Effect of mesoporous carbon microtube prepared by carbonizing the poplar catkin on sulfur cathode performance in Li/S batteries

A carbon microtube (CMT) was synthesized by carbonizing the poplar catkin and composited with sulfur, serving as a cathode for lithium/sulfur batteries. Scanning electron microscopy and energy dispersive spectroscopy mapping showed the formation of a tubular structure with uniform sulfur coating on the surface of CMTs. The CMT with a mesoporous surface is beneficial to both trapping soluble polysulfide intermediates and rendering the electrical conductivity of the prepared electrode. The resulting S/CMT composite cathode can deliver an 810 mAh g−1 reversible specific discharge capacity after 100 cycles at 0.1 C, and 585 mAh g−1 at 1 C.