In Russia, they created an electrochemical nanoactuator that can move microscopic objects. This was reported by the press service of the RNF.
Chemists distinguish a special type of reaction – catalysis at the interface of water and air. Such reactions occur faster – scientists have not yet understood why, but have already found many useful applications. In particular, reactions on air bubbles in water are used to detoxify and disinfect liquids.
Specialists of the Yaroslavl branch of KA. Valieva RAS and colleagues from other universities have found a way to use one of these reactions – the spontaneous combustion of a mixture of hydrogen and oxygen in nanobubbles – to power a nanodrive. For example, it can be used to move microscopic containers of drugs in the bloodstream to deliver them in a targeted manner, or to manipulate a substance in microscopic “labs on a chip.”
The nanodrive is a small working chamber, slightly larger than a hair’s thickness: the electrodes are placed on a silicon wafer, the side walls of the chamber are made of a photosensitive polymer, and the upper wall is made in the form of an elastic membrane. . The chamber is filled with an electrolyte, which is a solution containing many ions and therefore able to conduct current. A high-frequency alternating voltage is applied to the electrodes, as a result of which water is split into oxygen and hydrogen, and nanobubbles containing these gases are formed – in fact, hydrogen fuel is obtained. The bubbles raise the membrane, which has the ability, for example, to push fluid through microchannels or do other mechanical work. The membrane then returns to its original position due to a spontaneous reaction between the hydrogen and oxygen nanobubbles. It takes only 100 milliseconds to completely remove the membrane and return to its original state – almost the same time as a hummingbird flaps its wings – which means that extremely fast micro-machines can also be controlled.
The authors were also able to prevent rapid wear of the machine by coating the aluminum electrodes with a layer of ruthenium, which is a good current conductor. As a result, they were able to keep the device running continuously for five hours without reducing the available power.
Previously at MSU to solveWhat is ionic pollution in Moscow precipitation.