Tag Archives: nanotechnology

Longer lasting batteries

Posted on by

This is a guest blogpost by Aya Nader.

Using two dimensional oxide anodes with a controlled number of atomic layers is an effective way to prolong the cycle life of Na (sodium) ion batteries, scientists from Saudi Arabia have revealed in a new research. The advancement carries great potential for grid storage.

Batteries normally have two electrodes: anode and cathode. Anodes can be manufactured from different materials, including oxides, sulfides, and phosphides. Usually, oxide anodes such as tin monoxide (SnO) go through massive volume change and degrade significantly after use, seriously shortening the life cycle of a sodium ion battery. Typically, researchers mixed the oxide anodes with carbon-based materials such as graphene to mitigate this large volume change.

“However, the new approach stacks few atomic layers of two dimensional SnO anodes to suppress this volume change, making batteries that last more than 1000 cycles,” explains Husam N. Alshareef, principal investigator of the study and professor of functional nanomaterials and devices at King Abdullah University of Science and Technology (KAUST), Saudi Arabia.

They used two dimensional materials made up of sheets of atoms, or atomic layers, stacked on top of each other. The thinnest SnO nanosheet anodes (two to six SnO monolayers) exhibited the best performance according to their study, published in the journal Nano Letters. As the average number of atomic layers in the anode sheets increased (beyond 10), the battery performance degraded proportionally and remarkably, the study found.

Now, the researchers are trying to combine the SnO anodes with suitable cathode materials to create full cell sodium ion batteries. The idea is to use these batteries to power small devices, such as phones and other electronic devices, and test their cycling performance in more realistic conditions.

In addition, the scientists plan to try charging up the batteries using solar power. Practically, sodium ion batteries are candidates to replace lithium ion batteries, especially in stationary storage applications, as sodium is cheaper and more available than lithium.

“Our progress using SnO anodes has resulted in stable sodium ion batteries that offer competitive capacity for grid scale applications,” says Fan Zhang, PhD researcher and lead author of the study. “This is exciting because it means a more effective storage solution has been identified for grid storage applications.”

In the classroom: Creativity unleashed

Posted on by
Reply

A few building blocks is all it takes to stimulate scientific curiosity in students, says François Grey.

Nature-nanotechnologyMany will agree that academic hands-on projects are more effective than long lectures in enticing students’ interest. A practical approach is best suited in particular for interdisciplinary subjects such as nanotechnology, and can help breaking the ice between fellow students in a classroom, and foster learning. In our May issue of In the classroom, François Grey tells us how he has used a hands-on approach to engage students of the summer school LEGO2NANO, held annually at Tsinghua University, in learning about nanotechnology. He challenged student teams to come up, in a week time, with a prototype atomic force microscope that could be used in Chinese schools – with a maximum budget of US$1000.  Lego blocks were used among other cheap components, and students were inspired to develop their creative skills. On the back of the success of LEGO2NANO, François is also involved in the launch of a more permanent initiative, called Lifelong Learning Lab, aimed at fostering creativity in the classroom.

Read François Grey’s article, Creativity unleashed, for free on the Nature Nano website.

In the classroom: From nano to micro and back

Posted on by
Reply

Working in large collaborations can help you understand how nanotechnology is closely related to other fields.

Nature-nanotechnology

When studying nanotechnology it is common to learn that structures with nanoscale dimensions have unique physical and chemical properties, which differentiate them from particles of bigger sizes. But things are not always as disconnected as they may seem. While working on the synthesis of microbubbles to be used as multimodal contrast agent, Elizabeth Huynh discovered that nanoparticles formed by the destruction of her porphyrin particles of micrometre size by ultrasound would retain some of properties of the larger structures. Most importantly she came to her conclusions after intensive collaboration with colleagues with different expertise, showing her that nanotechnology cannot really work as isolated discipline.

Read Elizabeth Huynh’s article going from nano to micro and back on Nature Nanotechnology for free.

Research strategy urged on risks of nanotechnology

Posted on by
Reply

A selection of CosmeticsCalls for high-quality research into the risks of nanotechnology date back as far as the field itself,  but now one august body has added its voice. In a report released today the US National Academy of Sciences (NAS) calls for a more coordinated research strategy to cover open questions as basic as how many nanoparticles of different kinds are being released into the environment, and who is being exposed to them. “There are some significant gaps that we need to address in order to move forward,” says Rebecca Klaper, an ecologist at the University of Wisconsin-Milwaukee who served on the authoring committee.

The report also criticizes the US National Nanotechnology Initiative (NNI), which since 2000 has coordinated operations at the many US agencies that fund nanomaterials-risks research, focusing on the NNI’s dual role in promoting nanotechnology while also overseeing research on its risks. Klaper says that the NNI was founded to promote job creation in industries that use nanotechnology, such as cosmetics and car manufacturing. “There’s a potential conflict,” she says. The NAS panel is urging that the promotional activity be separated from the oversight of research into risks. It also says the NNI needs additional budgetary authority to shepherd some of the US$120 million that the US now spends piecemeal on nanomaterials-risk research in a larger, better coordinated effort. Research would also benefit from a small funding increase of around $22 million–$24 million per year, the panel says.

A spokeswoman for NNI says, “we see no inherent conflict of interest in the NNI’s focus on the responsible development of nanotechnology.” She adds that the NNI believes the current approach to shared budgetary responsibilities has been very effective and that the new authority recommended by the report would require action by the US Congress.

A report issued by the NNI in 2011 released a research strategy for nanotechnology but the NAS did not look at that as part of its study, which the spokeswoman says is unfortunate, as the NNI has already covered many of the elements the study calls for.

In December, Nature reported on concerns over the standards and quality of the nanotoxicology literature. As did the experts quoted in that story, the NAS called for accelerated development of standard reference materials so that researchers can calibrate the materials they are testing relative to one another.

Image by incurable_hippie on Flickr under Creative Commons.

DNA origami on the rise

Posted on by
Reply

Nanotechnology is all the rage these days but its use by practicing biologists is still very limited. A recent entry in the nanotechnology arena is DNA origami, a method for creating nanostructures out of DNA that is more accessible than previous methods and allows larger and more complex structures to be created with greater ease.

In the April issue of Nature Methods you will find a primer to DNA origami that provides an excellent introduction to this technology with valuable practical advice on designing and synthesizing DNA nanostructures using the DNA origami methodology. We hope that this primer will stimulate biologists or others new to this field to take a look at this technology and dream up exciting new applications.

One of the crucial steps of DNA origami is isolating your properly folded structure. A Correspondence by William Shih, one of the pioneers of DNA origami, describes some simple but very useful modifications to an agarose gel electroelution method that many people use for isolating PCR products or small DNA fragments from restriction digests. These changes greatly increase the efficiency of isolating intact large DNA nanostructures compared to existing methods.

Finally, the Editorial discusses the prospects of DNA nanostructures created using DNA origami as biological research tools.

Based on the number of posters describing applications of DNA origami at the 2010 Gordon Research Conference on Single Molecule Approaches to Cell Biology, compared to previous years the biological community and the single molecule biophysics community in particular is showing interest in the methodology. Only time will tell if it fairs better among biologists than other promising nanotechnology tools and methods.

We’d like to know what our readers think of the biological research prospects of this technology, or other nanotechnology tools and methods for that matter. Tell us what you think.