Pomegranate-like conductive spherical composite as multifunctional cathode for high-performance lithium-sulfur battery
The commercialization of lithium-sulfur (Li–S) batteries can only be realized when the notorious polysulfide shuttle effect and sluggish redox reaction can be solved. Herein, we report a pomegranate-like microspheres material, which consist of Co nanoparticles embedded with N-doped carbon and interwoven by reduced graphene oxide (rGO) and carbon nanotubes (CNTs). The pomegranate-like composite, referred to as Co-NC@G-CNTs, formed by spray-drying and heat treatment, offers large surface area and highly porous feature that uniforms sulfur distribution and therefore facilitates polysulfide (LiPS) confinement. The three-dimensional conductive network created by Co nanoparticles and CNTs significantly enhances the ion/electron transportation within the electrode. Meanwhile, the decorated Co nanoparticles serve as active site that strengthens the chemical adsorption of LiPS. It also endows Co-NC@G-CNTs with promoted LiPS catalytic transformation. The study also highlighted that the introduction of CNTs in the microsphere is essential in enhancing the electrochemical performance of three-dimensional structured sulfur cathode. Attributed to these complementing features, the pomegranate-like Co-NC@G-CNTs composite exhibited a high initial specific capacity (1290 mAh g −1 at 0.2C), and an excellent rate performance (708 mAh g −1 at 3.0C). Moreover, the capacity at 1.0C faded at a rate of 0.058% per cycle over 500 cycles. The S/Co-NC@G-CNTs microspheres hold much potential for the development of Li–S batteries.
危险品化学品经营许可证（带存储）