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DOI	10.1039/c8ee01192c
	The balance of electric field and interfacial catalysis in promoting water dissociation in bipolar membranes
	Yan Z.; Zhu L.; Li Y.C.; Wycisk R.J.; Pintauro P.N.; Hickner M.A.; Mallouk T.E.
发表日期	2018
ISSN	17545692
起始页码	2235
结束页码	2245
卷号	11 期号:8
英文摘要	The lamination of a cation exchange layer (CEL) and an anion exchange layer (AEL) to form a hybrid bipolar membrane (BPM) can have several unique advantages over conventional monopolar ion exchange membranes in (photo-)electrolysis. Upon application of a reverse bias, the ordinarily slow water dissociation reaction at the AEL/CEL junction of the BPM is dramatically accelerated by the large electric field at the interface and by the presence of catalyst in the junction. Using electrochemical impedance spectroscopy (EIS), we have found a counterbalanced role of the electric field and the junction catalyst in accelerating water dissociation in a BPM. Experimental BPMs were prepared from a crosslinked AEL and a Nafion CEL, with a graphite oxide (GO) catalyst deposited at the junction using layer-by-layer (LBL) assembly. BPMs with an interfacial catalyst layer were found to have smaller electric fields at the interface compared to samples with no added catalyst. A comprehensive numerical simulation model showed that the damping of the electric field in BPMs with a catalyst layer is a result of a higher water dissociation product (H+/OH-) flux, which neutralizes the net charge density of the CEL and AEL. This conclusion is further substantiated by EIS studies of a high-performance 3D junction BPM that shows a low electric field due to the facile catalytic generation and transport of H+ and OH-. Numerical modeling of these effects in the BPM provides a prescription for designing membranes that function at lower overpotential. The potential drop across the synthetic BPM was lower than that of a commercial BPM by more than 200 mV at >100 mA cm-2 reverse bias current density, with the two membranes having similar long-term stability. © 2018 The Royal Society of Chemistry.
英文关键词	Catalysts; Dissociation; Electric fields; Electrochemical impedance spectroscopy; Graphene oxide; Ion exchange; Membranes; Numerical models; Anion exchange layer; Bipolar membranes; Catalyst layers; Cation exchange layer; Layer-by-layer assemblies; Long term stability; Net charge densities; Water dissociation; Ion exchange membranes; catalysis; catalyst; electric field; electrokinesis; ion exchange; layer; membrane; numerical model
语种	英语
来源期刊	Energy & Environmental Science
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/190164
作者单位	Departments of Chemistry, Biochemistry and Molecular Biology, and Physics, Pennsylvania State University, University Park, PA 16802, United States; Department of Materials Science and Engineering, Pennsylvania State University, University Park, PA 16802, United States; Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, TN 37235, United States
推荐引用方式 GB/T 7714	Yan Z.,Zhu L.,Li Y.C.,et al. The balance of electric field and interfacial catalysis in promoting water dissociation in bipolar membranes[J],2018,11(8).
APA	Yan Z..,Zhu L..,Li Y.C..,Wycisk R.J..,Pintauro P.N..,...&Mallouk T.E..(2018).The balance of electric field and interfacial catalysis in promoting water dissociation in bipolar membranes.Energy & Environmental Science,11(8).
MLA	Yan Z.,et al."The balance of electric field and interfacial catalysis in promoting water dissociation in bipolar membranes".Energy & Environmental Science 11.8(2018).