New breakthrough in artificial photosynthesis

The method of developing "artificial photosynthesis" in some bacteria can help create valuable products, and this is a breakthrough in the field of science that contributes to significantly improving children's lives. people and contribute significantly to preventing some environmental problems today.

New step of artificial photosynthesis

A new breakthrough in artificial photosynthesis achieved with the development of a system can collect carbon dioxide emissions and convert them into valuable chemical products, including biodegradable plastics, pharmaceuticals and even liquid fuels.

Developed by scientists from Lawrence Berkeley National Laboratory and California Berkeley University, the system uses the hybrid arrangement of semiconductor nanoparticles and bacteria to mimic natural photosynthesis like Green plants use solar energy to synthesize carbohydrates from CO2 and water.

However, this new artificial photosynthesis system synthesizes combinations of carbon dioxide and water that make up acetate - a flexible, most common precursor to today's synthetic biology.

'We believe this system is a great leap forward in the field of artificial photosynthesis , ' said Peidong Yang, Berkeley Laboratory chemist, and at the same time one of the people leading the study. .

This groundbreaking artificial photosynthesis system has four main tasks: (1) solar energy collection, (2) generating reduction equivalents, (3) reducing CO2 into biological synthesis medium, and (4) create useful chemicals (Photo: Berkeley Laboratory)

'Our system is capable of substantially altering the chemical and fuel industries, in this way we can create chemicals and fuels in a completely renewable way, without having to exploit. they are from deep within the earth. '

'During natural photosynthesis, leaves absorbing solar energy and carbon dioxide are reduced, combined with water for the synthesis of molecular products to form biomass,' explained researcher Chris Chang. .

'In our system, micro-fibers are obtained from solar energy and provide electrons to bacteria, where carbon dioxide is reduced and combined with water to produce products.'

By combining biocompatible nanotubes with selective bacterial populations , a new artificial photosynthesis system can contribute to the benefits of both: solar - chemical Green matter is used to separate carbon dioxide.

The system proceeds with an 'artificial tree forest ' of nano-fiber hidden quantum data including silicon nanofibers and titanium oxide. 'Our artificial forests are like green chloroplasts , ' Yang explained.

'When sunlight is absorbed, the electron-hole optical stimuli (semiconductors) are created in silicon nanofibres and titanium oxide, which absorb different regions of the spectrum. Sun. The photogenerated electrons (photogenerated) in silicon will enter the bacteria to reduce carbon dioxide while photo-generated holes in titanium oxide divide water molecules to produce oxygen.

When the forest created by nanofibers is set up, this is a collection of artificial populations that can create enzymes known as catalysts that contribute to the reduction of carbon dioxide selectively. filter.

In this study, the Berkeley University team used an anaerobic bacterium called Sporomusa ovate ready to receive electrons directly from the environment and use them to contribute to reducing carbon dioxide.

' Sporomusa ovate is an excellent carbon dioxide catalyst because it produces acetate, a versatile intermediate chemical that can be used to produce a diverse array of beneficial chemicals , ' Michelle Chang University of Berkeley researchers shared.

'We can plug components that unify the array of nanofibers with S. ovata using brackish water along with trace vitamins as the only organic ingredient.'

Once carbon dioxide is reduced by S. ovata to acetate (or some other intermediate chemical synthesis), genetically modified E. coli bacteria are used to synthesize used chemical products. to synthesize target chemical products.

To increase the yield of chemical products, S. ovata and E.coli bacteria were kept separately in this study. In the future, two promotion and synthesis activities can be combined into a single process.

The key to the success of artificial photosynthesis is the separation of the strict requirements of light-emitting efficiency and catalytic activity that can be generated by nanofibre / bacterial hybridization technology.

With this method, the Berkeley University team obtained the conversion efficiency of solar energy up to 0.38% in about 200 hours under simulated sunlight.

The production of acetate-produced chemical molecules is also encouraged, a high proportion of 26% for making butanol - a better biofuel than a one-fuel ethanol similar to gasoline, 25% for Amorphadiene. (precursor of antimalarial drugs Artemisinin), 52% for renewable plastic and biodegradable PHB. Improved experiments are expected along with many technological improvements.

The team is currently working on a second-generation system that has a conversion efficiency from solar energy to 3% chemical energy . When the research team achieves a 10% conversion efficiency, the technology will be commercially viable.