What Advancements in Material Sciences Have Been Made That No One Is Talking About?
Science is moving at an aggressive pace. Oftentimes, it’s too fast for anyone to keep up with, and so some new findings and applications fall between the cracks. Here is but a few of them. It is my intent to update this list as more are uncovered, so check in every once and a while for what I hope you too will find to be an advancement in materials that no one is talking about.
Water is simply amazing. It destroys, it creates, and it is what you and I are mostly made of. To further demonstrate the amazing abilities of water, scientists at Columbia University led by Ozgur Sahin have developed an evaporation powered 100 grams car. Yes, it’s small and not very fast but it is a prototype and the process for its locomotion is amazing. It makes use of 100 “spore coated tapes,” each 4 inches long, which expand and contract as levels of H20 in the air change. A chamber full of the special paper hangs from rings of concentric circles and is wettened, increasing the length of the tape. Half of the ring at any time is enclosed while the other half is exposed to air, allowing evaporation. Now, here is the magic. The wet paper has a center of mass and so does the dry paper, but as evaporation occurs, the center of torque begins to shift so that the two are not in alignment. Add to this the paper curling inward as it dries and you have a further net torque change. As this spin occurs, a rubber band attached to the pivot axis spins and…voila, a vehicle is the result! While no one will be rushing to the store to get one, it could have applications in micromachinery (Tenning, Ornes).
One of the technological battles comparable to increasing processor speeds in a computer is the need for a thinner and thinner lens. Many technology fields would benefit from an even lower curvature lens, of which Frederico Capasso and his team at Harvard University accomplished in 2012. They were able to make “microscopic silicon ridges” which caused light to bend in a certain way, depending on the angle of incident. In fact, based on the placement of the ridges you could conceivably get many focal length possibilities. However, the ridges only allow for one wavelength to have high precision, not suitable for any everyday means. But advancements are being made, for in February 2015 the same team was able to get at least some RGB wavelengths to happen at once (Patel "The").
Solar Cell Efficiency
How can we increase the efficiency of solar panels? After all, what holds back most photovoltaic cells from converting all the solar photons striking it into electricity is the wavelength restrictions. Light has many different wavelength components and when you couple this with the necessary restrictions to excite the solar cells and so only 20% of it becomes electricity with this system. An alternative would be solar thermal cells, which take the photons and convert them into heat, which is then converted into electricity. But even this system peaks at 30% efficiency and it requires a lot of space for it to work and needs the light to be focused to generate heat. But what if the two were combined into one? (Giller).
That is what MIT researchers looked into. They were able to develop a solar-thermophotovoltaic device which combines the best of both technologies by converting the photons into heat first and having carbon nanotubes absorbing that. They are great for this purpose and also have the added benefit of being able to absorb nearly the entire solar spectrum. As the heat is transferred through the tubes, it ends up in a photonic crystal layered with silicon and silicon dioxide which at about 1000 degrees Celsius starts to glow. This results in an emission of photons which are more suitable for stimulating electrons. However, this device is only at 3% efficiency but with growth it can likely be improved upon (Ibid).
Many advancements are made in high-caliber laboratories with a large amount of funding to back it up. So, imagine when Brad Musselman, a senior at Knox College in Galesburg, submitted an honors project entitled, “Axial Site Reactivity of Multilinear Copper (II) Carboxylate Metalomesogens.” Sounds fun enough, no? It is, for a major advancement in a field that had been around since the 60s was achieved. Metalomesogens are liquid crystals that also have some solid properties but sadly fall apart easily when making compounds out of them. Brad played with the levels of sipper, caprolactam (a nylon ancestor), and a solvent in the hopes of providing the right conditions. These things added to the mix as it was heated produced a color change from blue to brown in the solution that hinted to Brad that the right conditions for the metalomesogen transformation was taking place and so to continue that, some toluene would be added. Once cooled, crystals would form and x-ray diffraction and infrared spectroscopy would later confirm the material was as desired. Such materials can possibly have applications in synthezation of different compounds and reduce waste materials that are often encountered in many industries (Chozen).
Imagine lining standard stock paper with a nano particle layering consisting of Prussian blue and titanium dioxide. When this is hit with UV light, electrons exchange between those layers and causes the blue to become white. With a filter on top of this, one could print blue text onto the white paper and within a span of 5 days it will disappear as the paper becomes blue again. Then hit it with UV and voila, white paper again. The best part is that the process can be replicated on the same piece of paper up to 80 times (Peplow).
Handle the Heat
Technology that can deal with extreme temperatures would be important for several industries such as rockets and reactors. One of the latest developments in this field is silicon carbide fibers with ceramic shells between them. Carbon nanotubes with a silicon carbide surface are dipped into "ultra fine silicon powder" and then cooked together, changing the carbon nanotubes to silicon carbide fibers. The materials created with this can withstand 2000 degrees Celsius, but when subjected to high pressure the material cracks and obviously that would be bad. So researchers at Rice University and the Glenn Research Center created a "fuzzy" version, where the fibers were much more rough on their surfaces. This enabled them to grab better and therefore maintain structural integrity, with an increase in strength nearly 4 times that of its unaltered predecessor (Patel "Hot").
Alternative to Lithium Ion Batteries
Remember when those phones were catching on fire? That was because of a lithium-ion issue. But what exactly is a lithium-ion battery? It is a liquid electrolyte involving an organic solvent and dissolved salts. Ions in this mix flow with ease over a membrane which then induces a current. The major catch to this system is dendrite formation, aka microscopic lithium fibers. They can build up and cause short circuits which lead to heat ups and...fire! Surely there must be an alternative to this...somewhere (Sedacces 23).
Cyrus Rustomji (University of California at San Diego) may have a solution: gas-based batteries. The solvent would be a liquefied floronethane gas instead of the organic one. The battery was charged and drained 400 times and then compared to its lithium counterpart. The charge it held was nearly the same as the initial charge but the lithium was only 20% its original capacity. Another advantage the gas had was lack of flammability. If punctured, a lithium battery will interact with the oxygen in the air and cause a reaction, but in the case of the gas it just releases into the air as it loses pressure and will not explode. And as an added bonus, the gas battery operates at -60 degrees Celsius. How heating the battery impacts its performance remains to be seen (Ibid).
Chozen, Pam. “Unpacking an Honors Project.” Knox College Spring 2016: 19-24.
Giller, Geoffrey. “Solar Tries Two.” Scientific American Apr. 2015: 27. Print.
Ornes, Stephen. “Spore Power.” Discover Apr. 2016: 14. Print.
Patel, Prachi. "Hot Rockets." Sceintific American Jun. 2017. Print. 20.
---. “The Lens Descends.” Scientific American May 2015: 22. Print.
Peplow, Mark. "Print, Wipe, Rewrite." Scientific American Jun. 2017. Print. 16.
Sedacces, Matthew. "Better Batteries." Scientific American Oct. 2017. Print. 23.
Tenning, Maria. “Water, Water, Everywhere.” Scientific American Sept. 2015: 26. Print.
© 2018 Leonard Kelley