Pukyong National University

Notice! 'Carbon dioxide as a liquid fuel', research on artificial photosynthesis
PKNU Professor Kim Chang-woo developed high-efficiency artificial photosynthesis system

△ Image of Selective Synthesis of Methanol and Ethanol with and without Nafion Polymer Layer.

A highly efficient artificial photosynthesis system that converts carbon dioxide, one of the greenhouse gases, into liquid fuel, methanol and ethanol, has been developed.

Professor Kim Chang-woo (Dept. of Graphic arts information engineering) of Pukyong National University recently developed a CO2 reduction device with faradaic efficiency of methanol and ethanol of 60% and 90% each, together with a team of Professor Kang Young-soo of Korean Center for Artificial Photosynthesis (KCAP).

Faradaic efficiency is the ratio of the energy used to produce the actual organic compound among the energy used to convert carbon dioxide to organic compounds.

Recently, research has been focused on the production of useful chemical materials such as liquid fuels by artificially reverting carbon dioxide, such as photosynthesis of plants, however there has been a limit that the faradaic efficiency is lowered due to the separation process for the final product when carbon dioxide is reverted.

The photocatalyst (TiO2) coated with a photo-electrode (BiVO4) with increased optical activity and a Nafion polymer layer was used as an oxidizing electrode and a reverting electrode of a carbon dioxide reduction reactions respectively, to cause a carbon dioxide reducing reaction in the organic solvent electrolyte.

The device is designed to selectively form methanol or ethanol as the result product of carbon dioxide reduction depending on the presence or absence of Nafion layer, resulting in high Faradaic efficiency.

Professor Kim also presented a mechanism for the selective reduction of carbon dioxide through joint research with Fudan University, China.

The paper, 「Selective Alcohol on Dark Cathodes by Photoelectrochemical CO2 Valorization and Their In Situ Characterization」, published recently in the ACS Energy Letters (Impact Factor 16.3) of the American Chemical Society (ACS), a prominent international scientific journal in chemistry. <Pukyong Today>

△ Role Image of Nafion Polymer Layer for Selective Methanol Synthesis.