Kira Henke


Investigation of Catalyst Deposition on Carbon Nanofibre Mats for CO2-Reduction Towards Formate

CV of electrolysis of CO2 with Sn-electrode & SEM image of SnO2 on CNF. Copyright: K. Henke CV of electrolysis of CO2 with Sn-electrode & SEM image of SnO2 on CNF.

Over the last few years, climate change and the resulting energy transition became highly discussed topics in politics and science. Wind and solar energy are intermittent power sources. Depending on the weather, in some periods, more power is generated than consumed. In other periods, more power is required than produced. Thus, the surplus power needs to be stored in order to compensate potential shortages in supply. A possible way to do so is the utilization of surplus power for the electrolysis of carbon dioxide (CO2). Thereby, the power is stored in value added chemicals such as carbon monoxide (CO), ethanol or formate. The selectivity towards a certain product of the CO2-reduction reaction (CO2RR) depends on the choice of catalyst material.

In this master thesis, tin and bimetallic tin-bismuth-catalysts will be examined with respect to their CO2RR-activity. Tin and bimetallic tin-bismuth-catalysts should possess a selectivity towards formate (HCOO-) production. The metal will be deposited as nanostructure on electrospun carbon nanofiber (CNF) mats and the resulting electrode will be used for the reduction of CO2. The way of deposition and the Faradaic efficiency of the formate production will be examined, establishing a convenient pathway for the reduction of CO2. The deposition methods are hydrothermal synthesis and electrodeposition of tin oxide or tin, respectively. The functionalized CNF mats are used as working electrodes in electrolytic measurements, which take place in an H-cell. The produced gases of the electrolysis are analysed via gas chromatography and the liquid formate via ion chromatography.