By: Mike Williams, Rice University

Rice University researchers have modeled a nanoscale sandwich, the first in what they hope will become a molecular deli for materials scientists.

Their recipe puts two slices of atom-thick graphene around nanoclusters of magnesium oxide that give the super-strong, conductive material expanded optoelectronic properties.

Rice materials scientist Rouzbeh Shahsavari and his colleagues built computer simulations of the compound and found it would offer features suitable for sensitive molecular sensing, catalysis and bio-imaging. Their work could help researchers design a range of customizable hybrids of two- and three-dimensional structures with encapsulated molecules, Shahsavari said.

The research appears this month in the Royal Society of Chemistry journal Nanoscale.

The scientists were inspired by experiments elsewhere in which various molecules were encapsulated using van der Waals forces to draw components together. The Rice-led study was the first to take a theoretical approach to defining the electronic and optical properties of one of those “made” samples, two-dimensional magnesium oxide in bilayer graphene, Shahsavari said.

“We knew if there was an experiment already performed, we would have a great reference point that would make it easier to verify our computations, thus allowing more reliable expansion of our computational results to identify performance trends beyond the reach of experiments,” Shahsavari said.

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By using one of the world’s most powerful electron microscopes, a team of researchers from Lawrence Berkeley National Laboratory has successfully mapped the exact location and chemical type of 23,000 atoms in a nanoparticle made of iron and platinum. The team believes this work could reveal more information about material properties at the single-atom level, opening the doors to improving magnetic performance for next-generation hard drives.

“Our research is a big step in this direction. We can now take a snapshot that shows the positions of all the atoms in a nanoparticle at a specific point in its growth,” says Mary Scott, who conducted the research. “This will help us learn how nanoparticles grow atom by atom, and it sets the stage for a materials-design approach starting from the smallest building blocks.”

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Overheating has emerged as a primary concern in the development of new electronic devices. A new study from Rice University looks to provide a solution to that, offering a strategy to vent heat away from nano-electronics through cone-like chimneys.

By putting these “chimneys” between the graphene and nanotube, the researchers effectively eliminate a barrier that typically blocks heat from escaping.

This from Rice University:

Researchers at Rice University discovered through computer simulations that removing atoms here and there from the two-dimensional graphene base would force a cone to form between the graphene and the nanotube. The geometric properties of the graphene-to-cone and cone-to-nanotube transitions require the same total number of heptagons, but they are more sparsely spaced and leave a clear path of hexagons available for heat to race up the chimney.

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One of the major challenges in modern medicine is how to accurately detect disease when people are still feeling healthy. Researchers and doctors alike have long since wondered how to diagnose diseases such as cancer before it progresses too far.

Now, the medical community may find that answer in a new development out of Technion – Israel Institute of Technology called the Na-Nose.

The Na-Nose is a newly developed device that can analyze the chemical signature of exhaled gases to diagnose diseases with 86 percent accuracy. The science behind the device uses carbon nanotubes and gold particles to isolate volatile biomarkers in a patient’s breath.

Researchers then used a computer algorithm to recognize the biomarkers, creating a tool that can quickly and accurately detect diseases such as ovarian cancer or multiple sclerosis in early stages without any invasive procedures.

“It works in the same way we’d use dogs in order to detect specific compounds,” Hossam Haick, co-author of the study, told Smithsonian. “We bring something to the nose of a dog, and the dog will transfer that chemical mixture to an electrical signature and provide it to the brain, and then memorize it in specific regions of the brain … This is exactly what we do. We let it smell a given disease but instead of a nose we use chemical sensors, and instead of the brain we use the algorithms. Then in the future, it can recognize the disease as a dog might recognize a scent.”

By: Sameer Sonkusale, Tufts University

Doctors have various ways to assess your health. For example, they measure your heart rate and blood pressure to indirectly assess your heart function, or straightforwardly test a blood sample for iron content to diagnose anemia. But there are plenty of situations in which that sort of monitoring just isn’t possible.

To test the health of muscle and bone in contact with a hip replacement, for example, requires a complicated – and expensive – procedure. And if problems are found, it’s often too late to truly fix them. The same is true when dealing with deep wounds or internal incisions from surgery.

In my engineering lab at Tufts University, we asked ourselves whether we could make sensors that could be seamlessly embedded in body tissue or organs – and yet could communicate to monitors outside the body in real time. The first concern, of course, would be to make sure that the materials wouldn’t cause infection or an immune response from the body. The sensors would also need to match the mechanical properties of the body part they would be embedded in: soft for organs and stretchable for muscle. And, ideally, they would be relatively inexpensive to make in large quantities.

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A giant among giants

Harry Kroto, distinguished chemist and pioneering nanocarbons researcher, passed away on April 30, 2016 at the age of 76. Kroto, a giant among giants, made an immense impact not only on ECS and its scientific discipline – but the world at large.

“Harry Kroto’s passing is a great loss to science and society as a whole,” says Bruce Weisman, professor at Rice University and division chair of the ECS Nanocarbons Division. “He was an exceptional researcher whose 1985 work with Rick Smalley and Bob Curl launched the field of nanocarbons research and nanotechnology.”

Revolutionizing chemistry

That work conducted by Kroto, Smalley, and Curl yielded the discovery of the C60 structure that became known as the buckminsterfullerene (or the “buckyball” for short). Prior to this breakthrough, there were only two known forms of pure carbon: graphite and diamond. The work opened a new branch in chemistry with unbound possibilities, earning the scientists the 1996 Nobel Prize in Chemistry.

The field of nanocarbons and fullerenes, since the discovery by Kroto and company, has evolved into an area with almost limitless potential. The applications for this scientific discipline are wide-ranging – from energy harvesting to sensing and biosensing to biomedical applications and far beyond. Research in this field continues to fill the pages of scholarly journals, making possible innovations that were not even conceived before the seminal 1985 work.

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Nanoparticles have been central to many recent developments, including computing, communications, energy, and biology. However, because nanoparticles are hard to observe, it’s often difficult to pick the best shapes and sizes to perform specific tasks at optimal capacity.

That may be a problem no longer thanks to research out of Stanford University, where researchers gazed inside phase-changing nanoparticles for the first time – allowing them to understand how shape and crystallinity can have dramatic effects on performance.

Practically, this means that the design of energy storage materials could begin to change.

Take the lithium-ion battery, which stores and releases energy due to the electrode’s ability to sustain large deformations over several charge and discharge cycles without degrading. By nanosizing the electrode, researchers recently improved upon the efficiency process.

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Oil spills have had an extensive history of disrupting the environment, killing ecosystems, and displacing families. Impacts of massive oil spills are still felt in many parts of the world, including the undersea spill at the BP oil rig in the Gulf of Mexico that dumped an approximate 39 million gallons of oil into the gulf.

But what if these devastating oil spills could be easily cleaned up with a piece of fabric rooted in electrochemistry?

That may be a reality soon thanks to researchers at Queensland University of Technology (QUT). According to a release, the QUT researchers have developed a multipurpose fabric covered with semi-conducting nanostructures that can both mop up oil and degrade organic matter when exposed to light.

(READ: “Superhydrophobic Fabrics for Oil/Water Separation Based on the Metal-Organic Charge-Transfer Complex CuTCNAQ“)

The fabric, which repels water and attracts oil, has already has promising preliminary results. In the early stages of research, the scientists have already been able to mop up crude oil from the surface of both fresh and salt water.

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Artificial limbs have experience tremendous evolution in their long history. Throughout history, we’ve gone from the peg leg of the Dark Ages to technologically advanced modern day prosthesis that mimic the function of a natural limb. However, most prosthesis still lack a sense of touch.

Zhenan Bao, past ECS member and chemical engineer at Stanford University, is at the forefront of the research looking to change that.

(MORE: Read Bao’s past meeting abstracts in the ECS Digital Library for free.)

Recently on NPR’s All Things Considered, Bao described her work in developing a plastic artificial skin that can essentially do all the things organic skin can do, including sensing and self-healing.

The self-healing plastic Bao uses mimics the electrical properties of silicon and contains a nano-scale pressure sensor. The sensor is then connected to electrical circuits that connect to the brain, transmitting the pressure to the brain to analyze as feeling.

Additionally, the skin is set to be powered by polymers that can turn light into electricity.

While there is still much work to be done, Bao and her colleagues believe that this product could help people who have lost their limbs regain their sense of touch.

A research team, including ECS members Stephen Doorn and Erik H Hároz, has created flexible, wafer-scale films of highly aligned and closely packed carbon nanotubes thanks to a simple filtration process. In a discovery that was previously though impossible, the researchers found that in the right solution and under the right conditions, the tubes can assemble themselves by the millions into long rows.

(ICYMI: Get the freshman 101 on carbon nanotubes from nanocarbons expert Bruce Weisman.)

This development could help bring flexible electronics to actuality, especially with the special electronic properties of the nanotubes.

“Once we have centimeter-sized crystals consisting of single-chirality nanotubes, that’s it,” said Junichiro Kono, Rice University physicist leading the study. “That’s the holy grail for this field. For the last 20 years, people have been looking for this.”