Nanotechnology

Secret Garden 

                Courtesy of Ghim Wei Ho/Professor Mark Welland/Nanoscience Centre/University of Cambridge

Nanotechnology, the science of the ultra-small, just got a lot prettier. Ghim Wei Ho, a graduate student at Cambridge University, has created a garden of nanoflowers (above), lifelike bouquets of silicon carbide whose individual “blooms” span just one-thousandth the diameter of a human hair. Ho and her colleagues created these delicate structures by attaching droplets of liquid gallium to tiny silicon wires and immersing them in a gas containing methane. As the gas flowed over the droplets, it prompted the growth of intertwining filaments of silicon carbide. “We expected nanostructures, but the beauty and complexity of the actual formations was really exciting,” says Mark Welland, Ho’s adviser and the director of Cambridge’s Nanoscale Science Laboratory.

Beyond visual appeal, nanoflowers may be useful as water repellents that can be turned on or off by an external stimulus such as a temperature change, which might benefit many industrial processes. When combined with other polymers, the structures could also convert light into electricity and serve as the basis for a novel type of solar cell. “We are creating a whole range of shapes,” Welland says. “There will certainly be further applications as we increase our understanding of these strange new materials.”