Disintegrated carbon nanofibers derived from plasma treatment for highly stable sodium metal batteries

Carbon-based materials have been widely used in anodes for sodium metal batteries (SMBs). Surface modification of carbon-based materials is an effective method to improve the de-embedding behavior of sodium metal, which can increase the battery life, whereas SMBs need simpler and more efficient modification methods for practical-grade application. In this paper, novel disintegrated carbon nanofibers (D-CNFs) with rough surfaces were obtained by plasma treatment. D-CNFs exhibited highly reversible sodium deposition characteristics and were able to operate at a low polarization potential of 0.023 V for 800 h. The coulombic efficiency of the D-CNFs was stabilized above 97% after the third cycle. This excellent electrochemical performance is attributed to the disintegration of CNFs as a result of the plasma treatment. The CNFs expose richer vacancies, providing more active sites for sodium metal deposition. This implies that the prepared D-CNFs have better sodium storage properties. Meanwhile, this surface modification facilitates the further application of carbon-based materials in SMBs.