Novel Ni/Ni2P@C hollow heterostructure microsphere as efficient sulfur hosts for high-performance lithium-sulfur batteries

• Published in: Journal of alloys and compounds 2021-08, Vol.871, p.159576, Article 159576
• Main Authors: Liu, Jiabing, Hu, Chenchen, Li, Haipeng, Baikalov, Nurzhan, Bakenov, Zhumabay, Zhao, Yan
• Format: Article
• Language: English
• Subjects: Batteries; Carbon; Carbon layer; Catalyzation; Chemical reactions; Electron transport; Energy storage; Heterostructure; Heterostructures; Lithium; Lithium sulfur batteries; Reaction kinetics; Rechargeable batteries; Storage batteries
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2021.159576

•Ni/Ni2P@C composite was prepared by a facile one-pot solvothermal approach.•The novel hollow sphere effectively relieve the volume expansion of sulfur.•The Ni/Ni2P heterostructure offers strong chemical bonding with lithium polysulfides.•The S/Ni/Ni2P@C electrode exhibits excellent cycling performance and rate capability. The authors demonstrate a novel Ni/Ni2P@C hollow heterostructure microsphere with Ni/Ni2P heterostructure wrapped in carbon layer and unique hollow structure as the functional sulfur host material for Li-S batteries. [Display omitted] Lithium-sulfur (Li-S) batteries present the potential viable rechargeable batteries in the field of energy-storage devices. However, the migration of lithium polysulfides (LiPSs) and slow electrochemical reaction kinetics are still the intractable problems on the development of Li-S batteries. Herein, novel Ni/Ni2P@C hollow heterostructure microsphere, as the functional sulfur host material, is prepared by a facile approach. The study found that the novel hollow microsphere composed of porous carbon layer alleviates the volume expansion effect and effectively improves the electron transport during cycling process. In addition, the Ni/Ni2P heterostructure wrapped in carbon layer not only improves the adsorption of LiPSs, but also catalyzes their conversion reactions. Therefore, Li-S batteries with the S/Ni/Ni2P@C electrode exhibit high discharge capacity of 1187.3 mAh g−1 at 0.2 C in the first cycle, notable rate capability of 716.9 mAh g−1 at 3 C and outstanding reversible capacity of 636.6 mAh g−1 over the 500 cycles at 1 C. Owing to these excellent electrochemical performances, the Ni/Ni2P@C hollow heterostructure microsphere has promising applications for Li-S batteries.