Steady-state modeling of overvoltage on Ag-GDE during reduction reactions in aqueous electrolyte

子项目1的实验部分集中在制备特殊电极，该电极可以控制氧气还原和CO2电解过程中液体电解质和气体反应物之间的反应区域。此外，在新包括的CO2还原反应期间，电极结构和过电压之间的关系应在系统测量中量化。为此，需要改进的半电池设计。与TP 3 Roth和TP 7 Schuhmann一起，将确定CO2电解的实验数据。子项目1的理论部分集中于进一步改进GDE中电化学反应和传输过程耦合的定态模型。为此目的，将从TP 6 Vidakovic-Koch获得氧还原（以及随后的CO2还原）的更详细的本征动力学，而在TP 4 Manke中测量工作GDE中的真实的电解质分布，并在TP 5 Nieken中进行模拟。只有基于这些信息，才能开发出没有任何拟合参数的模型。还应使用TP 7 Schuhmann中的空间分辨测量值对模拟结果进行验证。最后，开发的稳态模型与TP 2 Krewer动态模型的可能组合将得到阐明。

The experimental part of sub-project 1 concentrates on the preparation of special electrodes with which the reaction zone between liquid electrolyte and gaseous reactants during oxygen reduction and CO2 electrolysis can be controlled. Furthermore, the relationship between electrode structure and overvoltage during the newly included CO2 reduction reaction shall be quantified in systematic measurements. For this purpose, an improved half cell design is required. Together with TP3 Roth and TP7 Schuhmann, the experimental data for the CO2 electrolysis will be determined.The theoretical part of sub-project 1 concentrates on the further improvement of the stationary model for the coupling of electrochemical reaction and transport processes in GDE. For this purpose, a more detailed intrinsic kinetics for oxygen reduction (and later also for CO2 reduction) will be obtained from TP6 Vidakovic-Koch while the real electrolyte distribution in the working GDE is measured in TP4 Manke and simulated in TP5 Nieken. Only based on this information can a model without any fitting parameters be developed. The simulated results shall also be validated with spatially resolved measurements in TP7 Schuhmann. Finally, the possible combination of the developed steady-state model with dynamic models from TP2 Krewer will be elucidated.