Just mix and serve

Transparent electrodes, anti-radiation space suits, and batteries that change colors - these are just a few of the applications that can be developed in the future with the help of nanomaterials recently produced in the laboratory of Prof. Boris RybchinskyFrom the Department of Organic Chemistry at the Weizmann Institute of Science. These composite materials, which combine carbon nanotubes and highly available organic dyes, are very simple to manufacture, and have a unique combination of properties.

Carbon nanotubes are extremely strong, cylinder-like nanostructures made of carbon atoms. In the past, scientists tried to mix dyes with these nanotubes, but usually used dye compounds that contained additional ingredients, and therefore attributed the resulting properties to these ingredients. The institute's scientists, on the other hand, mixed nanotubes with a fairly simple organic dye into the solution - and were amazed by the result. asreport in the scientific journal Advanced materials, mixing these two components alone was sufficient to create a stable and electrically conductive composite material, in which the nanotubes are almost completely separated from each other. The separation of the tubes is of enormous importance, since nanotubes tend to stick to each other - a feature that greatly limits their use in nanotechnology engineering. "We hypothesized that the combination would work, but we did not expect such a dramatic result. It was simply wonderful," recalls Prof. Rivchinsky.

We assumed the combination would work, but we didn't expect such a dramatic result. It was just wonderful"

It is known that when carbon nanotubes are mixed with the dye used by the scientists, the dye molecules "absorb" electrons from the nanotubes, thus creating molecular clusters with an electrical charge. Prof. Rivchinsky and his group members discovered that this fact also makes the aggregates hydrophilic ("water lovers"), thus maintaining the separation between the nanotubes in the solution. Besides being a simple and cheap method for separating nanotubes, the combination also improved the electrical properties of the tubes without damaging their mechanical properties.

The composite material itself, which was prepared in an aqueous solution, and contains carbon nanotubes in the form of threads and nanocrystals of the coloring material, may lead to many applications thanks to the combination of the properties of its components: it is flexible, stable at high temperatures, and conducts electric current efficiently. A thin layer of the material over different materials could make it possible to produce, among other things, space suits that protect against radioactive radiation. Other applications, such as highly efficient electrodes, may benefit from the material's many pores, which increase its surface area. Thus, for example, a thin and transparent coating layer of the material will allow the production of transparent electrodes for building displays in various electronic devices. The use of paint opens the door to other applications, such as conductive or antistatic paints for cars and airplanes, or batteries that change color when they are discharged.