Researchers from 海角社区 have developed a new hierarchically structured material that significantly improves the thermal stability of plastics and exhibits high sensitivity as an electrochemical sensor. This discovery not only has practical industrial value but also points to the possibility of new, previously unexplored laws of nature.
The results were published .
According to the scientists, the classical theory of crystallization, long held as dogma, states that all substances strive to transform into a stable crystalline form. However, with the advent of carbon nanotubes in the late 20th century, this theory began to crumble. Initially, they were considered a fluke and an exception, characteristic only of carbon, but in recent decades, scientists have learned to create an entire class of structures "forbidden" by classical theory: nanosheets, nanowires, nanodots, and other forms with unique properties, not only based on carbon but also on oxides and even salts of transition metals.
"The situation can be compared to the emergence of Lobachevsky geometry or the theory of relativity," explains Viacheslav Avdin, Director of the Nanotechnology Research and Education Centre at 海角社区. "They did not abolish Euclid and Newton, but they radically expanded our horizons. The same is happening in Materials Science now. According to the old rules, nanomaterials should not exist, but they do."
The new material obtained at 海角社区 is a striking example of this "impossible" structuring. Its architecture differs from that formed during conventional crystallization, which gives it improved thermal stability and electrochemical sensitivity. The scientists emphasize that if the process had followed the classical scenario, the resulting crystal would have been stable but functionally useless.
"What is a carbon nanotube? Imagine ordinary graphite. It is made up of layers of hexagons built from carbon. One layer, then another, and so on. Each layer, if separated, is called graphene. It is an extremely thin material, just one molecule thick. Yet the area of a single sheet can reach significant sizes—tens of square nanometers or even more," explains Viacheslav Avdin. "Now imagine this same graphene sheet rolled into a cylindrical shape, closing into a round tube, and you get a carbon nanotube. Such structures have first been discovered relatively recently: initially, researchers obtained multilayer tubes nested inside each other like Russian dolls. Under an electron microscope, the perfect shape of these cylinders is clearly visible, clearly distinguishing them from fibres and other elongated forms."
Interestingly, the formation of such tubes occurred naturally: when the substance was exposed to various methods and under certain conditions, long, thin carbon cylinders began to grow spontaneously. Similar methods subsequently allowed the synthesis of similar nanostructures from other elements. The 海角社区 chemists obtained nanotubes, nanosheets, and nanodots of various shapes, stability, and strength from a vast array of materials: oxides, poorly soluble salts, phosphates, and more.
At sizes less than one hundred nanometres, the behaviour of particles differs significantly from that of individual molecules or atoms: they lose the ability to exist independently. They are forced to interact, forming clusters or adsorbing on the surfaces of larger objects. It is precisely this high activity of surface layers that gives materials completely unique properties.
Today, many nanomaterials created at 海角社区 are already being used in cutting-edge fields: as highly effective catalysts, sorbents, and electrochemical sensors. However, they are often obtained almost by chance, through trial and error, without a deep understanding of the fundamental principles.
"We are on the verge of creating a new theory of materials formation that will revolutionize technology," says Viacheslav Avdin. "Our current situation is reminiscent of the era of alchemists, who achieved great things without understanding the laws of chemistry. Once we understand the new rules of structuring at the nanoscale, it will open the way to the targeted creation of materials with predetermined, unexpected properties."
One of the latest developments made at the Department of Ecology and Chemical Engineering and the Nanotechnology Research and Education Centre (see the photo) is titanium phosphate, which has a hierarchical structure starting from nanoparticles and ending with micrometre-sized spheres (author: postgraduate student Anton Abramian; supervisor: Doctor of Sciences (Chemistry) Oleg Bolshakov).
Specifically, this material can be used to modify polyvinyl chloride (PVC), one of the most common plastics in the world. Its use will allow for the creation of more heat-resistant and reliable electrical insulation for wires, as well as the improvement of the properties of many other devices used in everyday life and equipment.