Abstract
Endohedral metallofullerenes (EMFs) have been extensively studied due to their unique structural characteristics and physiochemical properties. Over the past three decades, researchers have developed different methods for the synthesis of endohedral metallofullerenes, including the Krätschmer-Huffman DC arc-discharge, laser ablation, radio frequency furnace, ion bombardment, and hot-atom chemistry method et al. Among them, DC arc-discharge method is the most popular technique used to date, since it enables the macroscopic synthesis of fullerenes species in a relatively simple and cost-effective way. With the application and modification of this method, metallofullerenes and endohedral clusterfullerenes with variable clusters encapsulated inside different cages have been synthesized and isolated. Besides, the laser ablation method still plays an important role on the investigation of endohedral fullerene formation mechanism. Separation methods also play key role in the preparation of novel endohedral fullerenes, as the soot extract obtained from DC arc-discharge method often contains a large variety of different fullerene species. High-performance liquid chromatography (HPLC) is widely used for the separation and purification of EMFs as it can yield highly purified EMFs with variable HPLC columns and recycling techniques applied. However, it is also known for its time-consuming procedures and is only suitable for samples on milligram scale. Thus, various nonchromatographic strategies have been developed for simpler and more efficient separation procedure, such as chemical and electrochemical methods. This chapter provides a detailed and comprehensive overview of the synthetic methods of EMFs and highlights the recent development in this field, followed by a summarization of different separation and purification methods.
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Chen, N., Zhuang, J., Li, X., Jin, M. (2021). Preparation of Endohedral Metallofullerenes. In: Lu, X., Akasaka, T., Slanina, Z. (eds) Handbook of Fullerene Science and Technology. Springer, Singapore. https://doi.org/10.1007/978-981-13-3242-5_26-1
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