Nanoscale & Nanoscale Advances Blog

Recently knighted Sirs Andre Geim and Konstantin Novoselov must feel a bit like The Beatles. Not because they have legions of adoring screaming fans (well, they might, but science isn’t as sexy as rock music), but because you could probably draw parallels between the influences of the Liverpudlian quartet on music and the isolation of graphene on materials science.

Graphenemania doesn’t seem to be abating any time soon either. The latest episode of this incredible craze sees Tian-Ling Ren and his team at Tsinghua University in Beijing taking advantage of single-layer graphene’s (SLG) very low heat capacity per unit area (one of its many remarkable properties) to use it as a sound-emitting material.

Device structure of the grapene "speaker".

The researchers created a device using electrodes deposited onto two ends of a sheet of SLG, which itself is placed on an anodic aluminium oxide substrate. When an electric sound-frequency signal is applied to the graphene, sound is produced through the thermoacoustic effect. In short, when electricity passes through the graphene, the heat produced is transferred to the air around the device surface. The fluctuations in this heat as the current itself fluctuates causes the air to vibrate, producing sound.

Although a previous piece of work has already used graphene in a thin and transparent sound-emitting device, it was merely used as electrodes. Significantly, this is the first time that the material has been demonstrated to actually be able to produce sound itself.

The team found that SLG has a sound pressure level of about 95 dB, which puts it on a par with that experienced when standing a metre from a disco speaker. This makes it ideal for uses such as speakers and earphones, perfect for science’s own ‘Fab Two’ to use to listen to Sergeant Pepper’s Lonely Hearts Club Band.

Read more about this ‘rocking’ new application for graphene here.

Single-layer graphene sound-emitting devices: experiments and modeling
He Tian, Dan Xie, Yi Yang, Tian-Ling Ren, Yu-Feng Wang, Chang-Jian Zhou, Ping-Gang Peng, Li-Gang Wang and Li-Tian Liu
Nanoscale, 2012, DOI: 10.1039/C2NR11572G

We would like to share with you some of the latest exciting research on graphene published in Nanoscale.

You can browse our recent reviews listed below, or read some high impact graphene research papers in our themed collection on graphene.

Nanoscale publishes community-spanning research across the fields of nanoscience and nanotechnology. The journal will get its first full Impact Factor in June 2012 and it’s expected to be very high.

On behalf of the Editors-in-Chief Chunli Bai (NCNST, Beijing), Jie Liu (Duke), Wei Lu (Michigan), Markus Niederberger (ETH Zurich), and Francesco Stellacci (EPFL), we invite you to submit your research today.

Graphene: nanoscale processing and recent applications
László P. Biró, Péter Nemes-Incze and Philippe Lambin
DOI: 10.1039/C1NR11067E

Excitonic properties of graphene-based materials
Min Wang and Chang Ming Li
DOI: 10.1039/C1NR10885A

Inorganic nanostructures grown on graphene layers
Won Il Park, Chul-Ho Lee, Jung Min Lee, Nam-Jung Kim and Gyu-Chul Yi
DOI: 10.1039/C1NR10370A

Graphene edges: a review of their fabrication and characterization
Xiaoting Jia, Jessica Campos-Delgado, Mauricio Terrones, Vincent Meunier and Mildred S. Dresselhaus
DOI: 10.1039/C0NR00600A

2D materials: to graphene and beyond
Rubén Mas-Ballesté, Cristina Gómez-Navarro, Julio Gómez-Herrero and Félix Zamora
DOI: 10.1039/C0NR00323A

Effect of N/B doping on the electronic and field emission properties for carbon nanotubes, carbon nanocones, and graphene nanoribbons
Shan-Sheng Yu and Wei-Tao Zheng
DOI: 10.1039/C0NR00002G

Cu₂ZnSnS₄ nanocrystals and graphene quantum dots for photovoltaics
Jun Wang, Xukai Xin and Zhiqun Lin
DOI: 10.1039/C1NR10425J

Low-toxic and safe nanomaterials by surface-chemical design, carbon nanotubes, fullerenes, metallofullerenes, and graphenes
Liang Yan, Feng Zhao, Shoujian Li, Zhongbo Hu and Yuliang Zhao
DOI: 10.1039/C0NR00647E

Making silica nanoparticle-covered graphene oxide nanohybrids as general building blocks for large-area superhydrophilic coatings
Liang Kou and Chao Gao
DOI: 10.1039/C0NR00609B

Liquid-phase exfoliation, functionalization and applications of graphene
Xu Cui, Chenzhen Zhang, Rui Hao and Yanglong Hou
DOI: 10.1039/C1NR10127G

Why not check out Issue 1 of Nanoscale in 2012 today.

Researchers at Lanzhou University, China, have designed a nanocomposite to effectively remove cadmium ions from human blood.

Previous materials designed for this purpose have either had good selectivity, high saturation magnetisation or good water dispersibility, but the new material has all three properties. And, the composite is highly supermagnetic, making subsequent removal of the nanoparticles easier.

Removing cadmium (which is produced during industrial processes) from the blood is important because they bind to proteins in the body, affecting their functions.

The nanocomposite consists of four components; The first is magnetic iron oxide nanoparticles, chosen for their low toxicity. They are coated with polyethylenimine to increase the amino groups on the particles’ surface to bind Cd²⁺, but also to lower nanoparticle uptake by red blood cells, maximising the circulation time of the composites in the blood. Polyethylene glycol is grafted onto this as an anchor for negatively charged 2,2’-phenylazanediyl, which counteracts the hydrophobic and electrostatic interactions between the nanoparticles and plasma proteins or white blood cells.

Read the Nanoscale article now:

2, 2′-(phenylazanediyl) diacetic acid modified Fe3O4@PEI for selective removal of cadmium ions from blood
Jun Jin, Fang Yang, Fengwei Zhang, Wuquan Hu, Shao-bo Sun and Jiantai Ma
Nanoscale, 2012
DOI: 10.1039/c2nr11481j

HOT Nanoscale Communication

Scientists in China have developed a sensitive method for detecting the bacteria Staphylococcus aureus which is a major cause of food poisoning as well as community- and hospital-acquired infections.

The researchers functionalized gold nanoparticles with phenylboronic acid which could react with the cis-diol groups found on the bacteria’s surface, causing a detectable colour change.

Using this method they could detect the bacteria down to a concentration of 50 cells per mL.

Read the full exciting Nanoscale communication now:

Phenylboronic acid functionalized gold nanoparticles for highly sensitive detection of Staphylococcus aureus
Jine Wang, Jingqing Gao, Dianjun Liu, Dongxue Han and Zhenxin Wang
DOI: 10.1039/C2NR11657J