普魯士藍類似物(Prussian blue analogues, PBAs)為一類結構類似普魯士藍的化合物，其大多數擁有普魯士藍安全且便宜的特性，因此常被科學家們應用在生醫、能源等領域。
而在本篇研究中，我們直接將鈷鐵普魯士藍(CoPB)酸蝕並加熱，成功以不使用保護劑的方法將其形貌從正立方體轉變為中空框架。且同時我們發現其結構往普魯士藍變化，產生了原本本屬於普魯士藍且CoPB 沒有的性質，如近紅外光區產生吸收。而我們也將錳鐵普魯士藍(MnPB)和鎳鐵普魯士藍(NiPB)進行同樣的反應，發現他們同樣會產生普魯士藍的性質，這讓我們產生興趣並嘗試推論出此機構。希望藉由了解此機構讓更多的PBAs 透過此反應獲得普魯士藍的特性，並產生新的應用。

Prussian blue analogues (PBAs) is a family of compounds which have similar structure to Prussian blue. Most of them are save and inexpensive just like Prussian blue. And many scientists have study their application about medical, energy, etc. So, we tried to modify PBAs structure and morphology to explore new realm of application.
In this study, we synthesized cobalt-iron Prussian blue (CoPB) first and treated it with HCl and acid directly. We can successfully get hollow-frame cobalt-iron Prussian blue (h-CoPB) without protecting agent in this method. Surprisingly, the structure of h-CoPB became Prussian blue-like structure. And it began behaving Prussian blue character which CoPB didn’t show. For instance, h-CoPB had near-infrared absorption. After that, we did same experiment for manganese-iron Prussian blue (MnPB) and nickel-iron Prussian blue (NiPB). And they also showed similar structure conversion phenomenon to CoPB. This result let us want to figure out the mechanism and find more PBAs can be endow Prussian blue character to expand their application potential.

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