatalysts that perform this process in a “one-step” manner have low efficiency. For this reason, hydrogen production is still heavily dependent on natural gas as a fossil source.
To overcome the limitations, the researchers designed a new photocatalyst with a two-step process in their project. In the first stage, oxygen is separated and in the next stage, hydrogen is extracted. This design allowed them to build a reactor that operated continuously for three years. Interestingly, the reactor’s performance in natural sunlight was even better than in tests based on UV light.
Takashi Hisatomi“Using a photocatalyst that is sensitive to ultraviolet light, the conversion efficiency of solar energy in natural sunlight increased by about 1.5 times,” says Shinshu University researcher and lead author of the study. He explained that the standard light simulated in the experiments uses a spectrum that is suitable for higher latitudes. However, in areas where sunlight has shorter wavelengths, the efficiency of the system can be even higher.
read more
Despite the advances, the current efficiency of the technology is still insufficient for commercial applications. “The efficiency of this process is at most one percent in simulated standard light, and not even five percent in natural sunlight,” emphasizes Hisatomi.
To increase efficiency, the researchers have asked other scientists to work on designing more optimized photocatalysts and building larger reactors. Also, process safety is very important; Because the production of hydrogen can create oxyhydrogen gas, which has explosive properties. Fortunately, the two-step process used in the new technology allows for the safe disposal of this gas.
Kazunari Duman added in the end: “What is most important is to increase the efficiency of converting solar energy into chemical energy. If the efficiency is improved to a practical level, the attention of researchers will be drawn to mass production, separation of gases and construction of large power plants. “This development will not only change the way policymakers look at solar energy, but will also accelerate the development of infrastructure, laws and regulations related to solar fuels.”
