To recreate photosynthesis in artificial conditions, it is necessary to repeat two key steps: the collection of solar energy and the splitting of water molecules. By the way, artificial photosynthesis can be used to produce both oxygen and hydrogen. In the second case, humanity will be reliably provided with environmentally friendly, efficient and inexpensive fuel.
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Sunscreen helped scientists turn air into fuel
While research into artificial photosynthesis is at the stage of laboratory development. Semiconductors and live bacteria are placed in a photosynthetic biogybrid system (artificial leaf), which is exposed to sunlight. Semiconductors collect its energy, generating the electrons necessary for the reaction in a solution of water and carbon dioxide to take place. The bacterium uses electrons to convert the carbon dioxide molecule, thereby promoting the formation of hydrogen (H2), methane (CH4), ethanol (C2H5OH). And water at the same time is oxidized on the surface of another semiconductor, during which oxygen is released.
Scheme of photosynthesis
But splitting the water molecule is not so simple, it requires about two and a half electron volts of energy. Therefore, we need a catalyst that “pushes” the chemical reaction.
Some researchers involved in artificial photosynthesis, imitate the natural process without involving living organisms. By and large these developments boil down to the creation of a fundamentally new catalyst, since existing (based on magnesium, titanium, cobalt, ruthenium) are quite toxic and have a low efficiency.
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Found ancient bacteria with resistance to modern antibiotics
There are developments on artificial photosynthesis, which use living organisms (so far only bacteria and single cells). Similar studies are based on obtaining information on photosynthesis with the help of cyanobacteria. First, a sequence of nucleotides is inserted into the genome, containing instructions for the synthesis of protein labels. Further, living organisms are extracted along with the tags and a study is made of the resulting photosystem (the bacteria that process the proteins). Scientists say that this information will help create artificial analogues of photosynthesis.