New in situ cell for investigating solid- and liquid-state samples and their interfaces under electrical voltage
Exploded view drawing of the electrochemical flow cell for soft x-ray absorption and emission spectroscopy. The membrane (yellow) is coated with a metal, serving as working electrode (WE) and that also serves as a support for the solid sample. Counter (CE) and reference electrode (RE) are placed in the liquid chamber. Tubes are attached to allow fast and easy liquid exchange and to prevent radiation damage.
© HZB
A team headed by Dr. Kathrin Aziz-Lange has developed a new in-situ cell for X-ray spectroscopy of fluid samples and their interfaces to solid bodies. What is special is the cell contains electrodes that can expose the sample to voltage during or between measurements. The resulting changes triggered in the electrical structure of the sample can be observed with the help of X-ray absorption and emission spectroscopy in real time.
Christoph Schwanke from the HZB Institute for Solar Fuels as well as Ronny Golnak and Dr. Jie Xiao from the HZB Institute for Methods of Material Development participated in the work.
“This new cell is interesting if you want to better understand the functioning of materials for catalytic processes, in electrolytic cells, or rechargeable batteries”, explains Kathrin Aziz-Lange. These kinds of materials play a large role in energy research, for instance in hydrogen generation through electrolytic splitting of water, in fuel cells, in dye-sensitised solar cells (DSSC) as well as in development of more efficient batteries.
The newly developed cell was presented in the scientific journal ,„Review of Scientific Instruments“ (5. November 2014, Vol. 85, 10). first results have already been obtained, and it can also be used by visiting researchers.
"Electrochemical flowcell for in-situ investigations by soft x-ray absorption and emission spectroscopy," has been published online today, 5 November 2014, in Review of Scientific Instruments (Vol.85, Issue 10).
DOI: 10.1063/1.4899063
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