An international team of researchers has demonstrated that solar-powered synthesis gas might convert carbon dioxide into fuels and valuable compounds.
Syngas can be used as a precursor for methanol and other chemicals and fuels if it can be produced from carbon dioxide using just solar energy.
Zetian Mi, a professor of electrical and computer engineering at the University of Michigan, conducted the study that was published in the Proceedings of the National Academy of Science.
He predicted that this would dramatically lower global CO2 emissions.
Syngas is often produced with the use of power from fossil fuels and consists primarily of hydrogen and carbon monoxide, with a little amount of methane.
To make the procedure more effective, harmful chemicals are frequently used.
Carbon dioxide converting to fuels using solar-powered chemistry
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According to Roksana Rashid, the study's first author, who conducted the experiments while a doctoral student in electrical and computer engineering at McGill University in Canada, "our new process is actually quite simple, but it's exciting because it's not toxic, it's sustainable, and it's very cost-effective," as cited by ScienceDaily.
Mi's team conquered the challenge of splitting carbon dioxide molecules, which are among the most stable in the universe, to develop a procedure that requires solely solar energy.
For this, they have strewn nanoparticles among a forest of semiconductor nanowires.
The carbon dioxide molecules were drawn to, and twisted by, those gold-coated chromium oxide nanoparticles, weakening the bonds between the carbon and oxygen.
The light energy was utilized by the gallium nitride nanowires to liberate electrons and the holes positively charged spaces they leave behind.
The protons (hydrogen) and oxygen were broken apart in the water molecules by the holes.
At the metal catalysts, the electrons divide the carbon dioxide to create carbon monoxide and, occasionally, methane by attracting free hydrogen.
The development of procedures to isolate oxygen from other gases.
Mi's team was able to regulate the proportions of hydrogen and carbon monoxide generated in the process by varying the gold to chromium oxide ratio in the nanoparticles.
This is significant because a fuel's or chemical's ease of manufacture depends on the hydrogen to carbon monoxide ratio.
Artificial photosynthesis, which uses solar energy to manufacture chemicals and fuels, has progressively gained popularity as awareness of climate change and the need for more sustainable chemical production has grown, as per Nature.
Even when sacrificial reagents are not necessary, the poor economic value of products like O2 has thus far prevented artificial photosynthesis from being scaled up.
As a result, there is increased interest in developing more sophisticated solar chemicals rather than sticking with straightforward processes like water splitting.
To combine light-harvesting and enzymatic catalysis with the added benefit of enantioselectively oxyfunctionalizing aliphatic hydrocarbons, semi-artificial photosynthetic systems have been created.
Complex natural products and active medicinal components have been synthesized asymmetrically using the combination of light and enzymatic catalysis.
These groundbreaking studies, however, called for excessive amounts of sacrificial redox agents, such as alcohols, or pricey platinum group photocatalysts, which will prevent their widespread use for synthetic photosynthesis.
The simultaneous oxidation of non-food biomass lignin by a photoelectrochemical platform in conjunction with the enzymatic reduction of CO2 or a-ketoglutarate has previously been demonstrated, though the substrate range was severely constrained, and toxic lead-containing perovskites were required for light harvesting.
The use of lignin as a photocatalyst to generate hydrogen peroxide from air and water without the need for sacrificial chemicals is now reported by Park, Hollmann, and colleagues in a paper published in Nature Synthesis.
This process can oxyfunctionalize aliphatic hydrocarbons with quantitative enantioselectivity when combined with unspecific peroxygenases (UPOs).
