Mario Hofmann of National Cheng Kung University shows the example set up of electrochemical synthesis.
Image: Mario Hofmann/IOP Publishing

Graphene has been affectionately coined the “wonder material” due to its strength, flexibility, and conductive properties. The theoretical applications for graphene have included the five-second phone charge, chemical sensors, a way to soak up environmentally harmful radioactive waste, and even the potential to improve your tennis game. While everyone has big expectations for the wonder material, it’s still struggling to find its place in the world of materials science.

However, a team of researchers may have found a way to expand graphene’s potential and make it more applicable to tangible devices and applications. Through a simple electrochemical approach, researchers have been able to alter graphene’s electrical and mechanical properties.

Technically, the researchers have created a defect in graphene that can make the material more useful in a variety of applications. Through electrochemical synthesis, the team was able to break graphite flakes into graphene layers of various size depending on the level of voltage used.

The different levels of voltage not only changed the material’s thickness, it also altered the flake area and number of defects. With the alternation of these three properties, the researchers were able to change how the material acts in different functions.

“Whilst electrochemistry has been around for a long time it is a powerful tool for nanotechnology because it’s so finely tuneable.” said Mario Hofmann, a researcher at National Cheng Kung University in Taiwan, in a press release. “In graphene production we can really take advantage of this control to produce defects.”

The defected graphene shows promising potential for polymer fillers and battery electrodes. Researchers also believe that by revealing and utilizing the natural defects in graphene, strides could be made in biomedical technology such as drug delivery systems.

The development of ultralight, ultrathin solar cells is on the horizon due to a new semiconductor call phosphorene.

A team of researchers from Australian National University have developed an atom-thick layer of black phosphorus crystals through a process that utilizes sticky tape.

“Because phosphorene is so thin and light, it creates possibilities for making lots of interesting devices, such as LEDs or solar cells,” said lead researcher Dr. Yuerui (Larry) Lu.

The fabrication of this phosphorene is similar to that of graphene, bringing the new material to a thickness of just 0.5 nanometers. With phosphorene’s novel properties, doors are opening for a new generation of solar cells and LEDs.

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Two-dimensional layered structure of graphene and its silicon carbide-free integration with silicon can serve as a prototype in advancing silicon anodes to commercially viable technology.
Source: Nature Communications

Researchers from various institutes across Korea have found a way to nearly double the life of the lithium-ion battery.

In an ever-pressing race to create a more efficient and longer-lasting battery for electronics, researchers across the globe are looking toward alternative materials to make the li-ion battery stronger. A team of researchers associated with Samsung’s Advanced Institute of Technology, including ECS member Jang Wook Choi, have combined silicon and graphene to yield an amazing increase in lithium-ion battery efficiency.

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The topics of climate change and the energy crisis are on the minds of many scientists working in the fields of energy storage and conversion. When looking toward the future, the development of more efficient and effective energy storage technologies is critical. Instead of our traditional “carbon cycle,” researchers are beginning to focus on the “hydrogen cycle” as a promising alternative.

With this, there been a lot of focus on water-splitting techniques. However, there are many challenges that this technology has to overcome before it reaches efficient levels on a large scale.

In order to help address complications associated with water-splitting, ECS member Qiang Zhang is leading a research group from Tsinghua University to help get closer to the ultimate goal of the “hydrogen cycle” by developing a novel graphene/metal hydroxide composite with superior oxygen evolution activity.

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Carbon nanotubes, seamless cylinders of graphene, do not display a total dipole moment. While not zero, the vector-induced moments cancel each other out.
Image: Rice University

Theoretical physicist at both Rice University and institutes in Russia have concluded that the best way to control graphene’s electrical qualities is to flex the material.

Rice University’s Boris Yakobson and his lab are collaborating with Moscow researchers to calculate the electrical properties of nanocones, which should be universal for other forms of graphene.

(PS: You can take a look at some of Yakobson’s past meeting abstracts in the Digital Library.)

This from Rice University:

The researchers discovered it may be possible to access what they call an electronic flexoelectric effect in which the electronic properties of a sheet of graphene can be manipulated simply by twisting it a certain way. The work will be of interest to those considering graphene elements in flexible touchscreens or memories that store bits by controlling electric dipole moments of carbon atoms, the researchers said.

Read the full article here.

“While the dipole moment is zero for flat graphene or cylindrical nanotubes, in between there is a family of cones, actually produced in laboratories, whose dipole moments are significant and scale linearly with cone length,” Yakobson said.

ICYMI: Check out our podcast, “A Word About Nanocarbons,” featuring another Rice University carbon nanotube expert, Dr. Bruce Weisman.

Interested in carbon nanotubes, fullerenes, and nanocarbons? Make sure to check out ECS’s Nanocarbons Division!

One of the world’s strongest natural materials has met one of the strongest artificial materials.

Researchers from the University of Trento, Italy conduced an experiment where they sprayed spiders—producers of naturally strong silk—with carbon-based graphene. Why? Curiosity, of course—the backbone of much great science.

From the experiment, the researchers found that some spiders produced silk that was 3.5 times tougher and stronger than the best naturally produced silk.

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Logan Streu, ECS Content Associate & Assistant to the CCO, recently spotted an article out of Lawrence Livermore National Laboratory detailing a new type of graphene aerogel that could improve energy storage, sensors, nanoelectronics, catalysis, and separations.

The researchers are creating graphene aerogel microlattics through a 3D printing process known as direct ink wetting.

This from Lawrence Livermore National Laboratory:

The 3D printed graphene aerogels have high surface area, excellent electrical conductivity, are lightweight, have mechanical stiffness and exhibit supercompressibility (up to 90 percent compressive strain). In addition, the 3D printed graphene aerogel microlattices show an order of magnitude improvement over bulk graphene materials and much better mass transport.

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When it comes to light bulbs, we’ve seen a lot of transformation since Thomas Edison’s practical incandescent bulb. Since then we’ve delved into fluorescent lights, and more recently, LEDs. Now we’re moving on to the next big thing in light bulbs, and that just may be graphene.

The new bulb is projected to last longer and cut energy use by 10 percent.

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Another possibility for this novel technique is to introduce intentionally imperfections into graphene’s lattice structure to create specific mechanical and electronic attributes.
Image: Nature Communications

A new development out of Caltech could be the first step to producing commercially feasible graphene-based solar cells and LEDs, large-panel displays, and flexible electronics.

“With this new technique, we can grow large sheets of electronic-grade graphene in much less time and at much lower temperatures,” says Caltech staff scientist David Boyd, who developed the method.

While the amazing potential of graphene is universally accepted among the scientific community, scientists have struggled with achieving the properties of the material on an industrially relevant level. The existing techniques either require temperatures that are too hot, or have intrinsic flaws such as deformation of the materials that compromise strength properties.

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Graphene oxide is stable in water and has shown potential in biomedical applications.
Image: Oncotarget

They don’t call it the wonder material for nothing. Since its inception, graphene has shown an amazing array of possibilities – from its potential in renewable resources to its ability to revolutionize electronics. Now, it may even be able to aid in the fight against cancer.

Scientists at the University of Manchester have used graphene to target and neutralize cancer stem cells without harming non-cancerous cells. By taking a modified form of graphene called graphene oxide, the researchers have discovered a quality in the material that acts as an anti-cancer agent that selectively targets cancer stem cells.

The graphene oxide formulations show the potential to treat a broad range of cancers with non-toxic material, including: breast, pancreatic, lung, brain, ovarian, and prostate cancer. The scientist state that if the new treatment were to be combined with existing treatment, it could eventually lead to tumor shrinkage as well as stop the spread of cancer and its reassurance after treatment.

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