In-situ growth of graphene on carbon nanofiber from lignin

Design and synthesis of heterostructured carbon nanofibers is significant for applications in the field of optoelectronics , conductors and catalytic devices. Although lignin has been widely used as building blocks for fabricating nanofibers , it is still very challenging to synthesize conducting heterostructured carbon nanofibers without using additional catalysts. Herein, we first in-situ grew graphene grafted carbon nanofibers (G/CNFs) using calcium lignin sulfonate as starting materials without addition of catalysts. Through the electrospinning, pyrolysis and washing procedure, the as-spun nanofibers are converted into the flexible G/CNFs films. The in-situ formed CaS nanoparticles serve as catalysts for the growth of graphene on the surface of the CNFs, when the carbonization temperature is over 1100 °C. The as-prepared G/CNFs films exhibit superior electronic conductivity of 2377.9 S m −1 , which is comparable to the values reported in the literature. As a proof-of-concept, the as-fabricated lithium-sulfur battery exhibits a high discharge of 808.7 mAh·g −1 after 600 cycles at 0.2 C by using the G/CNFs membrane as stand-alone and flexible sulfur cathode scaffolds. This work represents a promising new approach for designing heterostructured graphene/CNFs using low-cost lignin precursors, and provides significant insights for the sustainable development of CNFs in numerous applications.