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Artificial Forest for Solar Water-Splitting

By Guest PostJune 14, 2013Environmentartificial forest, atmospheric carbon dioxide, berkeley lab, bin liu, carbon neutral, chloroplasts, chong liu, fuel conversion, green plants, hao ming chen, hydrogen generating photocathode, jinyao tang, nanowire heterostructures, natural photosynthesis, ohmic contact, oxidation half reactions, oxygen molecules, peidong yang, photosynthesis, reduction, renewable energy, silicon, solar, solar water splitting, stable semiconductors, titanium oxide, z scheme

Berkeley Lab Researchers Report First Fully Integrated Artificial Photosynthesis Nanosystem

In the wake of the sobering news that atmospheric carbon dioxide is now at its highest level in at least three million years, an important advance in the race to develop carbon-neutral renewable energy sources has been achieved. Scientists with the U.S. Department of Energy (DOE)’s Lawrence Berkeley National Laboratory (Berkeley Lab) have reported the first fully integrated nanosystem for artificial photosynthesis. While “artificial leaf” is the popular term for such a system, the key to this success was an “artificial forest.”

“Similar to the chloroplasts in green plants that carry out photosynthesis, our artificial photosynthetic system is composed of two semiconductor light absorbers, an interfacial layer for charge transport, and spatially separated co-catalysts,” says Peidong Yang, a chemist with Berkeley Lab’s Materials Sciences Division, who led this research. “To facilitate solar water- splitting in our system, we synthesized tree-like nanowire heterostructures, consisting of silicon trunks and titanium oxide branches. Visually, arrays of these nanostructures very much resemble an artificial forest.” (more…)

A Dual Look at Photosystem II Using the World’s Most Powerful X-Ray Laser

By Guest PostFebruary 27, 2013Sciencealgae, berkeley lab, carbon dioxide, catalytic activities, cryogenic temperatures, cyanobacteria, data, earth, energy, free electron laser, green plants, jan kern, junko yano, laser pulses, lcls, light source, linac coherent, living cells, manganese calcium, metal ion, metalloenzyme crystal, metalloenzymes, mn4ca, molecular oxygen, most powerful, natural photosynthesis, nicholas sauter, nitrogen fixation, oxidation states, photo reduction, photon step cycle, photon steps, photosystem, protein complex, proteins, radiation damage, roberto alonso mori, s1 to s4, sensitive to radiation, simulate solar photons, slac, software tools, sunlight, uwe bergmann, vital to life, vittal yachandra, water, water molecules, world, xes, xfel, xray beams, xray diffraction, xray emission spectroscopy, xray laser, xrd

Berkeley Lab and SLAC Researchers Demonstrate Room Temperature Simultaneous Diffraction/Spectroscopy of Metalloenzymes

From providing living cells with energy, to nitrogen fixation, to the splitting of water molecules, the catalytic activities of metalloenzymes – proteins that contain a metal ion – are vital to life on Earth. A better understanding of the chemistry behind these catalytic activities could pave the way for exciting new technologies, most prominently artificial photosynthesis systems that would provide clean, green and renewable energy. Now, researchers with the U.S. Department of Energy (DOE)’s Lawrence Berkeley National Laboratory (Berkeley Lab) and the SLAC National Accelerator Laboratory have taken a major step towards achieving this goal.

Using ultrafast, intensely bright pulses of X-rays from SLAC’s Linac Coherent Light Source (LCLS), the world’s most powerful X-ray laser, the researchers were able to simultaneously image at room temperature the atomic and electronic structures of photosystem II, a metalloenzyme critical to photosynthesis. (more…)

A New Way of Looking at Photosystem II

By Guest PostJune 14, 2012Sciencealgae, angstroms, bacteria, berkeley lab, carbon dioxide, catalytic cycle, critical formation, cryogenic freezing, electrochemical energy, electrons, femtosecond timescale, femtosecond x ray pulses, green, green plants, hydrogen atom, hydrogen ions, jan kern, junko yano, knowledge, lcls, microcrystals, nicholas sauter, oxidation states, oxygen molecules, paul adams, photooxidation, photosynthesis, photosystem ii, protein crystallography, proteins, protons, renewable energy, resolution, slac, solar energy, synchrotron radiation, terabytes of data, uwe bergmann, vittal yachandra, water, xray diffraction, xrays

Berkeley Lab and SLAC Researchers Study Key Protein Complex Crucial to Photosynthesis

Future prospects for clean, green, renewable energy may hinge upon our ability to mimic and improve upon photosynthesis – the process by which green plants, algae and some bacteria convert solar energy into electrochemical energy. An artificial version of photosynthesis, for example, could use sunlight to produce liquid fuels from nothing more than carbon dioxide and water. First, however, scientists need a better understanding of how a large complex of proteins, called photosystem II, is able to split water molecules into oxygen, electrons and hydrogen ions (protons). A new road to reaching this understanding has now been opened by an international team of researchers, led by scientists at the U.S. Department of Energy (DOE)’s Lawrence Berkeley National Laboratory (Berkeley Lab) and SLAC National Accelerator Laboratory.

Using ultrafast, intensely bright pulses of X-rays from SLAC’s Linac Coherent Light Source (LCLS), the research team produced the first ever images at room temperature of microcrystals of the photosystem II complex. Previous imaging studies, using X-rays generated via synchrotron radiation sources, required cryogenic freezing, which alters the samples. Also, to catalyze its reactions, photosystem II relies upon an enzyme that contains a manganese-calcium cluster that is highly sensitive to radiation. With the high-intensity femtosecond X-ray pulses of the LCLS, the research team was able to record intact images of these clusters before the radiation destroyed them. (more…)

The Heart of The Plant

By Guest PostDecember 10, 2011Sciencegreen plants, heart of plant, molecular pump

Palo Alto, CA — Food prices are soaring at the same time as the Earth’s population is nearing 9 billion. As a result the need for increased crop yields is extremely important. New research led by Carnegie’s Wolf Frommer into the system by which sugars are moved throughout a plant—from the leaves to the harvested portions and elsewhere—could be crucial for addressing this problem. Their work is published December 8 by Science Express. (more…)

Tag Archives: green plants

Artificial Forest for Solar Water-Splitting

A Dual Look at Photosystem II Using the World’s Most Powerful X-Ray Laser

A New Way of Looking at Photosystem II

The Heart of The Plant