Rational design of a multidimensional N-doped porous carbon/MoS2/CNT nano-architecture hybrid for high performance lithium–sulfur batteries

Abstract

Exploring a stable and high-efficiency sulfur cathode with strong polarity and a robust porous conductive framework is a critical challenge to develop advanced lithium–sulfur (Li–S) batteries. Herein, a multidimensional N-doped porous carbon/MoS₂/CNT (FSC/MoS₂/CNT) nano-architecture hybrid is rationally designed and successfully fabricated by the facile pyrolysis and hydrothermal processes. For the nano-architecture composite, the porous carbon embedded with electroconductive acid-treated CNTs effectively enhances the flexibility and constructs a conductive network for rapid ion/electron transfer; specifically, a synergistic action of polar MoS₂ and electronegative doped N atoms significantly strengthens the chemical affinity with polysulfides; furthermore, MoS₂ exhibits a strong catalytic effect that can improve the redox kinetics of polysulfides. On account of the merits mentioned above, the as-built N-doped porous carbon/MoS₂/CNTs@S (FSC/MoS₂/CNTs@S) composite, utilized as the Li–S battery cathode, delivers a high discharge capacity of 1313.4 mA h g⁻¹ at 0.1C, glorious rate performance with 671.6 mA h g⁻¹ at 2.0C and remarkable cycling stability with a capacity fading rate of 0.059% per cycle for 500 cycles at 1.0C. This work provides a novel and simple strategy to design a CNT decorated polar and conductive hybrid network of doped porous carbon/transition metal sulfide for application in excellent performance Li–S batteries and numerous energy storage fields.