Synthesis and Applications of Single-Chain Atomic Crystal, LiMo3Se3

Among the currently available low-dimensional nanomaterials, single-chain atomic crystals (SCAC) exhibit unique physical and chemical properties because of their one-dimensional atomic structure. SCAC is the isolated molecular chain unit from bulk 1D chained materials, in which weak van der Waals or ionic interactions stack together SCACs with strong intra-chain bonding. They have one-dimensional fibrous morphology and sub-nanometer scale diameter similar to conventional organic polymers. Furthermore, unlike conventional organic polymers that consist only of organic elements such as C, H, N, O, and S, SCACs are composed of inorganic elements, such as transition metal, chalcogen, and halogen. Therefore, SCACs have novel additional properties, such as electrical, optical, mechanical, and electrochemical properties that conventional organic polymers do not.To investigate the properties of isolated SCAC, the preparation of bulk single crystal with high crystallinity, and strategy for exfoliation are required. In this review, the studies on synthesis, exfoliation and applications of the representative SCAC, LiMo3Se3 are described. These results demonstrate that solution processed SCACs are promising building block for future application.