Electrolysers offer an appealing technology for conversion of CO₂ into high-value chemicals. However, there are few tools available to track the reactions that occur within electrolysers. Here we report an electrolysis optical coherence tomography platform to visualize the chemical reactions occurring in a CO₂ electrolyser. This platform was designed to capture three-dimensional images and videos at high spatial and temporal resolutions. We recorded 12 h of footage of an electrolyser containing a porous electrode separated by a membrane, converting a continuous feed of liquid KHCO₃ to reduce CO₂ into CO at applied current densities of 50–800 mA cm⁻². This platform visualized reactants, intermediates and products, and captured the strikingly dynamic movement of the cathode and membrane components during electrolysis. It also linked CO production to regions of the electrolyser in which CO₂ was in direct contact with both membrane and catalyst layers. These results highlight how this platform can be used to track reactions in continuous flow electrochemical reactors.

电解槽提供了一种极具吸引力的技术，可将 CO ₂转化为高价值化学品。然而，很少有工具可用于跟踪电解槽内发生的反应。在这里，我们报告了一种电解光学相干断层扫描平台，用于可视化 CO ₂电解槽中发生的化学反应。该平台旨在以高空间和时间分辨率捕获三维图像和视频。我们记录了电解槽的 12 小时镜头，该电解槽包含由膜分隔的多孔电极，在 50–800 mA cm ^{-2的施加电流密度下将液体 KHCO} ₃的连续进料转化为 CO ₂还原为 CO 。该平台可视化反应物、中间体和产物，并捕获电解过程中阴极和膜组件惊人的动态运动。它还将CO 生产与电解槽区域联系起来，在该区域中CO ₂与膜层和催化剂层直接接触。这些结果强调了如何使用该平台来跟踪连续流电化学反应器中的反应。