Laboratory of Environmental Chemistry
The surface chemistry research group investigates multi-phase chemical processes relevant for atmospheric chemistry and the analytical chemistry research group reconstructs environmental and climatic conditions from high-altitude glaciers.
The Latest News
Welcome Yohei Uemura
We warmly welcome Yohei Uemura as Postdoc in the Laboratory of Environmental Chemistry. He joined the Surface Chemistry group on 1 July 2019.
Yohei Uemura got his master and PhD degree in chemistry at the University of Tokyo. He has then continued on an academic career path at different universities in Japan and last at Utrecht University in the Netherlands. His speciality is the application of fast and ultrafast X-ray absorption spectroscopy techniques to follow the chemical dynamics of reactions. At PSI, Yohei Uemura will study the photolysis of organo-iodide compounds and the fate of primary and secondary iodine products in aqueous solutions at the SwissFEL and the SuperXAS beamline.
Welcome Petr Nalivaika
A warm welcome to Petr Nalivaika, our new PhD student in the Laboratory of Environmental Chemistry! He started working in the Analytical Chemistry group on 1 April 2019.
Petr obtained his master in Analytical Chemistry from the McMaster University, Hamilton, Canada. During his master thesis he investigated structured conductive probes for mass spectrometry.
Petr will work on the reconstruction of heavy metal pollution for the region of the former Soviet Union (FSU) for the past ~7000 years using ice cores from study sites in the Siberian and Mongolian Altai. His thesis work is part of the SNF funded project entitled “Reconstructing historic and modern anthropogenic FSU heavy metal pollution”.
Welcome Yanisha Manoharan
Join me in welcoming Yanisha, our new PhD-student in Markus Ammann's group.
Yanisha got her master in chemistry at the university of Berne. During her master thesis, she worked on "Scanning tunneling microscopy and X-ray photoelectron spectroscopy study of a thioacetate-functionalized aromatic molecule on metal substrates”. At PSI, Yanisha Manoharan will be studying the kinetics of nitrate photochemistry in ice samples. Her thesis work is part of the SNF funded project entitled "Interfacial Chemistry of Ice: Photolysis and Acid-Base Equilibria in the QLL and Brine“.
Current Scientific Highlight
Why the Little Ice Age ended in the middle of the 19th century
In the first half of the 19th century, a series of large volcanic eruptions in the tropics led to a temporary global cooling of Earth's climate. That Alpine glaciers grew and subsequently receded again during the final phase of the so-called Little Ice Age was due to a natural process. This has now been proven by PSI researchers on the basis of ice cores.
Light from the particle accelerator helps to understand ozone decomposition
PSI researchers have developed an experimental chamber in which they can recreate atmospheric processes and probe them with unprecedented precision, using X-ray light from the Swiss Light Source SLS. In the initial experiments, they have studied the production of bromine, which plays an essential role in the decomposition of ozone in the lower layers of the atmosphere. In the future, the new experiment chamber will also be available for use by researchers from other scientific fields.
Coexistence of Physisorbed and Solvated HCl at Warm Ice Surfaces
The interfacial ionization of strong acids is an essential factor of multiphase and heterogeneous chemistry in environmental science, cryospheric science, catalysis research and material science. Using Near Ambient Pressure X-ray Photoelectron (NAPP) spectroscopy, we directly detected a low surface coverage of adsorbed HCl at 253 K in both molecular and dissociated states and interpret the results as physisorbed molecular HCl at the outermost ice surface and dissociation occurring upon solvation deeper in the interfacial region. This study gives clear evidence for nonuniformity across the air−ice interface and questions the use of acid−base concepts in interfacial processes.
The Latest Publications
A Holocene black carbon ice-core record of biomass burning in the Amazon Basin from Illimani, Bolivia
Climate of the Past 15, 579-592 (2019).DOI: 10.5194/cp-15-579-2019
A new method for the determination of primary and secondary terrestrial and marine biomarkers in ice cores using liquid chromatography high-resolution mass spectrometry
Talanta 194, 233-242 (2019).DOI: 10.1016/j.talanta.2018.10.042