Electrochemical investigations are a very hot topic in basic and applied research. Recently, the world-wide trend of increasing energy consumption requires development of energy storage, e.g. high capacity and low-weight rechargeable batteries. Also in biochemistry or catalysis studies, electrochemistry is of great importance, to understand redox reactions and the behavior of catalysts. The combination of FTIR spectroscopy with electrochemistry offers insight in the molecular change and the reaction process of the studied molecules in addition to the electrochemical response of the experiment.
Fig. 1: Bruker’s reflection unit for electrochemical cells as left) purge version or right) vacuum version.With Bruker’s reflection unit for electrochemical cells both reflection measurements to monitor changes at the surface of the working electrode and ATR measurements for investigation of electrolytes can be applied. In case of the reflection unit for vacuum spectrometers the entire IR beam path is under vacuum. However, the user has full access to the electrochemical cell from top of the unit, where the cell is adapted, with no need to open the sample compartment and to break the vacuum. It provides users the possibility to refresh the electrolyte solution or the electrodes for repeated or series of measurements keeping other experimental and measurement conditions constant. Furthermore, a higher sensitivity and signal to noise ratio can be achieved using a vacuum spectrometer, especially in the finger print region, because of the absence of atmospheric disturbances.
In many electrochemical investigations fast electrochemical response and reaction kinetics are in the center of interest. To follow the fast potential steps and collect a FTIR spectrum at every applied potential value, just after equilibrium but before the potential is changed again for the next step, rapid scan is highly recommended and in many cases mandatory.
|Read the Application Note AN M125 In Situ FTIR Spectroelectrochemistry.|
|Read the Product Note PN M140 Reflection Unit prepared for Electrochemical Cell.|