Producing High Concentrations of Hydrogen in Palladium via Electrochemical Insertion from Aqueous and Solid Electrolytes,Chemistry of Materials

当前位置： X-MOL 学术 › Chem. Mater. › 论文详情

Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)

Producing High Concentrations of Hydrogen in Palladium via Electrochemical Insertion from Aqueous and Solid Electrolytes
Chemistry of Materials ( IF 7.2 ) Pub Date : 2019-05-22 00:00:00 , DOI: 10.1021/acs.chemmater.9b01243
Jesse D. Benck ₁ , Ariel Jackson ₁ , David Young ₁ , Daniel Rettenwander ₁ , Yet-Ming Chiang ₁

Affiliation

Metal hydrides are critical materials in numerous technologies including hydrogen storage, gas separation, and electrocatalysis. Here, using Pd–H as a model metal hydride, we perform studies of electrochemical insertion of hydrogen into palladium via three different electrolyte media, aqueous liquid, polymeric solid, and ceramic solid electrolytes, from a gas phase source at 1 atm pressure. We show that the compositions achieved result from a dynamic balance between the rates of hydrogen insertion and evolution from the Pd lattice, the combined kinetics of which are sufficiently rapid that operando experiments are necessary to characterize the instantaneous PdH_x composition. Therefore, we use simultaneous electrochemical insertion and X-ray diffraction measurements, combined with a new calibration of lattice parameter versus hydrogen concentration, to accurately quantify the PdH_x composition. Furthermore, we show that the achievable hydrogen concentration is severely limited by electrochemomechanical damage to palladium and/or the substrate and that such damage is minimized by a combination of thin palladium films and compliant substrates. Under optimal conditions, we reach a maximum hydrogen concentration of x = 0.96 ± 0.02. The understanding embodied in these results helps to establish new design rules for achieving high hydrogen concentrations in metal hydrides.

中文翻译：

通过水和固体电解质的电化学插入产生高浓度的钯氢

金属氢化物是包括氢存储，气体分离和电催化在内的众多技术中的关键材料。在这里，我们以Pd–H作为模型金属氢化物，通过1 atm压力下的气相源，通过三种不同的电解质介质（含水液体，聚合物固体和陶瓷固体电解质）将氢电化学插入钯中的研究。我们表明，所获得的组成是由于氢的插入速率与Pd晶格的析出之间的动态平衡而产生的，该动力学的组合动力学足够快，以至于需要进行操作实验来表征瞬时PdH _x。作品。因此，我们同时进行电化学插入和X射线衍射测量，并结合晶格参数对氢浓度的新校准，以准确地量化PdH _x组成。此外，我们表明可实现的氢浓度受到对钯和/或基底的电化学机械损伤的严重限制，并且通过薄的钯膜和顺应性基底的组合将这种损伤最小化。在最佳条件下，我们达到的最大氢浓度为x = 0.96±0.02。这些结果所体现的理解有助于建立新的设计规则，以实现金属氢化物中高氢浓度。

更新日期：2019-05-22

点击分享查看原文

点击收藏

公开下载

阅读更多本刊新发论文本刊介绍/投稿指南