Physics of Energy Conversion and Storage (ECS), Physik-Department , Technical University of Munich , James-Franck-Str. 1 , 85748 Garching , Germany.
Nanosystems Initiative Munich (NIM) , Schellingstraße 4 , 80799 Munich , Germany.
ACS Appl Mater Interfaces. 2018 Jun 27;10(25):21688-21695. doi: 10.1021/acsami.8b03846. Epub 2018 Jun 13.
Development of efficient schemes of energy storage is crucial for finding a solution for the "generation versus consumption" problem. Aqueous Na-ion batteries have been already recognized as one of the promising candidates for large-scale energy-storage systems. Despite noticeable progress in this field, the actual intercalation mechanisms governing these battery cells are yet to be fully comprehended. In this manuscript, we examine the electrode/electrolyte interface formed between electrodeposited NaCo[Fe(CN)] films and aqueous solutions. The investigated systems exhibit up to three potentials of maximum entropy (PMEs). To the best of our knowledge, the existence of multiple PMEs in electrochemical systems has never been reported in the literature. These unexpected results are, however, in line with the theory explaining the correlation between the water structure at the interface and the ease of the interfacial mass and charge transfer. Additionally, the obtained PMEs appear to largely depend on the anions' properties, most probably on the hydration energy of these species. This reveals the impact of the electrolyte composition on the interfacial processes in Na-ion batteries.
发展高效的储能方案对于解决“发电与用电”问题至关重要。水系钠离子电池已被认为是大规模储能系统的有前途的候选者之一。尽管在这一领域已经取得了显著的进展，但这些电池的实际嵌入机制仍有待完全理解。在本文中，我们研究了电沉积的 NaCo[Fe(CN)]薄膜与水溶液之间形成的电极/电解质界面。所研究的系统表现出高达三个最大熵电位（PME）。据我们所知，电化学系统中存在多个 PME 在文献中从未有过报道。然而，这些意外的结果与解释界面上水结构与界面质量和电荷转移难易程度之间相关性的理论相符。此外，获得的 PME 似乎在很大程度上取决于阴离子的性质，很可能取决于这些物种的水合能。这揭示了电解液成分对钠离子电池界面过程的影响。
