Insights into the hydrogen evolution reaction in vanadium redox flow batteries:A synchrotron radiation based X-ray imaging study

作     者：Kerstin Köble Alexey Ershov Kangjun Duan Monja Schilling Alexander Rampf Angelica Cecilia TomášFaragó Marcus Zuber Tilo Baumbach Roswitha Zeis Kerstin Köble;Alexey Ershov;Kangjun Duan;Monja Schilling;Alexander Rampf;Angelica Cecilia;Tomáš Faragó;Marcus Zuber;Tilo Baumbach;Roswitha Zeis

作者机构：Helmholtz Institute UlmKarlsruhe Institute of Technology89081 UlmGermany Laboratory for Applications of Synchrotron RadiationKarlsruhe Institute of Technology76131 KarlsruheGermany Institute for Photon Science and Synchrotron RadiationKarlsruhe Institute of Technology76344 Eggenstein-LeopoldshafenGermany Department of ElectricalElectronicsand Communication EngineeringFaculty of EngineeringFriedrich-Alexander-Universität Erlangen-Nürnberg(FAU)91058 ErlangenGermany Department of Mechanical and Industrial EngineeringUniversity of TorontoToronto M5S 3G8OntarioCanada 

出 版 物：《Journal of Energy Chemistry》 (能源化学（英文版）)

年 卷 期：2024年第91卷第4期

页      面：132-144页

核心收录：

学科分类：081704[工学-应用化学] 0808[工学-电气工程] 08[工学] 0817[工学-化学工程与技术] 

基　　金：financial support through a KekuléPh.D.fellowship by the Fonds der Chemischen Industrie(FCI) support from the China Scholarship Council(No.202106950013) 

主　　题：Vanadium redox flow battery Synchrotron X-ray imaging Tomography Hydrogen evolution reaction Gas bubbles Deep learning 

摘      要：The parasitic hydrogen evolution reaction(HER)in the negative half-cell of vanadium redox flow batteries(VRFBs)causes severe efficiency ***,a deeper understanding of this process and the accompanying bubble formation is *** benchmarking study locally analyzes the bubble distribution in thick,porous electrodes for the first time using deep learning-based image segmentation of synchrotron X-ray *** large three-dimensional data set was processed precisely in less than one minute while minimizing human errors and pointing out areas of increased HER activity in *** study systematically varies the electrode potential and material,concluding that more negative electrode potentials of-200 m V *** hydrogen electrode(RHE)and lower cause more substantial bubble formation,resulting in bubble fractions of around 15%–20%in carbon felt ***,the bubble fractions stay only around 2%in an electrode combining carbon felt and carbon *** detected areas with high HER activity,such as the border subregion with more than 30%bubble fraction in carbon felt electrodes,the cutting edges,and preferential spots in the electrode bulk,are potential-independent and suggest that larger electrodes with a higher bulk-to-border ratio might reduce HER-related performance *** described combination of electrochemical measurements,local X-ray microtomography,AI-based segmentation,and 3D morphometric analysis is a powerful and novel approach for local bubble analysis in three-dimensional porous electrodes,providing an essential toolkit for a broad community working on bubble-generating electrochemical systems.