In the Realm of Radiation
Researchers at a new research lab operated by the Helmholtz Zentrum Berlin (HZB) and Freie Universität Berlin aim to gather new insight into the structure and dynamics of liquids and materials in solution.
Aug 28, 2012
From a distance, it looks like a UFO has landed right in the middle of the growing Adlershof technology park. Nearly round and silver, it sits amid spacious fields and lawns, the building housing the Helmholtz Zentrum Berlin für Materialien und Energie (HZB). BESSY II is the name of this electron storage ring, where the elemental particles of our matter are accelerated to near light speed and driven around in a circle. The process generates light across a broad spectrum of wavelengths, dubbed “synchrotron radiation.” This includes high-intensity X-rays, but also visible light as well as Terahertz radiation. At times the light is millions of times brighter than the sun.
Just recently, the facility established a new lab that offers the scientists innovative opportunities for research on materials. In close cooperation with each other, researchers from HZB and the Department of Physics at Freie Universität aim to gather new insight into liquids and “interfaces” – such as those between two liquids that cannot mix with each other. They are also working on studying the inner structure of water and proteins, as well as observing dynamics within these materials, including processes in which energy and charge are transferred from one molecule to a neighboring one.
To that end, the members of the 18-person junior research group “Structure and Dynamics of Functional Materials in Solution” conduct their experiments at two locations at once. Half of the lab is located in Adlershof, while the other half is at the Department of Physics at Freie Universität. While the group at BESSY II deals primarily with analyzing structures, the researchers at the university, in Berlin’s Dahlem district, aim to use advanced laser technology to study the dynamics of these structures.
The overall lab is headed by Emad Aziz, a professor at the Department of Physics at Freie Universität Berlin. When Aziz, a 33-year-old native of Egypt and naturalized German citizen, makes his way through the experimentation chambers, he is happy to see how “his project” is growing and thriving. “You’re real geniuses,” he praises his team.
Aziz and his team have about 3.5 million euros at their disposal for a period of five years. The majority of that amount comes from scientific awards Aziz has won along with funding secured from the Helmholtz Association and the European Union. “This lets us do our research under completely new conditions,” Aziz says. In the labs, liquids are analyzed using “soft” X-rays and extreme ultraviolet radiation – methods that have only been available to researchers for a few years. To do this, the liquid that is to be studied first has to be placed within a vacuum, with complex equipment being used to extract the air surrounding it. To keep the liquid itself from evaporating during this process, it is separated from the vacuum environment in a small through-flow cell with very thin membranes. It’s a tricky task, since the membrane must not be breached or damaged. Aziz and his team also recently began using a testing method that eliminates the need for these membranes. In this method, a thin, barely visible jet of the liquid is pumped into the vacuum chamber at high speed and then measured quickly, before the sample evaporates.
Researchers at the labs also study the properties of metal ions – electrically charged atoms or molecules of iron, copper, or cobalt, for instance – that have been dissolved in liquids. Among other things, the metal ions can be components of proteins, where they act as catalysts for biochemical reactions, thereby fulfilling key biological functions in the cells of the human body.
The materials scientists’ work is of tremendous importance in the energy sector and beyond. The researchers aim, for example, to find out whether the properties of solar cells vary depending on the method and materials used to make them. Their research might also yield new findings toward the development of hydrogen-fueled cars. Medical researchers also hope it will provide answers to questions that so far have been resolved only in part, if at all. The researchers face numerous challenges that can only be overcome through interdisciplinary teamwork. “Biologists have to work with physicists and chemists with medical researchers,” Aziz says with conviction.
Prof. Dr. Emad Aziz, Freie Universität Berlin, Department of Physics, Tel.: +49 (0)30 / 8062-15003, Email: email@example.com