LAUSR

Abstract Polyynes and polyyne-based one-dimensional nanostructures are promising for several applications including ultra-compact circuits and electro-optical devices. A carbon arc in water is a simple method for synthesis of carbon nanostructure. Here we collected and analyzed the gas generated by a carbon arc in water, and unequivocally proved for the first time the presence of polyynes in the evolved gas. The discharge current is shown to regulate significantly the length distribution of polyynes, and the purity index and yield can be improved by appropriately raising the temperature. In addition, size-selected polyynes were obtained by high performance liquid chromatography separation and analyzed by surface-enhanced Raman scattering. This study provides a new route for the scalable preparation of gas containing polyynes with low cost and no pollution, and will broaden the potential application of polyynes.