Using nanomaterials to make fuel from sunlight

Mike Orcutt writes at Technology Review on

How Nanomaterials Can Help Make Fuel from Sunlight.

Researchers at the University of California, Berkeley, say that by combining nanoscale materials with bacteria, they have opened the door to a new way of designing systems that could efficiently turn carbon dioxide, water, and sunlight into useful organic compounds—similar to what plants do through photosynthesis. Down the road, they say, the system could become a commercially viable way to produce high-value chemicals like drug precursors used by the pharmaceutical industry, or to store renewable energy in the form of liquid fuels.

The new system is the first one in which semiconductors, which are capable of both capturing solar energy and transmitting electricity to the microbes, have been directly combined with bacteria, says Peidong Yang, a professor of chemistry and materials science at the University of California, Berkeley, and an inventor of the system. Previous similar systems have relied on bulky solar panels to provide renewable electricity (see “Making Diesel from CO2 and Sunlight”). In this case, semiconducting nanowires capture energy from sunlight and pass electrons to electrotrophic bacteria, which are nestled within the wires. The electrotrophs use the electrons to turn carbon dioxide and water into useful chemical building blocks. Those are then passed to genetically engineered E. coli, which in turn make a wide range of products.

Yang says his team’s ultimate goal is a synthetic system that is more stable than the bacteria-based system. But at the moment, he says, there are no better catalysts than bacteria for converting carbon dioxide into useful compounds. He and his colleagues are now looking closely at the way in which the semiconducting materials transfer electrons to the microbes. Investigating this semiconductor-bacteria interface could yield useful insights toward the design of a synthetic catalyst that could replace the bugs.

Read more here.

Nanodrones

Instapundit links to an article in Foresight Institute about the use of nanotechnology in medicine:

Microscopic drones which can seek out and repair sections of artery damage could signal the future of treatments for heart disease and strokes, scientists claim.

Successful tests of the nanodrones have been carried out in mice – and researchers hope to conduct the first human trials soon.

The tiny particles are 1,000 times smaller than the tip of a human hair, and are designed to latch on to atherosclerotic plaques – hard deposits made from accumulated fat, cholesterol and calcium that build up on the walls of arteries and are prone to rupture, producing dangerous clots.

Once they have attached, they release a drug derived from a natural protein which can repair damage in the body.

In the mice, scientists found that just five weeks of treatment resulted in significant repairs to artery damage while the plaques were shrunk and stabilised, making it less likely for fragments to break off and cause clots.…