12-04 :: April/May 2012

nanotimes News in Brief

plasmon resonance scattering light that is captured by a dark-field microscope (DFM). The RGB (three primary colors, red, green, and blue) chrominance information from the dark-field image can be directly converted into the diameters of the GNPs using the relationship between the particle size and the scattering light peak wavelength. © Analytical Che- mistry

Chao Jing, Zhen Gu, Yi-Lun Ying, Da-Wei Li, Lei Zhang, and Yi-Tao Long: Chrominance to Dimension: A Real- Time Method for Measuring the Size of Single Gold Nanoparticles, In: Analytical Chemistry ASAP, April 14, 2012, DOI: 10.1021/ac203118g: http://dx.doi.org/10.1021/ac203118g

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© University of Texas at Austin / R.S. Ruoff research team

Hengxing Ji, Lili Zhang, Michael T. Pettes, Huifeng Li, Shanshan Chen, Li Shi, Richard Piner, and Rodney S. Ruoff: Ultrathin Graphite Foam: A Three-Dimensional Conductive Network for Battery Electrodes, In: Nano Let- ters ASAP, April 23, 2012, DOI:10.1021/nl300528p: http://dx.doi.org/10.1021/nl300528p

Researchers at Department of Mechanical Engi- neering and the Materials Science and Enginee- ring Program, The University of Texas at Austin (US), report in Nano Letters the use of free-stan- ding, lightweight, and highly conductive ultrathin graphite foam (UGF), loaded with lithium iron phosphate (LFP), as a cathode in a lithium ion bat- tery. At a high charge/discharge current density of 1280 mA g–1

on UGF was 70 mAh g–1

, the specific capacity of the LFP loaded , while LFP loaded on Al

foil failed. Accounting for the total mass of the elec- trode, the maximum specific capacity of the UGF/ LFP cathode was 23% higher than that of the Al/ LFP cathode and 170% higher than that of the Ni- foam/LFP cathode. Using UGF, both a higher rate capability and specific capacity can be achieved simultaneously. Moreover, UGF presents excellent electrochemical stability comparing to that of Al and Ni foils. © Nano Letters

Researchers at University of California, USA, University of Bremen, Germany, and Universi- tat Rovira i Virgili, Spain, have developed a novel screening technology that allows large batches of metal-oxide nanomaterials to be assessed quickly, based on their ability to trigger certain bio-logical responses in cells as a result of their semiconduc- tor properties. In a key finding, the research team predicted that metal-oxide nanomaterials and electronically active molecules in the body must have similar electron energy levels – called band- gap energy in the case of the nanomaterial – for this hazardous electron transfer to occur and oxidative damage to result.

Based on this prediction, the researchers screened 24 metal-oxide nanoparticles to determine which were most likely to lead to toxicity under real-life