Picture of the Day

Nano flower

A "Nano Flower," a 3-D nanostructure grown by controlled nucleation of silicon carbide nanowires on gallium catalyst particles. As the growth proceeds, individual nanowires "knit" together to form 3-D structures. This photomicrograph was taken by Ghim Wei Ho, a Ph.D. student studying nanotechnology at the University of Cambridge. Ho--who works with professor Mark Welland, head of Cambridge's Nanoscale Science Lab--makes new types of materials based on nanotechnology (this "Nano Flower" is an example of new material). Nanometer-scale wires (about one thousandth the diameter of a human hair) of a silicon-carbon material (silicon carbide) are grown from tiny droplets of a liquid metal (gallium) on a silicon surface, like the chips inside our home computers. The wires grow as a gas containing methane flows over the surface. The gas reacts at the surface of the droplets and condenses to form the wires. By changing the temperature and pressure of the growth process the wires can be controllably fused together in a natural process to form a range of new structures, including these flower-like materials. Researchers are investigating possible applications for the structures like water repellant coatings and as a base for a new type of solar cell. This image was taken with a scanning electron microscope. Image color was modified using Adobe Photoshop.

Visit Website | Image credit: ©Ghim Wei Ho and Prof. Mark Welland, Nanostructure Center, University of Cambridge