[amor de cosmos]

Researchers find rust can power up artificial photosynthesis
Boston College chemists produce power boost critical to novel energy harvesting applications

CHESTNUT HILL, MA (Oct. 11, 2013) – Chemists at Boston College have achieved a series of breakthroughs in their efforts to develop an economical means of harnessing artificial photosynthesis by narrowing the voltage gap between the two crucial processes of oxidation and reduction, according to their latest research, published this week in the journal Angewandte Chemie.

The team reports it has come within two-tenths of the photovoltage required to mimic oxidation and reduction respectively using unique photoanodes and photocathodes the team developed using novel nanowire components and coatings. Narrowing the gap using economical chemical components, the group moves researchers closer to using the man-made reaction for unique applications such as solar energy harvesting and storage.

"Many researchers have been trying to harvest solar energy and directly store it in chemical bonds," said lead author Dunwei Wang, an associate professor of chemistry at Boston College. "Solar panels can harvest energy, but economical storage has remained elusive. We are trying to borrow a page from Mother Nature whereby photosynthesis produces energy from the sun and stores it."

But copying Mother Nature is a tall order and this particular quest "requires materials that can absorb sunlight broadly, transfer the energy to excited charges at high efficiencies and catalyze specific reduction and oxidation reactions," the team writes in the article "Hematite-Based Water Splitting with Low Turn-on Voltage."

Natural photosynthesis consists of two important processes. Oxidation produces oxygen gas. Reduction produces organic molecules. Wang said artificial photosynthesis, also known as water splitting, tries to copy these two reactions using a photoanode to oxidize water and a photocathode to either reduce water for hydrogen production or to reduce carbon dioxide for organic molecules.

http://www.eurekalert.org/pub_releas...-rfr101013.php