Researchers succeeded in developing a photo catalysts that converts carbon dioxide into usable energies such as methane or ethane.
A team of researchers at Department of Energy Science and Engineering developed a high-efficiency photocatalyst from semiconductors. In photocatalyst studies the semiconductor materials with large band gaps are used but often they are limited in absorbing solar energy. Therefore various researches are being taking place to improve the photocatalyst structure and surface to increase solar energy absorption areas.
The study was published on July 19, 2018 in the online edition of Energy and Environmental Science, an international journal on energy science. The researchers used graphene on reduced titanium dioxide in a stable and efficient way to develop the photocatalyst, which converts carbon dioxide into usable hydrocarbons. The photocatalyst selectively converts carbon dioxide from a mixture to methane or ethane. The observed results showed that the generation volume as 259umol/g and 77umol/g of methane and ethane respectively and its conversion rate is 5.2 percent and 2.7 percent higher than conventional reduced titanium dioxide photocatalysts.
According to the research team, the movement of the pore towards graphene was due to band bending phenomena visible from titanium dioxide that activates reactions by causing electrons to move on the surface of the reduced titanium dioxide and produces radical methane. They devised a mechanism for producing methane by reacting the radical methane with hydrogen ions.
In future, the photo catalyst could be applied to solve global warming problems and energy resource depletion issues by selectively producing higher levels of hydrocarbon, and also for producing high-value-added materials.