Jacquemond Rémy Richard, van der Heijden Maxime, Boz Emre Burak, Carreón Ruiz Eric Ricardo, Greco Katharine Virginia, Kowalski Jeffrey Adam, Muñoz Perales Vanesa, Brushett Fikile Richard, Nijmeijer Kitty, Boillat Pierre, Forner-Cuenca Antoni
Electrochemical Materials and Systems, Department of Chemical Engineering and Chemistry, Eindhoven University of Technology, P.O. Box 513, 5600 MB, Eindhoven, The Netherlands.
DIFFER - Dutch Institute for Fundamental Energy Research, P.O. Box 6336, 5600 HH5612, Eindhoven, The Netherlands.
Nat Commun. 2024 Sep 5;15(1):7434. doi: 10.1038/s41467-024-50120-7.
The continued advancement of electrochemical technologies requires an increasingly detailed understanding of the microscopic processes that control their performance, inspiring the development of new multi-modal diagnostic techniques. Here, we introduce a neutron imaging approach to enable the quantification of spatial and temporal variations in species concentrations within an operating redox flow cell. Specifically, we leverage the high attenuation of redox-active organic materials (high hydrogen content) and supporting electrolytes (boron-containing) in solution and perform subtractive neutron imaging of active species and supporting electrolyte. To resolve the concentration profiles across the electrodes, we employ an in-plane imaging configuration and correlate the concentration profiles to cell performance with polarization experiments under different operating conditions. Finally, we use time-of-flight neutron imaging to deconvolute concentrations of active species and supporting electrolyte during operation. Using this approach, we evaluate the influence of cell polarity, voltage bias and flow rate on the concentration distribution within the flow cell and correlate these with the macroscopic performance, thus obtaining an unprecedented level of insight into reactive mass transport. Ultimately, this diagnostic technique can be applied to a range of (electro)chemical technologies and may accelerate the development of new materials and reactor designs.
电化学技术的持续进步需要对控制其性能的微观过程有越来越详细的了解,这激发了新型多模态诊断技术的发展。在此,我们介绍一种中子成像方法,以实现对运行中的氧化还原液流电池内物种浓度的空间和时间变化进行量化。具体而言,我们利用溶液中氧化还原活性有机材料(高氢含量)和支持电解质(含硼)的高衰减特性,对活性物种和支持电解质进行相减中子成像。为了解析电极上的浓度分布,我们采用面内成像配置,并通过不同操作条件下的极化实验将浓度分布与电池性能相关联。最后,我们使用飞行时间中子成像来解卷积运行过程中活性物种和支持电解质的浓度。通过这种方法,我们评估了电池极性、电压偏置和流速对液流电池内浓度分布的影响,并将这些与宏观性能相关联,从而获得了对反应性质量传输前所未有的深入了解。最终,这种诊断技术可应用于一系列(电)化学技术,并可能加速新材料和反应器设计的开发。