Physical chemistry of atmosphere

Cover of the Journals Analytical & Bioanalytical Chemistry (October 2022)
Cover of The Journal of Physical Chemistry A (May 2022)

Our research focusses on the impact of the atmosphere on various materials and the impact of various materials on the atmosphere. One way materials can influence the atmosphere is by triggering heterogeneous ice nucleation. Pure water will not freeze at 0°C but at temperatures below, depending on its volume. For small droplets, as they are present in the atmosphere, this will not happen at temperatures warmer than -36°C. Particles in the atmosphere show a very rich variability, with every particle being quite unique in its combination of size, form, and composition. Many of these particles are ice nucleation active, meaning they are able to trigger ice nucleation at warmer temperatures, closer to 0°C. Since ice cloud formation plays a huge role in our climate, it is important to understand what substances can be ice nucleation active, how they can be distributed, what lifespan they will have, and how the underlying processes work.
Every material that is in exposed to the atmosphere experiences aging. The severity of this aging is depending on the material. The factors hereby are often not well understood. Especially for working materials like road pavement, these aging processes can be crucial and small changes in the material can make the difference of many years in the lifespan.

Hinrich Grothe and his team sitting on stairs