Nanostructuring often makes materials very powerful in many applications. Some nanomaterials take on the desired complex structures independently during their creation process. Scientists from the University of Hamburg, DESY, ESRF and the Ludwig Maximilians University in Munich have studied the formation of cobalt oxide crystals just a few nanometers in size and how they assemble, while they are still being formed. The results are published in Nature Communications.
Nanomaterials have special properties that make them more effective than conventional materials in various applications. In sensors and catalysts (in green energy production, such as water splitting into energy-rich hydrogen and oxygen) the important chemical processes happen at the surface. Nanostructured materials, even in small amounts, provide a very large surface and are therefore suitable for this kind of applications.
Further potential arises due to the variety of shapes and material combinations that are conceivable on the nanoscale. However, establishing the exact shape of these nanostructures can be a tedious process. Researchers focus on nanocrystals that independently form complex structures without any external influence, for example by sticking together (assembling). This increases their effectiveness in important technological applications, such as green energy generation or sensor technology.
“Often nanoparticles arrange themselves independently, as if following a blueprint, and take on new shapes,” explains Lukas Grote, one of the main authors of the study and scientist at DESY and the University of Hamburg. “Now, however, we want to understand why they are doing this and what steps they go through on the way to their final form. That is why we follow the formation of nanomaterials in real time using high-intensity X-rays. ” For some of the experiments, the researchers used the European Synchrotron Radiation Facility (ESRF) and DESY’s synchrotron radiation source PETRA III.
Read more on the ESRF website
Image: X-rays from a synchrotron radiation source are both attenuated (absorbed) and deflected (scattered) by matter. Depending on which of these interactions is measured with a certain X-ray technology, conclusions can be drawn about different stages of the development process of a nanomaterial. If you combine both X-ray absorption and X-ray scattering, you can decipher all the steps from the starting material (left) to the fully assembled nanostructures (right).
Credit: Nature Communications