Angewandte Chemie International Edition · 2015 · 773 citations · 26 references
Natural SciencesMaterials EngineeringMaterials ScienceElectrochemistryFunctional MaterialsMaterials ChemistryBattery MaterialsCathode MaterialsElectrochemical Energy StorageElectrode MaterialsEnergy Storage MaterialsNanocompositesCarbon CompositesCarbon For Lithium-sulfur BatteriesCarbon Hosts For SulfurCarbon Nanomaterials For Energy StorageCarbon Nanotube Composite MaterialsCarbon Nanotube CompositesLithium-sulfur BatteriesSpherical Morphology
Despite the high theoretical capacity of lithium-sulfur batteries, their practical applications are severely hindered by a fast capacity decay, stemming from the dissolution and diffusion of lithium polysulfides in the electrolyte. A novel functional carbon composite (carbon-nanotube-interpenetrated mesoporous nitrogen-doped carbon spheres, MNCS/CNT), which can strongly adsorb lithium polysulfides, is now reported to act as a sulfur host. The nitrogen functional groups of this composite enable the effective trapping of lithium polysulfides on electroactive sites within the cathode, leading to a much improved electrochemical performance (1200 mAh g(-1) after 200 cycles). The enhancement in adsorption can be attributed to the chemical bonding of lithium ions by nitrogen functional groups in the MNCS/CNT framework. Furthermore, the micrometer-sized spherical structure of the material yields a high areal capacity (ca. 6 mAh cm(-2)) with a high sulfur loading of approximately 5 mg cm(-2), which is ideal for practical applications of the lithium-sulfur batteries.
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