Friday, January 21, 2011

This week in nanotechnology - January 21, 2011

To rebuild damaged parts of a human body from scratch is a dream that has long fired human imagination, from Mary Shelley's Doctor Frankenstein to modern day surgeons. Now, a team of European scientists, working in the frame of the EUREKA project ModPolEUV, has made a promising contribution to reconstructive surgery thanks to an original multidisciplinary approach matching cutting-edge medicine to the latest developments in nanotechnology. They managed to develop a new and simple way to create nanostructured materials that would allow a better development of human cells.

Measuring the attractive forces between atoms and surfaces with unprecedented precision, University of Arizona physicists have produced data that could refine our understanding of the structure of atoms and improve nanotechnology. To study the van-der-Waals force,the team designed a sophisticated experimental setup that can measure the interactions between single atoms and a surface.

Scientists have coaxed polymers to braid themselves into wispy nanoscale ropes that approach the structural complexity of biological materials. Their work is the latest development in the push to develop self-assembling nanoscale materials that mimic the intricacy and functionality of nature's handiwork, but which are rugged enough to withstand harsh conditions such as heat and dryness.

A nanoscale rope that braids itself, as seen in this atomic force microscopy image of the structure at a resolution of one-millionth of a meter.

Researchers at Northwestern University have placed nanocrystals of rock salt into lead telluride, creating a material that can harness electricity from heat-generating items such as vehicle exhaust systems, industrial processes and equipment and sun light more efficiently than scientists have seen in the past. The material exhibits a high thermoelectric figure of merit that is expected to enable 14 percent of heat waste to electricity, a scientific first.

Butterfly wings behind anti-counterfeiting nanotechnology: Researchers are using nanoholes to create unique anti-counterfeiting security features. How this works is microscopic gratings composed of nanostructures interact with light to produce the shimmering iridescence seen on the Costa Rican morpho butterfly. The nanostructures act to reflect and refract light waves to produce the morpho's signature blue wings and absorb other unwanted light.

In solar cells and photodetectors, an optical radiation excites electrons to higher energy states, thereby a photocurrent begins to flow. Scientists have now found a way to directly measure the time during which photo-excited electrons flow in nanoscale photodetectors.

University of Illinois materials scientists have developed a simple, generalizable technique to fabricate complex structures that assemble themselves. Their advance utilizes a new class of self-assembling materials that they developed. The team demonstrated that they can produce a large, complex structure – an intricate lattice – from tiny colloidal particles called triblock Janus spheres.