Graphene 2.0 - p517

doi:10.1038/nnano.2008.253

Once the preserve of physicists, graphene is now attracting the attention of growing numbers of chemists, who are discovering new ways to produce this remarkable material.

Full Text - Graphene 2.0 | PDF (130 KB) - Graphene 2.0

Subject Categories: Carbon nanotubes and fullerenes | Nanomaterials | Synthesis and processing

Questions and answers - pp519 - 520

Chris Toumey

doi:10.1038/nnano.2008.256

There are many different ways to introduce the public to nanotechnology, writes Chris Toumey. Just don't mention human hairs or the space elevator.

Full Text - Questions and answers | PDF (194 KB) - Questions and answers

Subject Category: Ethical, legal and other societal issues

DNA nanotubes with programmable circumferences, structures from ice moulds, the strongest material ever measured, explosive gold nanoparticles, and more - pp522 - 523

doi:10.1038/nnano.2008.257

Full Text - DNA nanotubes with programmable circumferences, structures from ice moulds, the strongest material ever measured, explosive gold nanoparticles, and more | PDF (270 KB) - DNA nanotubes with programmable circumferences, structures from ice moulds, the strongest material ever measured, explosive gold nanoparticles, and more

Top down bottom up: Commercial graphene - p523

doi:10.1038/nnano.2008.258

Researchers have set up a company to sell graphene samples to other researchers.

Full Text - Top down bottom up: Commercial graphene | PDF (150 KB) - Top down bottom up: Commercial graphene

Subject Categories: Carbon nanotubes and fullerenes | Industry and IPR

Mass sensors: Weighing single atoms with a nanotube - pp525 - 526

Robert G. Knobel

doi:10.1038/nnano.2008.250

Researchers have used a vibrating carbon nanotube to set a new record for nanomechanical mass sensing. Could this approach — currently being pursued by three independent groups — lead to a new type of mass spectrometer?

Full Text - Mass sensorsWeighing single atoms with a nanotube | PDF (388 KB) - Mass sensorsWeighing single atoms with a nanotube

Subject Categories: Carbon nanotubes and fullerenes | Nanometrology and instrumentation | NEMS

Patterned surfaces: An organized union - p526

Owain Vaughan

doi:10.1038/nnano.2008.247

Full Text - Patterned surfacesAn organized union | PDF (220 KB) - Patterned surfacesAn organized union

Subject Categories: Molecular self-assembly | Surface patterning and imaging

Nanomaterials: Nano-selenium captures mercury - pp527 - 528

Nicholas Ralston

doi:10.1038/nnano.2008.251

Nanoscale formulations of selenium can effectively capture mercury vapours from spills that could otherwise contaminate the air of homes and offices.

Full Text - NanomaterialsNano-selenium captures mercury | PDF (216 KB) - NanomaterialsNano-selenium captures mercury

Subject Categories: Nanomaterials | Environmental, health and safety issues

Graphene production: New solutions to a new problem - pp528 - 529

Jun Zhu

doi:10.1038/nnano.2008.249

Two independent teams have shown that it is possible to produce stable suspensions of single-layer graphene from graphite crystals using chemical techniques.

Full Text - Graphene productionNew solutions to a new problem | PDF (147 KB) - Graphene productionNew solutions to a new problem

Subject Categories: Nanomaterials | Synthesis and processing

Molecular logic: Monolayers with an IQ - pp529 - 530

Alberto Credi

doi:10.1038/nnano.2008.252

Thin films of redox-active molecules can be used to construct logic gates, which can then be linked together to create basic circuits.

Full Text - Molecular logicMonolayers with an IQ | PDF (344 KB) - Molecular logicMonolayers with an IQ

Subject Categories: Molecular machines and motors | Nanosensors and other devices

Molecular motors: Keep on moving - pp531 - 532

Kazuhiro Oiwa & Hiroaki Kojima

doi:10.1038/nnano.2008.248

Large cargos stop protein filaments from rotating as they glide along a surface coated with motor proteins, but small cargos do not.

Full Text - Molecular motorsKeep on moving | PDF (689 KB) - Molecular motorsKeep on moving

Subject Categories: Molecular machines and motors | Surface patterning and imaging

An atomic-resolution nanomechanical mass sensor - pp533 - 537

K. Jensen, Kwanpyo Kim & A. Zettl

doi:10.1038/nnano.2008.200

Nanoscale mechanical resonators can make precision measurements of force, position and mass. Atomic resolution in mass sensing at room temperature has now been demonstrated with a carbon nanotube-based resonator that essentially operates as a mass spectrometer. The atomic equivalent of shot noise has also been detected.

Abstract - | Full Text - An atomic-resolution nanomechanical mass sensor | PDF (403 KB) - An atomic-resolution nanomechanical mass sensor | Supplementary information

Subject Categories: Carbon nanotubes and fullerenes | Nanometrology and instrumentation | NEMS

See also: News and Views by Knobel

Highly conducting graphene sheets and Langmuir–Blodgett films - pp538 - 542

Xiaolin Li, Guangyu Zhang, Xuedong Bai, Xiaoming Sun, Xinran Wang, Enge Wang & Hongjie Dai

doi:10.1038/nnano.2008.210

The first samples of pristine graphene were obtained by 'peeling off' and epitaxial growth, but chemical approaches are more suited to large-scale production. Exfoliation, reintercalation and expansion of graphite can produce high-quality single-layer graphene sheets suspended in organic solvents, and these sheets can be made into large transparent films by Langmuir–Blodgett assembly.

Abstract - | Full Text - Highly conducting graphene sheets and Langmuir–Blodgett films | PDF (414 KB) - Highly conducting graphene sheets and Langmuir–Blodgett films | Supplementary information

Subject Categories: Nanomaterials | Synthesis and processing

See also: News and Views by Zhu

Nanoparticle-assisted high photoconductive gain in composites of polymer and fullerene - pp543 - 547

Hsiang-Yu Chen, Michael K. F. Lo, Guanwen Yang, Harold G. Monbouquette & Yang Yang

doi:10.1038/nnano.2008.206

The performance of state-of-the-art photovoltaic devices based on polymer–nanocrystal composites is still limited by the preparation of the composite films. By blending and annealing cadmium telluride nanocrystals in a polymer–fullerene matrix, high photoconductive gain can be achieved under low applied voltages.

Abstract - | Full Text - Nanoparticle-assisted high photoconductive gain in composites of polymer and fullerene | PDF (465 KB) - Nanoparticle-assisted high photoconductive gain in composites of polymer and fullerene | Supplementary information

Subject Categories: Electronic properties and devices | Nanosensors and other devices | Organic-inorganic nanostructures

Control of enhanced Raman scattering using a DNA-based assembly process of dye-coded nanoparticles - pp548 - 551

Duncan Graham, David G. Thompson, W. Ewen Smith & Karen Faulds

doi:10.1038/nnano.2008.189

Base-pairing drives the assembly of dye-functionalized nanoparticles that have complementary DNA strands attached. This aggregation leads to a massive enhancement of the resonant Raman signal, which may prove useful for sensing applications.

Abstract - | Full Text - Control of enhanced Raman scattering using a DNA-based assembly process of dye-coded nanoparticles | PDF (233 KB) - Control of enhanced Raman scattering using a DNA-based assembly process of dye-coded nanoparticles | Supplementary information

Subject Categories: Molecular self-assembly | Nanoparticles | Nanosensors and other devices

Quantum-dot-assisted characterization of microtubule rotations during cargo transport - pp552 - 556

Bert Nitzsche, Felix Ruhnow & Stefan Diez

doi:10.1038/nnano.2008.216

A combination of quantum dots and fluorescence-interference contrast microscopy can be used to monitor the rotation of microtubules with nanometre accuracy as they glide over motor proteins. This approach shows that the microtubules stop rotating when they pick up large cargos, but their velocity does not change.

Abstract - | Full Text - Quantum-dot-assisted characterization of microtubule rotations during cargo transport | PDF (541 KB) - Quantum-dot-assisted characterization of microtubule rotations during cargo transport | Supplementary information

Subject Categories: Molecular machines and motors | Surface patterning and imaging

See also: News and Views by Oiwa & Kojima

Carbon nanotubes as photoacoustic molecular imaging agents in living mice - pp557 - 562

Adam De La Zerda, Cristina Zavaleta, Shay Keren, Srikant Vaithilingam, Sunil Bodapati, Zhuang Liu, Jelena Levi, Bryan R. Smith, Te-Jen Ma, Omer Oralkan, Zhen Cheng, Xiaoyuan Chen, Hongjie Dai, Butrus T. Khuri-Yakub & Sanjiv S. Gambhir

doi:10.1038/nnano.2008.231

Photoacoustic imaging offers higher spatial resolution than most optical imaging techniques, but contrast agents are needed because many diseases in their early stages do not display a natural photoacoustic contrast. Using single-walled carbon nanotubes conjugated with a peptide as a contrast agent allows the non-invasive photoacoustic imaging of tumours in animals.

Abstract - | Full Text - Carbon nanotubes as photoacoustic molecular imaging agents in living mice | PDF (473 KB) - Carbon nanotubes as photoacoustic molecular imaging agents in living mice | Supplementary information

Subject Categories: Carbon nanotubes and fullerenes | Surface patterning and imaging

High-yield production of graphene by liquid-phase exfoliation of graphite - pp563 - 568

Yenny Hernandez, Valeria Nicolosi, Mustafa Lotya, Fiona M. Blighe, Zhenyu Sun, Sukanta De, I. T. McGovern, Brendan Holland, Michele Byrne, Yurii K. Gun'Ko, John J. Boland, Peter Niraj, Georg Duesberg, Satheesh Krishnamurthy, Robbie Goodhue, John Hutchison, Vittorio Scardaci, Andrea C. Ferrari & Jonathan N. Coleman

doi:10.1038/nnano.2008.215

Fully exploiting the properties of graphene will require a method for the mass production of this remarkable material. The dispersion and exfoliation of graphite in organic solvents can produce graphene monolayers with a yield of about 1% by weight. Moreover, these samples are free from defects and oxides, and can be used to produce semi-transparent conducting films and conducting composites.

Abstract - | Full Text - High-yield production of graphene by liquid-phase exfoliation of graphite | PDF (650 KB) - High-yield production of graphene by liquid-phase exfoliation of graphite | Supplementary information

Subject Categories: Nanomaterials | Synthesis and processing

Molecular junctions based on aromatic coupling - pp569 - 574

Songmei Wu, Maria Teresa González, Roman Huber, Sergio Grunder, Marcel Mayor, Christian Schönenberger & Michel Calame

doi:10.1038/nnano.2008.237

Experiments to explore electron transport in single molecules generally involve the use of chemical linker groups at both ends of the molecule to firmly anchor it to the source and drain contacts. Here it is shown that oligo-phenylene ethynylene molecules with a single anchor group can form molecular junctions as well. The process is attributed to aromatic stacking between neighbouring molecules in nearby electrodes.

Abstract - | Full Text - Molecular junctions based on aromatic coupling | PDF (487 KB) - Molecular junctions based on aromatic coupling | Supplementary information

Subject Category: Electronic properties and devices