Home > Nanotechnology Columns > The Future of Nanotechnology > How Nanocrystal Technology Is Changing the World
 |
Amanda Richter |
Abstract:
If someone asked you to name an efficient material for building batteries, you probably wouldn't think of trees — but that may be changing, thanks to work researchers at McMaster University are doing with nanocrystal technology.
October 6th, 2015
How Nanocrystal Technology Is Changing the World
If someone asked you to name an efficient material for building batteries, you probably wouldn't think of trees — but that may be changing, thanks to work researchers at McMaster University are doing with nanocrystal technology. According to Phys.org, researchers Emily Cranston and Igor Zhitomirsky have figured out a way to use nano-sized crystals made of cellulose, the same organic material found in plant cell walls and wood, to create a microscopic foam. The foam, which looks like tiny grains of uncooked rice, can trap energy-storing nanoparticles in a way similar to that of a rechargeable battery, only with greater sustainability, higher power density and faster charging capability. Cellulose combines strength with flexibility, making the researchers' nanocrystal battery foam an excellent method of storing energy with a variety of applications, including in hybrid and electric vehicles. This breakthrough is just one of the many exciting ways that nanocrystal technology is changing the world.
A New Fuel Source
Nanocrystals have always been part of the natural world, but scientists are just beginning to understand how they work. A nanocrystal is so named because its crystalline structure is only 1 to 100 nanometers in size (a nanometer is about one million times smaller than an ant). A sheet of paper is about 100,000 nanometers thick.
These tiny dimensions give nanocrystals some unusual properties. For instance, a nanocrystal structure can be spread out over a surface to provide it with an extremely thin layer of material possessing its own chemical properties. Such a layer can expose a wide number of atoms on its surface to serve as a catalyst for chemical reactions. This means chemical reactions between exposed atoms and the surrounding environment can occur faster on a nanocrystal surface than on regular surfaces, enabling reactions to occur at lower temperatures as well.
This has many potential practical applications. One is the possibility of using nanocrystals as an efficient, sustainable fuel source. As How Stuff Works explains, nanocrystals could potentially serve as a catalyst to convert corn into ethanol fuel more efficiently.
Nanocrystals can also make hydrogen fuel cells produce electricity more efficiently and cheaply using less storage space. A hydrogen cell reacts with elements such as hydrogen and oxygen to generate electricity, so a nanocrystal structure would enable such reactions to occur more quickly. Moreover, hydrogen cells use platinum as a catalyst, which is expensive, but platinum nanocrystals would require less material (and hence, are less expensive) to produce the same result.
Finally, most fuel cells use liquids to collect electrodes because of liquids' superior conductive properties, but nanocrystals are so small they can be infused into solid substances, making the solids themselves more conducive and reducing the size needed to store fuel cells.
Nanocrystals in Biology and Medicine
Nanocrystals also possess optical properties that have applications in biology and medicine. For instance, biologists once thought that chameleons changed colors by using pigments contained in organelles in their skin cells. But in 2014, University of Geneva researchers discovered that chameleons' skin contains a layer of light-reflecting cells embedded with a lattice of guanine nanocrystals. Depending on how close the crystals are to each other, they reflect different wavelengths of light. When chameleons are relaxed, the crystals remain closely packed and reflect short wavelengths such as blue, which combine with yellow pigments in the chameleons' skin to create a green camouflage. But excitement causes the nanocrystals to spread out, reflecting longer wavelengths such as yellow, orange and red.
Medicine may soon benefit from artificial reverse engineering of such natural nanocrystal optical effects. Science Times reports that a team of Chinese researchers at Xi'an Jiaotong University has designed a way to precisely control nanocrystal size and shape to determine which color of light gets produced when materials are stimulated with electricity or ultraviolet light. By then using the nanocrystals as a staining agent for microscope slides, the researchers were able to get cancer cells to display in a different color than normal cells. This technique could enable oncologists to more easily spot cancerous cells, even in small concentration.
Making High Resolution TVs Less Expensive
Nanocrystals' optical properties are also changing the way we watch TV, in the form of SUHD "quantum dot" sets. As Dish's The Dig explains, today's 4K TVs have a horizontal resolution of approximately 4,000 pixels, which is about four times that of a 1080p HD TV, translating into twice the resolution. Many of today's 4K TVs use OLED technology, which relies on thin, light-emitting films to generate light and color, producing strong black levels, brightness and contrast. However, the downside of OLED TVs is that they're expensive, often running $2,500 and up. By spreading a thin layer of nanocrystals across a TV's LCD control panel, SUHD can achieve the same visual effects as an OLED TV but for a reduced cost.
Nanocrystal Computers
The same quantum dot technology used for SUHD TVs may also help make computers faster. Computer engineers are currently working toward a faster generation of "quantum computers" that speed up processing speed by replacing the traditional bit-based memory storage system with a quantum bit system, in which atomic phenomena get encoded as "qubits" that can each contain up to two bits of information. Unfortunately, achieving a practical quantum computer has been difficult due to the difficulty getting atoms to behave. According to Nanotechweb.org, McGill University researchers are also experimenting with using silicon nanocrystals and light to speed up how fast information can travel around a computer chip.
Bookmark:
 |
||
 |
||
| The latest news from around the world, FREE | ||
 |
||
|
|
||
| Premium Products | ||
 |
||
|
Only the news you want to read!
Learn More |
||
 |
||
|
Full-service, expert consulting
Learn More |
||
|
|
||