Interfacial Ice Chemistry

Photolysis and Acid-Base Equilibria in the QLL and Brine. The capability of acids to form hydrogen bonds has been found essential to their dissociation. The dissociation of acids plays is a principal process in the heterogeneous chemistry of the atmosphere. This project aims at developing a fundamental understanding of interfacial chemistry in the temperature range of -40°C to 0°C.  In the past, we have taken full advantage of our Near Ambient Pressure X-ray Photoemission and X-ray absorption spectroscopy in combination with classical flow tube studies to probe the adsorption of acidic trace gases to ice. Dissociation and photochemistry of nitric acid and nitrous acid at frozen and liquid air-water interfaces have long attracted scientific interest, most notably due to the pivotal role that this surface chemistry plays in modifying the nitrogen oxide budget and thus the oxidative capacity of the atmosphere.

Within a newly funded SNF project, we seek to develop a deeper understanding of acid-base chemistry and interplay with hydrogen bonds and solvation at the ice- and water-air interface. The research will explore the mechanisms of ammonia (NH₃) adsorption and proton transfer, focusing on how acidic adsorbents and reactive trace gases influence these processes. A central aim is to investigate molecular-level differences between air-water and air-ice interfaces. 

• Swiss National Science Foundation  10.007.211
• Swiss National Science Foundation: 178962
• Swiss National Science Foundation: 149629