Author Archives: cj

Super Batteries

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Some people feel like they are always stuck to the outlet because our current batteries cannot hold enough power and degrade quickly. (c) JuralMin, released under Creative Commons CC0

Have you ever been in a situation where you need to charge your phone multiples times a day in order to maintain its battery level? We’ve all probably experienced times when we desperately need to use our phones but the battery is completely drained, with only moderate use throughout the day. Why is it that current cellular device technology has improved significantly, but battery quality has not?

Recently, researchers at the University of Cambridge have developed a new type of battery that may soon solve this problem and increase the productivity and lifespan of the modern lithium-ion battery. This new type of battery, called the lithium-sulfur battery, takes inspiration from the villi in our digestive intestinal tract. It is predicted that these next-generation batteries could potentially hold up to five times the energy that a tradition lithium-ion battery can, without increasing the size of the battery.

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A illustration of what villi look like in the small intestine (c) nobeatsofierce

Villi are finger-like protrusions lining the intestinal tract which increase the surface area needed for the absorption of nutrients. In the battery, zinc oxide wires stick out like villi from the surface of one of the battery’s electrodes, the part of the battery that generates electrons.

In traditional lithium-ion batteries, active material in the battery that break off the flat electrode are lost and lead to the degradation of the battery. This new villus configuration allows precious “battery nutrients” that break off the electrode to be attracted to the villi wires, just like how the villi in the intestines attract and absorb the nutrients on our food. The material attracted by the zinc oxide wires can then be reused for the production of electrochemical energy, greatly increasing the lifespan of the battery.

The lithium-sulfur battery also has a higher energy density than regular lithium-ion batteries due to the ability of sulfur to hold a higher number of lithium-ions than carbon can in the current battery model. To illustrate this, imagine that the battery is a factory and lithium ions are the workers. The carbon factory only has enough capacity for 100 workers. However, the sulfur factory can have >500 workers. Which factory will be more productive? This is why carbon is replaced by sulfur in the new-type battery, due to sulfur’s ability to hold more lithium-ion “workers” to generate more energy.

These breakthrough changes, substituting carbon for sulfur and the addition of zinc oxide “villi”, result in a new type of battery that surpasses the lithium-ion battery in terms of energy capacity as well as battery lifespan.

“By taking our inspiration from the natural world, we were able to come up with a solution that we hope will accelerate the development of next-generation batteries.” said the study’s lead author Teng Zhao.

However, the battery is currently not yet ready for commercial use and will probably not be available without further research and development.

The new advances in battery technology is exciting and brings hope to all of us who use battery-powered devices. I think it’s about time that the batteries we commonly use now receive an upgrade. Even though this new technology has not yet been perfected, I believe that through the discovery of lithium-sulfur batteries we can move towards developing better batteries for the future.

-Charlie Wei


References:

University of Cambridge. “Next-generation smartphone battery inspired by the gut.” ScienceDaily. ScienceDaily, 26 October 2016. <www.sciencedaily.com/releases/2016/10/161026102701.htm>.

The World’s Smallest Machines!

The 2016 Nobel prize in chemistry was awarded to Jean-Pierre Sauvage of the University of Strasbourg for the design and synthesis of molecular machines. As a chemistry undergraduate myself, the idea of molecular machines immediately peaked my interests. These machines are no different than the gears that rotate the wheels of our cars and spin the fans that cool the computer chips inside our computers. Now you might be asking, what’s so spectacular about that? The fact is, these machines are so small they are invisible to our naked eye; they are so tiny that even under a magnifying glass you wouldn’t even see a spec.

Jean-Pierre Sauvage and his research team first proposed the idea of molecular machines in 1983 when they successfully linked two ring-shaped molecules into one structure called a “catenane”. The linked rings acted like two gears that can move mechanically with respect to each other just like any other gear in the macroscopic world. This simple discovery has propelled the research till present day. It has now been more than 30 years since the initial proposal of molecular machines with only a two gear system.

This is the crystal structure of catenane discovered by Sauvage and his team in 1985. Released under the GNU Free Documentation License

This is the crystal structure of catenane discovered by Sauvage and his team in 1985. (c) M stone, released under the GNU Free Documentation License

Jean-Pierre Sauvage and his research team has perfected the simple two-ringed molecule into a sophisticated system of many molecules that can be designed to perform certain tasks when energy is added. As of right now, Sauvage’s team has been able to display spinning of cranks and wheels at the microscopic level. In terms of development, their systems are equivalent to the electric motors during the 1830s. Without a doubt, what Sauvage and his team have discovered is just the tip of the iceberg. These molecular machines could potentially be further developed and used for things such as new materials, sensors and energy storage systems, and I’m excited to see the applications of these molecular motors in our everyday lives. Maybe one day when molecular motors become an integral part of our world, just like the electrical motors we use now, we will look back and truly appreciate Sauvage and the other scientists for the work they have put into developing these amazingly small but complex nano-machines.

 

-Charlie Wei


References:

Press Release: The Nobel Prize in Chemistry 2016 http://www.nobelprize.org/nobel_prizes/chemistry/laureates/2016/press.html (accessed Oct 12, 2016).

Jean-Pierre Sauvage – Facts https://www.nobelprize.org/nobel_prizes/chemistry/laureates/2016/sauvage-facts.html (accessed Oct 12, 2016).

Transformations of Fullerene http://www.org-chem.org/yuuki/catenane/catenane_en.html (accessed Oct 12, 2016).

A Solution for Climate Change?

CO2 concentrations over the last 400,000 years

A graph showing the rise and fall of CO2 concentration in the atmosphere, recorded over thousands of years. The magnified area indicates the dramatic increase of CO2 concentration during the Industrial Revolution. (c) Robert A. Rohde, used under Creative Commons Attribution-Share Alike 3.0 Unported

There is no doubt that climate change is real, dangerous, and occurring at an alarming rate that is unprecedented in the past 1,300 years. A major of the cause of this change is due to carbon dioxide gas, the product of burning fossil fuels for energy to run our cars, factories, for the production of electricity, and more. Carbon dioxide, one of many greenhouse gas, naturally acts as sort of a “blanket”, absorbing and emitting infrared radiation from the earth, causing the atmosphere to warm up, which known as the greenhouse effect.

A diagram illustrating the greenhouse effect.

A diagram illustrating the greenhouse effect. (c) US EPA used under public domain

Initiatives to reduce carbon dioxide emissions have already been implemented in our everyday lives, for example a simple thing like biking or taking public transit can reduce the amount of carbon dioxide emitted by automobiles. However, new carbon dioxide emissions data shows that our  efforts are not paying off. Every year, it is estimated that 38 billion tons of unnecessary carbon dioxide is released into the atmosphere. Even as you read this article 2.4 million pounds of this greenhouse gas is released into the atmosphere per second!

It seems that our efforts to reduce carbon dioxide emissions have failed and each year we can see a steady increase in emissions. Our economic and societal infrastructure has made us incredibly dependent on burni

Simple illustration of the conversion of CO2 into CO using silicon. (c) Chenxi Qian, used under Creative Commons Attribution 4.0 International License.

ng fossil fuels for energy. Perhaps the real solution lies in taking the excess carbon dioxide gas and converting it back into usable energy.

Recently, scientists from the University of Toronto believe to have discovered a method of converting carbon dioxide gas into energy-rich fuel. Professor Geoffrey Ozin and his team have developed a method using silicon, naturally found in sand, to efficiently and selectively convert gaseous carbon dioxide to carbon monoxide without any harmful emissions. Carbon monoxide can then be converted into hydrocarbon fuels such as petrol through a series of chemical reactions known as the Fischer-Tropsch process.

“A chemistry solution to climate change requires a material that is a highly active and selective catalyst to enable the conversion of CO₂ to fuel. It also needs to be made of elements that are low cost, non-toxic and readily available,” said Dr. Ozin.

Right now they are working on ways to increase the activity, enhance the scale, and boost the rate of production. Hopefully in the near future, there will be even more research dedicated to converting other greenhouse gases, not just carbon dioxide, into reusable energy, and then maybe we will be able to resolve the issues that have been caused by the detrimental amounts of greenhouse gases in our atmosphere.

– Charlie Wei