News & Press releases 2014
A closer look: How scientists visualize molecule interactions
So called "new" or functional materials often display special characteristics that are closely linked to their structure on the nano scale. The molecules in such materials can, for example, organize themselves, but can also be specifically stimulated by temperature or pH changes. Thus they are interesting candidates for applications such as organic solar cells or biosensors.
It is a major aim of research on new materials to understand and be able to control those characteristics. However, so far there were no infrared spectroscopy methods and analyses available that offer the necessary spatial and spectral resolution. This gap has now been closed by a team of researchers including Dr. Karsten Hinrichs from ISAS Berlin. A key role played the combination of the imaging technique called "infrared near field microscopy" which is developed in the group of Professor Markus B. Raschke at the University of Colorado in Boulder, USA, with infrared ellipsometry measurements at ISAS Berlin. In "Nature Communications" the scientists describe how they were able to gain unprecedented insights into local chemical environments of nanostructures such as the so called solvato-chromatic influence of neighboring molecules.
The paper titled "Vibrational nano-spectroscopic imaging correlating structure with intermolecular coupling and dynamics" (B. Pollard et al., Nat. Commun. 5, 3587) is available on the
> journal website.
New micro-spectroscopic methods at ISAS Berlin
ISAS Berlin has a new application lab: In a three-year project, ISAS scientists have developed novel micro-spectroscopic methods to characterize ultrathin layers with higher spectral range, resolution and sensitivity and time-dependent processes with better temporal resolution. The project titled "New concepts for vibrational spectroscopy on nanoscopic materials" was funded by the state Berlin from the European Funds for Regional Development (EFRE).
The scientists were able to set up a Raman microscope at ISAS that covers a much wider spectral area than similar commercialized devices. They also installed an infrared microscope that is now used to analyze ultrathin layers, such as in functional surfaces. Also, a novel Echelle spectrograph for parallel detection of the MIR spectrum (mid-infrared) was developed and successfully tested; it can be coupled to the microscope platform and provides a temporal resolution in the range of milliseconds.
This combination of methods will permit new applications in microfluidics and on biosensors as well as investigations on semiconductor nanostructures or the marker-free detection of organic molecules. The efficiency of the measure concepts has already been demonstrated on organic and anorganic nanofilms. Capturing extremely fast time-dependent processes is especially important for bioanalytics and ohysical chemistry.
In addition to applications in basic research, a commercialization of the measure concepts is planned.