Model-based kinetic analysis of O2 (ORR) and CO2 reduction (CO2RR)
In TP6 kinetics of oxygen (ORR) and carbon dioxide reduction (CO2R) on model silver electrodes are studied. The aim is to improve the basic understanding of the kinetics of electrochemical reactions under atypical conditions, e.g. in highly concentrated solutions (ORR) and in presence of side reactions (CO2R). Furthermore, this will contribute to comprehension of the limitations of ORR and CO2R in technical gas diffusion electrodes. The method of choice to study these processes is nonlinear frequency response analysis (NFRA). The ORR and CO2R reactions include the formation of intermediate (hydrogen peroxide) or by-products (H2) which reduce selectivity compared to the desired product (OH and CO for ORR or CO2R respectively). Therefore it is interesting to demonstrate whether periodic operation can influence product selectivity for CO2R, which is not only of practical but also of fundamental importance.