Preparation, Extraction/Isolation from Soot, and Solubility of Fullerenes

Abstract

The goal of this chapter is an overview of various methods used to prepare and extract fullerenes. With limits on cited references, this chapter cannot be a comprehensive review. We begin with a historical discussion surrounding their serendipitous discovery. Next, we introduce a variety of production methods, with each approach having its unique advantages and disadvantages. Regardless of the chosen synthesis, the generated soot represents a complex mixture of nanomaterials ranging from amorphous carbon to fullerenes to metallofullerenes, if metal is added to the plasma. During fullerene formation, the coproduction of structural isomers further complicates subsequent purification efforts. For this reason, the second half of this chapter describes efforts to simplify the complexity of soot extract based on some aspect of selectivity. Strategies to obtain specific types of fullerenes and metallofullerenes include soot extraction with selective solvents, solubility differences for fractional crystallization, electrochemical methods, and chemical derivatization to isolate otherwise unstable species. Further details describing the purification, characterization, and application development of fullerenes and metallofullerenes are located in other chapters. Herein, we primarily discuss key and seminal works - with a time line beginning with the birth of fullerene-containing soot, to the advent of new methods of synthesis, and concluding with strategies to selectively extract these carbon structures of wondrous molecular architectures that are fullerenes and endohedral metallofullerenes.