%0 Conference Paper
%A Hecker, Burkhard
%A Robens, Elisabeth
%A Kungl, Hans
%A Tempel, Hermann
%A Eichel, Rüdiger-A.
%T Tuning the Selectivity for the CO2 Reduction towards CO through specific Synthesis of Silver Catalysts with different Morphologies
%M FZJ-2022-03477
%D 2022
%X The aimed reduction of fossil carbon sources in our society does not only includes fossil fuels but also carbon-based chemicals for further production processes. A promising alternative source for these chemicals is the electrochemical reduction of carbon dioxide. By using electrical energy from renewable sources, this process can be ecologically and economically beneficial. [1,2]Depending on the cathode material and the local reaction environment, different reduction products of carbon dioxide are produced. Furthermore, hydrogen can evolve in a competitive reaction. Therefore, it is of great interest to develop cathode catalysts that show good selectivity for the desired products as well as high activity and stability during operation. [2,3]In our study, we compare the performance of four different silver materials by their respective activity and selectivity towards carbon monoxide, hydrogen and formate at different electrochemical potentials. The materials were synthesized by electroless silver deposition and intensively characterized by SEM, EDX, HR-TEM, XRD and Pb-UPD to gain information about the morphology on different scales. In the second step, the materials were tested as cathode catalysts during the CO2 reduction and the products were quantified via GC and IEC. It was shown, that silver materials containing more reactive edges and controlled orientations of their surface atoms are beneficial at high potentials and low current densities. On the other hand, at low potentials and high current densities, the mass transport gets more important leading to the increased formation of formate at silver materials at which the mass transport is limited in some regions.Our collected results thus show in detail how the electrochemical reaction is affected by the morphology of the synthesized silver structures. The gained knowledge is relevant not only for the production of carbon monoxide at silver cathodes but also for more complex reactions. For example, it is known that structures with limited mass transport can be beneficial for electrochemical reduction of carbon dioxide towards propanol at copper surfaces. [4] Therefore, the gained knowledge can be used to design and improve further catalyst materials.Literature:[1] Jordaan, Sarah M., Nature Catalysis 2021, 4.11, 915-920. [2] Garg, Sahil, Journal of Materials Chemistry A 8.4 (2020): 1511-1544. [3] Nwabara, Uzoma O., ChemSusChem 13.5 (2020): 855-875. [4] Zhuang, Tao-Tao, Nature Catalysis 1.12 (2018): 946-951.
%B GDCh Electrochemistry Berlin 2022
%C 27 Sep 2022 - 30 Sep 2022, Berlin (Germany)
Y2 27 Sep 2022 - 30 Sep 2022
M2 Berlin, Germany
%F PUB:(DE-HGF)24
%9 Poster
%U https://juser.fz-juelich.de/record/909864