Solar energy devices convert CO2 into fuel

Chemical experts at the University of California, San Diego have demonstrated the feasibility of harnessing sunlight to transform greenhouse gas emissions into useful products.

While there are a lot of ' Earth Week ' activities that focus attention on whether CO2 is rising in the atmosphere or impacts on global climate, Clifford Kubiak, professor of chemistry and biochemistry, is now His graduate student Aaron Sathrum is developing a prototype device that can capture solar energy and transform it into electrical energy as well as ' splitting ' CO ₂ into CO and oxygen.

Because this device has not been evaluated optimistically, experts still need to collect more energy to research. However, they hope the research results will promise a new method after being presented at the meeting with the American Chemical Society last month.

According to Professor Kubiak, every time there is a mention of CO ₂ separation, there will be more than 100 items about splitting water to create hydrogen, though separating CO ₂ will take full advantage of just creating a dent, besides. Separation of CO ₂ also helps create CO - an important industrial chemical that is usually made from natural gas. So with the separation of CO ₂ we can save fuel, create a useful chemical while reducing the greenhouse effect .

The semiconductor device also called the CO ₂ splitting device being developed (thin gallium photphin sponge with metal contacts) - (Photo: Zeenews.com)

Although CO is toxic, it is likely to lack much later. Every year millions of pounds of CO are used to make chemicals such as detergents and plastics, and are also used to convert into liquid fuels.

Professor Kubiak added that the technique of converting CO into liquid fuel was known a long time ago, it was invented in Germany in 1920. And the United States is very interested in this technique during the energy crisis period. 1970, but after the crisis ended, that concern was no longer available. It is now time to proceed because of rising fuel prices, making the conversion of CO into fuel economically competitive.

The device used to separate CO ₂ was designed by Professor Kubiak and his graduate student Sathrum by taking advantage of a semiconductor device with 2 layers of thin catalysts . It helps separate CO ₂ to produce CO and oxygen with a three-step process, first collecting light quanta through a semiconductor device, then converting the energy of energy into electrical energy through semiconductor devices, and finally deploying electrical energy into catalysts, these catalysts convert CO2 into CO to one side of the device and the other side from oxygen.

Because quantum is moved around these reactions, a special catalyst can convert electrical energy into chemical energy that researchers need, and the catalyst has created a large molecule with 3 nickel at the center, this proves to be an effective catalyst for the separation process.

According to research experts, choosing the right semiconductor device is also important in implementing CO ₂ separation. Semiconductor devices have energy belts adjacent to electrons. Sunlight makes electrons pass from the belt to the ability to create the next electronic energy. The difference in energy between these belts - also known as the energy gap, determines how much solar energy is absorbed and how much electrical energy is produced.

Prof Kubiak and Sathrum initially used a good silicon semiconductor device for testing device quality. However, silicol is absorbed in the infrared range and they think it is too weak to provide enough energy. The conversion of sunlight with silicol provided half of the energy needed to separate CO2 and the reaction would work if the researchers were to supply the rest of the energy needed.

They are currently using a device that uses semiconductors, gallium and photphin. It has twice the energy gap of silicol which absorbs light energy. Therefore, it is predicted that it will absorb an optimal amount of energy to develop CO ₂ catalytic decomposition.

According to Sathrum graduate student, this project has brought together many disciplines of science, each of them is a little researched, and connecting them all together is a matter of focus.

The research is supported by the US Department of Energy

Anh Phuong

According to University of California - San Diego, Dong Nai Department of Science and Technology