Determining the structure of confined supercapacitor electrolytes

As electrochemical energy storage devices, electrical double layer (EDL) supercapacitors complement batteries since they are capable of substantially higher power densities. Energy in EDL supercapacitors is stored in the “double layer” of adsorbed ions on high surface area charged electrodes. However, despite its immense importance, the structure of EDL has never been measured in atomistic detail due to a lack of suitable methods. As a result, realistic predictive models for supercapacitors are notoriously absent. To address this, and as a first step towards developing operando studies of supercapacitor electrolyte structure, we will use NIMROD to study the structure of two supercapacitor electrolytes in the bulk and confined in a mesoporous carbon. We will use the power of neutrons to an utilise isotopic H/D substitution, and complimentary data refined simulation analysis, to reveal, in atomistic detail, how the structure of these important liquids changes in the presence of carbon electrode surfaces.

作为电化学储能器件，双电层（electrical double layer, EDL）超级电容器可补充电池的功能，因其具备显著更高的功率密度。EDL超级电容器中的能量存储于高比表面积带电电极上吸附离子形成的“双电层”中。然而，尽管其重要性极高，但由于缺乏合适的方法，EDL的结构从未被以原子级细节精度测定过。因此，超级电容器的真实预测模型长期以来一直缺失。为解决这一问题，并作为开展超级电容器电解质结构原位研究的第一步，我们将使用NIMROD研究两种超级电容器电解质在本体状态及受限在介孔碳中的结构。我们将利用中子的特性，结合同位素H/D取代技术与互补的数据精修模拟分析，以原子级细节揭示这些重要液体在碳电极表面存在时的结构变化。