Scientists figure out way to convert CO2 into carbon monoxide using visible light

Washington, March 9 (ANI): A team of scientists has figured out a way to efficiently turn carbon dioxide (CO2), a greenhouse gas, into carbon monoxide using visible light, like sunlight.

The method was developed by University of Michigan biological chemist Steve Ragsdale, along with research assistant Elizabeth Pierce and scientists led by Fraser Armstrong from the University of Oxford in the UK.

Ragsdale and his associates succeeded in using an enzyme-modified titanium oxide to get carbon dioxide's electrons excited and willing to jump to the enzyme, which then catalyzes the reduction of carbon dioxide to carbon monoxide.

A photosensitizer that binds to the titanium allows the use of visible light for the process.

The enzyme is more robust than other catalysts, willing to facilitate the conversion again and again.

The trick is that it can't come near oxygen.

"By using this enzyme, you put it into a solution that contains titanium dioxide in the presence of a photosensitizer," Ragsdale said.

"We looked for a way that seems like nature's way of doing it, which is more efficient," he added.

According to Armstrong, "Essentially, it shows what is possible were we to be able to mass-produce a catalyst with such properties".

The direct product - carbon monoxide - is a desirable chemical that can be used in other processes to produce electricity or hydrogen.

Carbon monoxide also has significant fuel value and readily can be converted by known catalysts into hydrocarbons or into methanol for use as a liquid fuel.

Not only is it a demonstration that an abundant compound can be converted into a commercially useful compound with considerably less energy input than current methods, it also is a method not so different from what organisms regularly do.

"This is a first step in showing it's possible, and imagine microbes doing something similar," Ragsdale said.

"I don't know of any organism that uses light energy to activate carbon dioxide and reduce it to carbon monoxide, but I can imagine either finding an organism that can do it, or genetically ngineering one to channel light energy to coax it to do that," he added. (ANI)