Breakthrough in photocatalysts could help solve global warming, Korean scientists claim

Using photocatalysts to convert carbon dioxide into usable energy such as methane or ethane

Scientists in South Korea have conducted a range of experiments using photocatalysts in a bid to reduce carbon dioxide production to help solve global warming.

Photocatalysts refer to the action of employing a catalyst to speed up chemical reactions that requires or engages light. They are essential in converting carbon dioxide and water into hydrocarbon fuels.

The fresh research, led by Professor Su-Il In from the Department of Energy Science and Engineering at Daegu Gyeongbuk Institute of Science and Technology, demonstrates how the team successfully used high-efficiency photocatalysts to convert carbon dioxide into usable energy, such as methane or ethane.

This, they said, was done by placing graphene on reduced titanium dioxide in a stable and efficient way. This means the photocatalyst can selectively convert carbon dioxide from a gas to methane or ethane.

The results showed that its generation volume is 259umol/g and 77umol/g of methane and ethane respectively and its conversion rate is 5.2 per cent and 2.7 per cent higher than conventional reduced titanium dioxide photocatalysts.

"In terms of ethane generation volume, this result shows the world's highest efficiency under similar experimental conditions," the report states.

In its experiments, the research team also proved for the first time that the pore moves toward graphene due to band bending phenomena visible from titanium dioxide and graphene interfaces using photoelectron spectroscopy.

"The movement of the pore towards graphene activates reactions by causing electrons to gather on the surface of the reduced titanium dioxide and forms a large amount of radical methane as polyelectrons engage in the reactions," explains the study.

In the future, the catalyst material developed by the research team is expected to be applied to a variety of areas such as high-value-added material production.

Hoewever, more importantly, the plan is to use it to solve global warming problems and energy resource depletion issues, by selectively producing higher levels of hydrocarbon materials using sunlight.

"By conducting follow-up research that increases the conversation rate so that it can be commercialised, we will contribute to the development of technology for reducing carbon dioxide and turning it into a resource," explained professor Su-Il In.