Scientists at Rice University have found something new about a special class of 2D materials that could be useful for creating new devices. Boris Yakobson, a scientist from the same university, and his team learned about an extra capability of ferroelectric 2D materials that may be used in devices made in the future.
A recent study found out that ferroelectric materials, which can bend when given an electric shock, can be used as tiny switches or engines.
2D materials are made up of only one layer of atoms and they’re very thin – about a few nanometers! People are really interested in these materials because they can be used for things like cell phones and medical equipment since they have great physical, electrical, chemical, and optical properties.
2D materials are very thin and can easily bend. In single-layer ferroelectrics, this creates a surprise weird bending movement of its own. We found out that the way the material bends is connected to how it acts as a ferroelectric. So, what we did was find out about a fun property in 2D materials and then apply it for something useful.
Boris Yakobson
Ferroelectrics are materials made up of positive and negative charged particles that can be rearranged to create something called spontaneous polarization. This means the particles sort themselves into different groups based on their electrical charge.
Rice postdoctoral research associate Jun-Jie Zhang, who was in charge of the study, says an interesting thing about these particles is that they cannot be identical. Some of them are bigger while others are smaller, causing a break in the layer symmetry.
The atoms or ions in a 2D material layer can be acted upon by something called polarization. This causes the bigger atoms to get pushed to one side and the small ones go to the other side. This uneven spread of them causes the surface of the material to bend, which creates a type of electric charge known as ferroelectricity.
“In ferroelectric materials, instead of staying flat, they will bend. You can control which direction it bends by applying voltage to it. This means that you can use it as an actuator. An actuator is a device that changes signals like electric ones into movement or action.”
A study examined a special type of material called 2D indium phosphide to determine whether it had properties similar to other materials in the same group, which are referred to as ferroelectrics.
Researchers have discovered a new feature called “flexing behavior”, which must be tested in a lab for certain substances. It can act like an electronic switch and is very fast and sensitive. This means that controlling things such as turbines, electrical engines or telescopes becomes much easier with just a tiny local signal. In other words, these actuators are useful for doing all those kinds of tasks quickly and accurately!
When you get in your car, there are buttons and switches that make it easier than ever. You don’t have to manually roll down the window with a crank anymore – all you need to do is flip a switch!
The U.S Army Research Office and the Office of Naval research funded a study. The National Science Foundation also provided computing resources for it. The two studies that were part of this research included finding risk factors of getting severe COVID-19 in China, and analyzing genetic susceptibility to a sort of eye damage caused by diabetes in people from Southern China.
Researchers are studying how optical coherence tomography can be used to measure retinal ganglion cells in glaucoma. Scientists have also been looking at the distribution of substances called lanosterol synthase and lanosterol in the eyes of rats, as well as exploring how a protein called brain-derived neurotrophic factor precursor can affect behavior and cell death pathways in rats’ brains after stroke-related depression. Lastly, another research team is working on seeing if something called paeoniflorin can protect rat retinas from decreased blood flow (ischemia).
