Data underlying the publication: Mapping Spatial and Temporal Electrochemical Activity of Water and CO2 Electrolysis on Gas-Diffusion Electrodes Using Infrared Thermography

Electrolysis of water, CO2, and nitrogen-based compounds presents the opportunity of generating fossil-free fuels and feedstocks at an industrial scale. Such devices are complex in operation, and their performance metrics are usually reported as electrode-averaged quantities. In this work, we report the usage of infrared thermography to map the electrochemical activity of a gas-diffusion electrode performing water and CO2 reduction. By associating the heat map to a characteristic catalytic activity, the presented system can capture electrochemical and physical phenomena as they occur in electrolyzers for large-scale energy applications. We demonstrate applications for catalyst screening, catalyst-degradation measurements, and spatial activity mapping for water and CO2 electrolysis at current densities up to 0.2 A cm–2. At these current densities we report catalyst temperature increases (&gt;10 K for 0.2 A cm–2) not apparent otherwise. Furthermore, substantial localized current density fluctuations are present. These observations challenge assumed local conditions, providing new fundamental and applied perspectives.<br>

水电解、二氧化碳（CO₂）及氮基化合物电解，具备工业规模制备无化石燃料与基础原料的潜力。此类电解装置运行机制复杂，其性能指标通常以电极平均量化参数的形式进行报道。本研究中，我们采用红外热成像（infrared thermography）技术，对参与水和二氧化碳（CO₂）还原反应的气体扩散电极（gas-diffusion electrode）的电化学活性进行空间成像测绘。通过将热图与特征催化活性建立关联，本系统可捕捉大规模能源应用电解槽中实时发生的电化学与物理过程。我们验证了该系统在催化剂筛选、催化剂降解表征，以及电流密度最高达0.2 A cm⁻²的水电解与CO₂电解空间活性测绘中的应用场景。在上述电流密度条件下，我们观测到催化剂的温度升高（0.2 A cm⁻²时温升超过10 K），此类温升通过常规检测手段难以被察觉。此外，系统还可捕捉到显著的局部电流密度波动现象。这些观测结果对现有既定的局部反应条件假设提出了挑战，为相关领域的基础研究与应用拓展提供了全新视角。