以往，普魯士藍類似物因為結構穩定性和容許多種過渡元素置換的特性，常用作製造其他材料的前驅物，然而多元素普魯士藍類似物也能在能源應用上有出色的表現。我們利用簡單且低耗能的共沉澱法合成多元素普魯士藍類似物，並且應用於析氧反應電催化劑和鈉離子電池正極材料。在電催化劑的應用上，鎳鐵鈷普魯士藍類似物在鹼性環境下藉由多元素的協同作用展現絕佳的催化效果，僅需236 mV的過電壓即可達到10 mA/cm2的電流密度且在75小時後仍能保持穩定的催化效果。此外，普魯士藍類似物作為催化劑的相轉變也在本研究證實。
在鈉離子電池的應用上，普魯士藍類似物作為一種新興的電極材料，過去研究提出結構的缺陷和含水量對電池性能產生負面的影響。因此，我們藉由製程的改善合出具有高結晶度的多元素普魯士藍類似物，製程C的PBA具有比電容量110 mAh/g，在100 mA/g下200次充放電後仍然保有83%的比電容量保持率，且在300 mA/g的高電流密度下仍能維持84%的倍率性能。此次研究藉由結合不同元素的優勢和結構中成分的改善，製作鈉離子電池在各方面皆表現出色的正極材料。

Multi-element Prussian blue analogues perform well in many energy applications. Here, we synthesized multi-element Prussian blue analogues by a simple and low-energy co-precipitation method and applied them to oxygen evolution reaction electrocatalysts and cathode materials for sodium-ion batteries. In the application of electrocatalysts, NiFeCo-PBA exhibits excellent catalytic effects through the synergistic effect of multiple elements in an alkaline environment and only needs an overpotential of 236 mV to reach a current density of 10 mA/cm2 and keep stable catalytic ability. In addition, the phase transition of Prussian blue analogues as catalysts was also confirmed in this study. In the application of sodium-ion batteries, Prussian blue analogues are potential electrode material, and past studies have suggested that structural defects and water content have a negative impact on battery performance. Therefore, we synthesized a multi-element Prussian blue analogue with high crystallinity through the improvement of the process. The PBA of process C has a specific capacity of 110 mAh/g, which still retains 83% after 200 cycles at 100 mA/g. Moreover, 84% rate capability can still be maintained at high current density of 300 mA/g. In this study, by combining the advantages of different elements and the improvement of the composition in the structure, cathode material that outperforms in all aspects of sodium-ion battery is produced.

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