A review of arc-discharge method towards large-scale preparation of long linear carbon chains

Linear carbon chains as new one-dimensional (1D) nanomaterials attract attention for the predicted outstanding properties. However, the high reactivity of linear carbon chains hampers further experimental research. To date, different methods have been developed to synthesize new materials containing linear carbon chains. Among them, the arc-discharge method is a practical way to prepare both finite and infinite linear carbon chains. This review provides a brief discussion of the recent progress in the techniques to prepare carbon chain-based materials and then focuses on the arc-discharge method. The configuration of apparatus, optimal conditions, and the corresponding mechanism of arc-discharge method to prepare long linear carbon chain inside multi-walled carbon nanotubes are summarized in detail. The characterization techniques are introduced to evaluate the quality of products. Moreover, remaining challenges and perspectives are presented for further investigation of long linear carbon chains.