"Flower Bouquet," 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. 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 these structures, such as water repellant coatings and as a base for a new type of solar cell.
Image credit: ©Ghim Wei Ho and Prof. Mark Welland, Nanostructure Center, University of Cambridge