Researchers Develop Nanoblade

Sep 25, 2007
Researchers Develop Nanoblade
A view of new nanoblades from above. Photo Credit: Rensselaer/ Tom Parker

Researchers at Rensselaer Polytechnic Institute have created a razor-like material that is truly on the “cutting edge” of nanotechnology. Called nanoblades, these first-of-their-kind magnesium nanomaterials challenge conventional wisdom about nanostructure growth, and could have applications in energy storage and fuel cell technology.

The discovery is detailed in the September 2007 issue of the Journal of Nanoscience and Nanotechnology.

The sharp nanometer-scale surface is vastly different from any other nanomaterial that has been created before using oblique angle deposition, according to lead researcher Gwo-Ching Wang, professor and head of physics, applied physics, and astronomy at Rensselaer. The team’s nearly two-dimensional structure changes the traditional understanding of oblique angle deposition, which was previously thought to always create cylindrical structures like nanorods or nanosprings.

Unlike three-dimensional springs and rods, nanoblades are extremely thin, with very large surface areas. They also are surprisingly spread out for a uniform nanomaterial, with one to two micron meters in between each blade, according to Wang.

The materials could be extremely useful for energy storage, particularly hydrogen storage, Wang said. In order to store hydrogen, a large surface area is needed to provide room for the material to expand as more hydrogen atoms are stored. The vast surface area of each nanoblade, coupled with the large spaces between each blade, could make them ideal for this application.

To create the nanoblades, the researchers used oblique angle vapor deposition. This widely used fabrication technique builds nanostructures by vaporizing a material — magnesium in this case — and allowing the vaporized atoms to deposit on a surface at an angle. As the deposition angle changes, the structure of the material deposited on the surface also changes.

When the researchers deposited the magnesium straight onto a surface at zero degrees, the blades resembled a handful of cornflakes — flat, flakey structures overlapping one another. It wasn’t until the deposition angle was increased that the blade-like nature of these new nanomaterials became apparent.

As the magnesium deposition angle was increased, the researchers were surprised that the structures first tilted away from the magnesium vapor source instead of the expected inclination toward the source. The blades then quickly curved upward to form nearly vertical structures resembling nano-scale razorblades.

The blades also become ultra thin. From the side, the nanoblades resemble an overgrown lawn with thin, blade-like spires. At a 75 degree angle, the nanoblades had a thickness of as little as 15 nanometers and a width of a few hundred nanometers.

Researchers at Rensselaer are now looking at ways to coat the magnesium nanoblades with metallic catalysts to trap and store hydrogen.

The researchers monitored the blades as they were growing using a reflection high-energy electron diffraction (RHEED) technique to create a surface pole figure or image. The new technique, created at Rensselaer, is different from other diffraction techniques such as X-rays because it monitors the surface structure of the material as it grows. X-rays and other technologies measure the entire material, from the tip of the new growth straight through the substrate that the material is growing on.

Tracking the surface evolution of the material provides insight into how the structure evolves over time and helps scientists understand the mechanism of nanostructure formation, allowing engineers to later recreate ideal nanomaterials in the future. The creation of surface pole figures was particularly important in understanding the growth of nanoblades, as the surface morphology changed vastly over time.

The surface pole figure technique was first outline by Fu Tang, a postdoctoral research associate in Wang’s group, in a 2006 issue of Applied Physics Letters. In that paper, surface pole figures were created for nanorod growth. The researchers are now working to analyze nanoblade growth to provide additional insight into the growth patterns of these new nanomaterials.

Other Rensselaer researchers involved with the project are Toh-Ming Lu, the R.P. Baker Distinguished Professor of Physics; GAANN fellow Tom Parker; and postdoctoral research associate Huafang Li.

Source: Rensselaer Polytechnic Institute

Explore further: Project uses crowd computing to improve water filtration

Related Stories

Trapping vortices key to high-current superconductors

Jul 02, 2015

If we are to see the promised benefits of high-temperature superconductors, such as low-loss motors and generators or maglev trains, we will need superconductors that can carry very large currents.

Self-assembly of molecular Archimedean polyhedra

Jul 01, 2015

Chemists truly went back to the drawing board to develop new X-shaped organic building blocks that can be linked together by metal ions to form an Archimedean cuboctahedron. In the journal Angewandte Chemie, the sc ...

Rosetta spacecraft sees sinkholes on comet

Jul 01, 2015

The European Space Agency's Rosetta spacecraft first began orbiting comet 67P/Churyumov-Gerasimenko in August 2014. Almost immediately, scientists began to wonder about several surprisingly deep, almost perfectly ...

Substrates change nanoparticle reactivity

Jun 30, 2015

(Phys.org)—Nanoscale materials tend to behave differently than their bulk counterparts. While there are many theories as to why this happens, technological advances in scanning tunneling microscopy (STM) ...

Exposed water ice detected on comet's surface

Jun 25, 2015

Using the high-resolution science camera on board ESA's Rosetta spacecraft, scientists have identified more than a hundred patches of water ice a few metres in size on the surface of Comet 67P/Churyumov-Gerasimenko.

Recommended for you

Tiny wires could provide a big energy boost

3 hours ago

Wearable electronic devices for health and fitness monitoring are a rapidly growing area of consumer electronics; one of their biggest limitations is the capacity of their tiny batteries to deliver enough ...

Graphene sheets enable ultrasound transmitters

3 hours ago

University of California, Berkeley, physicists have used graphene to build lightweight ultrasonic loudspeakers and microphones, enabling people to mimic bats or dolphins' ability to use sound to communicate ...

Project uses crowd computing to improve water filtration

21 hours ago

Nearly 800 million people worldwide don't have access to safe drinking water, and some 2.5 billion people live in precariously unsanitary conditions, according to the Centers for Disease Control and Prevention. ...

Engineering the world's smallest nanocrystal

Jul 06, 2015

In the natural world, proteins use the process of biomineralization to incorporate metallic elements into tissues, using it to create diverse materials such as seashells, teeth, and bones. However, the way ...

A stretchy mesh heater for sore muscles

Jul 03, 2015

If you suffer from chronic muscle pain a doctor will likely recommend for you to apply heat to the injury. But how do you effectively wrap that heat around a joint? Korean Scientists at the Center for Nanoparticle ...

Polymer mold makes perfect silicon nanostructures

Jul 03, 2015

Using molds to shape things is as old as humanity. In the Bronze Age, the copper-tin alloy was melted and cast into weapons in ceramic molds. Today, injection and extrusion molding shape hot liquids into ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.