Nanowire–Bacteria Hybrids for Unassisted Solar Carbon Dioxide Fixation to Value-Added Chemicals – WHAT ! ! !
In natural photosynthesis, CO2 is first reduced to common biochemical building blocks using solar energy, which are subsequently used for the synthesis of the complex mixture of molecular products that form biomass.
Direct solar-powered production of value-added chemicals from CO2 and H2O, a process that mimics natural photosynthesis, is of fundamental and practical interest.
Scientists at the U.S. Department of Energy’s Lawrence Berkeley National Laboratory and the University of California, Berkeley, have developed a nanosystem that successfully mimics the natural process of photosynthesis. However, unlike natural photosynthesis, wherein carbon dioxide and water are used to synthesize carbohydrates in the presence of sunlight, this artificial system synthesizes acetates — the most common building blocks for biosynthesis that can eventually be used to produce drugs and biofuels.
“We believe our system is a revolutionary leap forward in the field of artificial photosynthesis,” Peidong Yang, a chemist with the lab’s Materials Sciences Division and one of the authors of the study, published in the journal Nano Letters, said, in a statement. “Our system has the potential to fundamentally change the chemical and oil industry in that we can produce chemicals and fuels in a totally renewable way, rather than extracting them from deep below the ground.”
The high-surface-area silicon nanowire array harvests light energy to provide reducing equivalents to the anaerobic bacterium, Sporomusa ovata, for the photoelectrochemical production of acetic acid under aerobic conditions.
The resulting acetate can be activated to acetyl coenzyme A by genetically engineered Escherichia coli and used as a building block for a variety of value-added chemicals. As such, interfacing biocompatible solid-state nanodevices with living systems provides a starting point for developing a programmable system of chemical synthesis entirely powered by sunlight.