Nanoporous Iridium Nanosheets for Polymer Electrolyte Membrane Electrolysis
Nanoporous Iridium Nanosheets for Polymer Electrolyte Membrane Electrolysis
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DOI：
10.1002/aenm.202101438
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发表时间：
2021-07-21
影响因子：
27.8
通讯作者：
Snyder, Joshua
中科院分区：
文献类型：
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作者：
Chatterjee, Swarnendu;Peng, Xiong;Snyder, Joshua
氢经济的增长是基于电化学能源技术的进步，而水电解是技术组合的关键组成部分。聚合物电解质膜水电解槽（PEMWE）阳极催化剂的开发主要集中在活性上，活性受组分和形态对反应物/中间体/产物吸附的影响。然而，这种策略的有效性被发现受到这些材料集成到PEMWE膜电极组件（MEA）的限制。无论催化剂活性如何，电极不均匀性、离聚体集成度和氧化物-氧化物界面高密度的结合都会导致与催化电极导电性差相关的显著性能损失。在这里，通过开发由纳米多孔Ir纳米片（npIr(x)-NS）组成的独特催化剂形态，解决了许多这些限制，与商业IrO2纳米颗粒催化剂相比，npIr(x)-NS在阳极析氧反应中表现出高的催化活性和优越的电极电子导电性。通过将npIr(x)-NS掺入到PEMWE mea中，其性能超过了商业催化剂涂层膜，负载低至0.06 mg(Ir) cm(-2)，而在5万次加速应力测试循环后表现出可忽略不计的性能损失。
The growth of the hydrogen economy is predicated on advancements in electrochemical energy technologies, with water electrolysis as a key component to the technological portfolio. Much of the focus on anode catalyst development for polymer electrolyte membrane water electrolyzers (PEMWE) is centered on activity as controlled by compositional and morphological impacts on reactant/intermediate/product adsorption. However, the effectiveness of this strategy is found to be limited upon integration of these materials into PEMWE membrane electrode assemblies (MEA). Regardless of catalyst activity, the combination of electrode inhomogeneity, ionomer integration, and high density of oxide-oxide interfaces yields significant performance losses associated with poor catalytic electrode conductivity. Here many of these limitations are addressed through the development of a unique catalyst morphology composed of nanoporous Ir nanosheets (npIr(x)-NS) that exhibit high catalytic activity for the anodic oxygen evolution reaction and superior electrode electronic conductivity in comparison to a commercial IrO2 nanoparticle catalyst. The utility of the npIr(x)-NS is demonstrated through incorporation into PEMWE MEAs where their performance exceeds that of commercial catalyst coated membranes at loadings as low as 0.06 mg(Ir) cm(-2) while exhibiting a negligible loss in performance following 50 000 accelerated stress test cycles.