Artificial Photosynthesis can help solve carbon emission problem: Study

Washington: A new research has suggested that there is a possibility that carbon emission problem of the world might be solved by a potentially game-changing breakthrough in artificial photosynthesis.

A potentially game-changing breakthrough in artificial photosynthesis has been achieved with the development of a system that can capture carbon dioxide emissions before they are vented into the atmosphere and then, powered by solar energy, convert that carbon dioxide into valuable chemical products, including biodegradable plastics, pharmaceutical drugs and even liquid fuels.

Scientists with the U.S. Department of Energy (DOE)'s Lawrence Berkeley National Laboratory (Berkeley Lab) and the University of California (UC) Berkeley have created a hybrid system of semiconducting nanowires and bacteria that mimics the natural photosynthetic process by which plants use the energy in sunlight to synthesize carbohydrates from carbon dioxide and water.

However, this new artificial photosynthetic system synthesizes the combination of carbon dioxide and water into acetate, the most common building block today for biosynthesis.

By combining biocompatible light-capturing nanowire arrays with select bacterial populations, the new artificial photosynthesis system offered a win/win situation for the environment: solar-powered green chemistry using sequestered carbon dioxide.

A key to the success of their artificial photosynthesis system was the separation of the demanding requirements for light-capture efficiency and catalytic activity that is made possible by the nanowire/bacteria hybrid technology. With this approach, the Berkeley team achieved a solar energy conversion efficiency of up to 0.38-percent for about 200 hours under simulated sunlight, which was about the same as that of a leaf.

The yields of target chemical molecules produced from the acetate were also encouraging, as high as 26-percent for butanol, a fuel comparable to gasoline, 25-percent for amorphadiene, a precursor to the antimaleria drug artemisinin, and 52-percent for the renewable and biodegradable plastic PHB. Improved performances are anticipated with further refinements of the technology.