10-04 :: April 2010
News in Brief
in the creation of bubbles throughout the core. The “skeletons” of those bub- bles still remained, even after full oxidation, crea- ting an essentially hollow shell that was still criss- crossed with some remnants of the nickel core.
“This tells us a lot about how to create nanoscale structures using the nanoscale Kirkendall Effect,” Tracy says. “It’s a building block for future research in the field.”
Justin G. Railsback, Aaron C. Johnston-Peck, Junwei Wang and Joseph B. Tracy: Size-Dependent Nanoscale Kirkendall Effect During the Oxidation of Nickel Nanoparticles, In: ACS Nano AOP, April 2, 2010, DOI:10.1021/nn901736y: http://dx.doi.org/10.1021/nn901736y
Image of a half-oxidized 26 nanometer nanoparticle. The nickel region is colored red, and the nickel oxide is colo- red blue and green. © ACS Nano
Graphene Sheets //
Closing In On A Carbon-based Solar Cell
o make large sheets of carbon available for
light collection, Indiana University Blooming-
ton chemists have devised an unusual solution – attach what amounts to a 3-D bramble patch to each side of the carbon sheet. Using that method, the
scientists say they were able to dissolve sheets con- taining as many as 168 carbon atoms, a first.
“Our interest stems from wanting to find an alter- native, readily available material that can efficiently absorb sunlight,” said chemist Liang-shi Li, who led the research. “At the moment the most common materials for absorbing light in solar cells are silicon
Image: This is a 2-D view of a graphene sheet (black) and attached sidegroups (blue) that IU Bloomington chemist Liang-shi Li and his collaborators devised. In reality, each sidegroup rotates 90 degrees or so out of graphene‘s pla- ne. The three blue, tail-like hydrocarbons of each side- group have great freedom of movement, but two are likely to hover over the graphene, making it very unlikely that one graphene sheet will touch another. © Liang-shi Li