Monday, June 2, 2014

Graphene leads to super-efficient batteries

Graphene and the many shapes it can
be made into

Emissions from fossil fuels, known as greenhouse gases, are one of our biggest enemies. In addition to the pollution in the air, ground, and water from our desperate efforts to get more, much of our infrastructure created by these same fossil fuels hangs in the balance. One of the largest threats posed by this change in temperature is sea level rise; many cities in the U.S. such as New York, Miami, Boston, Los Angeles, and Seattle will be underwater in the next 100 years if the climate-change induced warming of glaciers continues, as will many more coastal cities all over the world.

Where are these emissions coming from? More than a quarter of it is produced by transportation. When broken down into the most common modes of transportation, air, rail, road, and water, road transportation is not only the largest offender but is also has the simplest solution in sight. Fairly efficient electric cars are already being developed and are being developed well, with the Tesla Model S being selected by Consumer Reports as the “Best Overall Car” of 2014. Electric cars remove the dependence on fossil fuels from car owners and instead pulls energy from the grid. This means that as power companies switch to renewable energy sources, so do the cars, solving two problems at once. Despite the electric car’s recent appeal, they are being held back by one thing: the battery.

The battery of the tesla Model S, a luxury sedan costing ~$70,000, lasts for an optimal 265 miles on a charge. Under perfect conditions, this charge can be completed with a wall socket in just under 40 hours, a wait far too long for many, especially for that price tag. The more affordable Nissan Leaf only has a driving range of about 70 miles, making it even more impractical for the average commuter. The solution to this problem may lie in the combination of an existing battery technology with a new nanomaterial. Lithium-sulfur batteries can hold more than four times the amount of energy than the currently popular lithium-ion batteries, and their effectiveness was proven in their use to power the longest unmanned airplane flight, lasting 14 days. The only drawback of these batteries is that they traditionally have a short lifespan as the cathode degrades very quickly.

Researchers at Pacific Northwest National Laboratory (PNNL) have discovered a new method of developing lithium-sulfur batteries, allowing them to drastically increase their longevity. Batteries are conventionally made of two parts, an anode and a cathode. A lithium-sulfur battery contains sulfur in the cathode, and although this better stores energy, the sulfur degrades easily. Most research has gone towards preventing the leakage of the sulfur cathode but the researchers at PNNL took a different approach; they used graphite, the same material found in pencils, to shield the anode from the cathode, making the battery’s components more stable. Their efforts lead to the battery being able to recharge over 400 times, much better than the previous 100 especially after such little testing.

Researchers at Tsinghua University in China improved on this result by using the recently discovered nanomaterial, graphene, in an intrinsically unstacked double-layer formation as a cathode material. By producing flakes of graphene, the researchers created a good support structure for the sulfur in the cathode, allowing it to produce in increased power output as well as being able to recharge 1000 times.

Using  renewable energy to power electric cars could cut the world’s greenhouse gas emissions by 25%. Although electric cars have been facing problems with battery efficiency, the work of the researchers at PNNL and Tsinghua University has paved the way for drastic improvements in lithium-sulfur batteries allowing for rapid adoption of electric cars in the future.



Sunday, March 9, 2014

Advancements in production of super-material graphene

The structure of a graphene sheet
As technology becomes more advanced and demanding, current materials are beginning to reach their limits. The size of silicon transistors in computer processors is beginning to plateau, and materials more suited for development on the nano-scale scale are greatly needed. Many of the earth’s rare elements are being used up, and even elements like copper are becoming expensive due to their use in technology.

The versatile material that could solve all these problems is graphene. When it was discovered in 2004 at the University of Manchester, it was called the first “two-dimensional” material produced because it is only one atom thick, and is made of carbon atoms in a honeycomb structure. This structure makes it not just extremely strong, but the strongest substance ever discovered, more than 300 times stronger than steel and Kevlar while remaining 1000 times lighter than paper.

These properties make graphene and ideal construction material for both the large and small scales, and also for creating safer and more efficient transportation vehicles due to graphene’s high strength and low weight. Graphene can also be used as a semiconductor. Silicon is reaching its limits; silicon transistors cannot be made much smaller, but graphene provides a more organized and versatile base material that could replace silicon transistors completely. Because graphene is an efficient conductor, even at the smallest scale, it could be useful creating tiny low-profile wires that could shrink electronics even further.

On top of this, because graphene is made from carbon, a very abundant element on earth, it is unlikely for there to be any shortages of graphene. This means that the cost can be very low once production techniques are refined, and also that the production will take less of a toll on the environment. Despite this, the development of production techniques is one of the greatest challenges for graphene today.

Researchers from Northwestern University found a new method of depositing graphene onto silver. Silver is an ideal material for graphene deposition because it is very stable and conductive. By coupling this with an electric charge, the researchers were able to force the carbon onto the silver in thin sheets with relatively high accuracy. With further development of this silver method, graphene production could increase, leading to a decrease in cost. Previously, a gas was heated so that it could form onto a plate, but this requires extreme precision and very high temperatures, resulting in a low yield.

Orange and yellow represent graphene growth on the dark red silver
This new production method does not just affect the graphene market however, it also has an impact on both the development and production of other “two-dimensional” materials. As scientists begin to use supercomputers to model new arrangements of atoms in a two-dimensional form, many more types of materials like graphene will need to be tested, such as two-dimensional boron structures that are being researched. This new method of production will help these discoveries advance more rapidly.

Graphene promises to make society more efficient, safer, and maybe even build a space elevator, but the current production method fails to produce enough graphene at a reasonable enough price to make any impact. The new silver deposition method is much more efficient and effective, unlocking the massive potential of graphene and other two-dimensional materials..


Monday, March 3, 2014

Portable X-ray can improve African health

X-ray imaging has been one of the most influential technologies on the detection and prevention of disease. Its ability to detect many of the world’s leading killers, such as cancer and heart disease, make it very valuable in preventative medicine. Despite its important role in medicine, little advancement has been made in X-ray equipment in the last 50 years, leaving it as a large, immobile, expensive machine stuck in a hospital. This makes it almost impossible for people in rural areas of developing countries to get access to X-ray equipment, rendering them unable to find out whether they have many of the common diseases. By the time they know what disease they do have, it may be too late for treatment, or the treatment may be too expensive.

To deal with the poor portability and availability of X-ray imaging equipment, Tribogenics, a Californian start-up, has developed a new handheld X-ray device. Instead of using a smaller and less-effective implementation of tradition X-ray technology, they created a new design from the ground up, starting with the concept of triboluminescence. Triboluminescence is an effect that when certain things separate, X-rays are emitted along with a flash of light. Using this concept, the engineers at Tribogenics were able to X-ray a finger using only a vacuum chamber, tape, and a piece of dental film, which inspired their new portable X-ray machine.

Another portable medical device is already being implemented in Africa with a similar purpose. Mobisante is developing portable ultrasound probes that are low-cost and easy to use. These devices are modeled after smartphones allowing them to be easily mass produced and easy to use. This targeted the problem of maternal death, which in countries such as Chad and Somalia as many as 1 in 14 women die giving birth.

A portable X-ray device could effectively go alongside ultrasound in third world countries, allowing hospitals to give X-rays as well as improve maternal health. One of the main advantages of the portability of these devices is that they can reach areas separated from hospitals. These portable devices could be moved between smaller local clinics in a rotation, allowing a greater population to be reached by their benefits.

Many of the people who suffer from lack of health care do so because of their remote location and lack of money. Donations of medical equipment to hospitals do not help these people, as they do not have the money to travel the long distance to the hospital or to pay for the care. This is the type of person that will benefit greatly from the introduction of portable, low-cost medical technology.


Friday, January 3, 2014

Settings career goals for engineering

All human actions are based on the desire to achieve a goal. A goal is, by definition, “the object of a person's ambition or effort.” Although all people make goals and achieve them, a person’s success in life is greatly determined by their ability to set long-term goals, and how seriously they take these objectives.

Anthony Fasano, in his book Engineer Your Own Success, lists 7 key elements in a successful engineering career. The first key element is “goals,” because they act as the “ultimate destination for our career.” In the words of Robert G. Allen, a self-made multi-millionaire, “The future you see is the future you get.”

Just imagining the future is not enough, one must go about the process of setting goals in a way that one can build on them and work relentlessly to achieve them. You can begin with a general idea of something they want to do and then make it more specific. “I want to be an engineer” becomes “I want to study engineering at a top college, then work my way up the ladder to become a leader at an engineering firm or start my own company.”

Next, you must question yourself by asking why you want to achieve this goal. For example: “I want to support myself and my family financially and do work that is rewarding.” Answering the question “why” leads to your real life goal. One can then reevaluate your career goal based on this.

The next question to ask yourself is: What do I need to do to achieve my career goal? Without specifics, a long-term goal becomes easy to put off or push away, and focus on other short-term goals. Specifying certain actions and deadlines makes it easier to get working and do the right work. Once you know the larger steps about how the goal can be achieved, breaking these larger steps down into smaller goals allows you to create an outline for your success.

An important aspect of goal-setting is thinking big. Anthony Fasano says in his book that the best way is to think big is to set “ideal” goals. Instead of stating what you think your job will be, state the ideal version of the job. Not only should you state what you ideally want to be doing, but also who you ideally want to be. Fasano also states that the reason many people do not achieve what they would say is their “ideal goal” is that they never actually aim for it. Reworking the smaller steps to aim at a big long-term goal may prove that the goal which originally seemed lofty and unattainable is actually reachable.

Using the S.M.A.R.T. system effectively breaks down the steps that make up your career goals. These steps must be specific, measurable, achievable, relevant, and time bound. A goal must be specific for it to be achieved in the most efficient manner. To be specific one must break down the goal into smaller pieces so that each step can be completed in the best order and in good time. If a goal is measurable then it is easy to keep track of progress, which is crucial to achieving the goal. These smaller goals that are part of a large goal must be achievable, so that the large goal can actually be accomplished, as all of the steps are necessary. Many people add extra steps that may not actually be necessary. Check that all steps relevant. Without a deadline, it will be more difficult to have urgency in accomplishing the goals you set.

Long-term goal setting is a skill seldom taught, but is crucial in the ability to live a fulfilling life. Setting up and planning to achieve long-term goals is setting yourself up for success.

I'd like to thank Anthony Fasano, author of Engineer Your Own Success for helping me with this blog. I'd recommend his book to anyone, even if they're not interested in engineering, as it has some very useful tips and strategies on how to approach studying and a career. His website,, is also very helpful.

Saturday, December 21, 2013

Nanotech turns plastic bags into future material

Earth’s largest structures are pushing the limits of what current materials can do on the macro scale, and earth’s smallest systems are in need of new materials more suited to the nano scale. Carbon nanotubes offer a solution on both fronts. They are semiconductors, making them a viable replacement for silicon. They are extremely strong, more than 100 times stronger than steel and six times lighter. This makes them ideal for building large things as well, such as vehicles or buildings.

One might wonder, then, why carbon nanotubes are almost never used in large structures. This is mainly due to the price. For 1 kg of carbon nanotubes about $200 or more would have to be paid. For that much, 1 metric ton of steel could be purchased. Researchers at the University of Adelaide are tackling two problems in one: The high cost of nanotubes and the excess of plastic bags.

Over 1 trillion plastic bags are used each year worldwide, none of which can be recycled using the normal recycling system and would become debris otherwise. Because these bags are made of carbon, they can be repurposed to manufacture carbon nanotubes. The researchers at University of Adelaide found that once vaporized, the bags were as effective in the production as the ethanol they were using previously.

Because no catalysts or solvents are used, the bags also have an advantage over ethanol in that they produce no toxic waste during production, they only produce excess plastic which could be reused. This would help reduce the price of the nanotubes, increasing the demand and also increasing the number of plastic bags being recycled through the production.

This method of production could also be used for other carbon-based materials of the future, such as carbon fiber, carbon nanofibers, and graphene. This low cost of carbon nanotubes would not only allow huge advances in engineering, but it would also improve world health. One example of carbon nanotubes’ health impact is their ability to be a catalyst for bone regrowth when injected into damaged bone. This could become a low-cost procedure using cheap nanotubes.

With cost being the only thing holding back carbon nanotube usage in the field, these cost reducing production solutions are a welcome advancement. The recycling of an environmentally damaging waste to produce these nanotubes is another plus,  making them certain to impact the future of engineering and medicine.


Wednesday, December 18, 2013

Nanotechnology Fights Osteoporosis

The average person living in a developed country can expect to fracture a bone in their body two times in their lifetime, and people in developing countries may be even more prone to bone fracture. Over 40 million people in the U.S. have osteoporosis, a condition that makes bones extremely brittle and prone to breaking, or are at high risk of having it. Most people only learn they have osteoporosis when they are first injured, making treatment more difficult.

Treatment for bone fractures is also expensive and inaccurate, requiring medicine to enter the bloodstream, circulating throughout the whole body. This means that if the medicine reaches the fracture needing treatment, it can arrive in very small quantities, causing little healing. It also means that too much medicine could arrive at the wrong place in the body, potentially causing problems.

Osteoporosis is killing people’s active lifestyles, and causing pain to the people who suffer with it. Being such a common condition, one would think that it would be routinely tested for, but it is not. By using new methods of early detection, and faster, more effective methods of treatment using nanotechnology, osteoporosis could become a minor condition instead of a life-changing one.

Most people first learn they have osteoporosis when they first sustain a bone fracture, which is a serious medical condition. This makes early detection particularly important for the treatment of osteoporosis, so a low cost system for osteoporosis detection is being developed at the University of Southampton in England. Patient are normally tested by X-ray, which is time consuming and requires expensive equipment located in a hospital. The new method, however, uses only a microscopic needle attached to a small measuring device.

This needle penetrates the bone and measures the force needed to do so, which determines bone health quickly and almost cost-free. This could be used anywhere, and could be easily implemented by small clinics, allowing people to get tested quickly and cheaply; ideal for the elderly who are at high risk, and may not want to travel all the way to the hospital.

A team of researchers at Pennsylvania State University and Boston University have developed a new method of delivering bone-healing drugs using nanoparticles. The researchers based their new method off of a well known fact: When bones break, minerals inside the bone release ions that create an electronic field. The researchers found that when quantum dots, a type of synthetic nanoparticle, were added near the fracture, they were attracted to the fracture and went directly to it, as if it was a homing beacon. This makes the drug super efficient and effective.

Some osteoporosis drugs on the market now, such as zoledronic acid, not only slow down bone decay, but slow bone regrowth also. This prevents bones from healing completely, which is another reason that new drugs using nanotechnology would be a welcome change from the standard ones used today.

Using low-cost early detection systems and efficient treatment methods, osteoporosis would have an impact on fewer peoples lives. One third of people above 70 who sustain a hip fracture, often due to the disease, die within a year due to the injury; killing 1,100 people every month. This number could be greatly curbed, both by detecting osteoporosis earlier and preventing the fracture, or by using new nanotechnology to heal the bones afterwards, preventing death. This could reduce the number of osteoporosis related deaths to almost zero, and ease the lives of people dealing with the condition.


Saturday, August 31, 2013

Foldable and printable electronics possible with graphene

Advances in electronics have expanded the range of applications. One new application of electronics that is becoming more prevalent is insertion into the human body. Current silicon-based electronics are not flexible enough to allow proper integration into the human body in most cases.

Graphene, a fairly new nanomaterial, could solve this problem. It is the best candidate for creating foldable circuits because it is highly conductive, chemically stable, and mechanically flexible. This means that it can exist in thin layers that would bend easily while still being an effective conductor. This is possible because graphene is incredibly strong, about 200 times stronger than steel. The scientists that were able to produce a 1-atom thick sheet of graphene, Andre Geim and Kostya Novoselov from the University of Manchester, were awarded the Nobel Prize for physics in 2010.

Researchers at Northwestern University in Illinois are creating electronics with paper-like properties by using graphene. These could open new doors in the implementation of electronics into the human body and in medical devices. The development of foldable electronics could also spark new development of electronics based on the foldable ones.

The first problem that arises when using graphene is that it is difficult to obtain. The traditional way of obtaining graphite was to break it off of graphite molecules using an oxidization process. This was effective at creating the graphene, but it lost much of its conductivity in the process, making it unusable in electronics.

The researchers at Northwestern University have used a different method to obtain the graphene. They perform exfoliation on the graphite using ethanol and ethyl cellulose. This process is more effective than the oxidization because it creates little waste, and most importantly, creates graphene with its original high conductivity. This new process is not only important in creating circuits, but could find application in any technology where graphene is needed.

Now that the graphene has been obtained, the next step is to apply it to the paper, or whatever material the circuit is being produced on. The researchers at Northwestern University found a way to incorporate the ~1 nm (one 10,000th the size of a red blood cell) sized flakes of graphene into inkjet printer ink. This is done by adding the graphene flakes in large quantities to a solvent, creating the ink that can be used in printers.

This ink has many potential applications. A low-cost, printable ink could create educational opportunities for students without access to more advanced materials, especially students in developing countries. Many schools already have inkjet printers, so with the development of software for modeling the printable circuits, students would be able to print their own extremely complex circuits on paper, and then design and their own electronic projects with them. This could get more students interested in science, technology, engineering, and math (STEM) at a younger age by allowing them to do hands-on electronics projects at a low cost.

Graphene is one of the most versatile materials, and this is just one of the many potential applications we could see in the future. Graphene also can be integrated into computer processors, and any materials that need to be extremely strong. Once manufacturing methods become more polished, and the price becomes cheaper, graphene could become one of the most influential materials ever discovered.