Nickel-carbon nanorods as multifunctional separators for highly efficient and long-lived lithium sulfur batteries
Hexiang Xu, Lina Jin, Xinye Qian, Bo Li
Abstract
• A room-temperature, environmentally friendly strategy was developed to synthesize Zn/Ni-MOF precursors. • Zn/Ni-MOF was thermally transformed into hierarchical Ni-CNR structures with uniformly dispersed Ni nanoparticles. • The Ni-CNR composite was served as a modification layer for the separator in Li-S batteries. • The Ni-CNR composite integrates physical confinement, chemical adsorption and catalytic conversion. To address the challenges of polysulfide shuttling and poor conductivity in lithium-sulfur batteries (LSBs), we developed nickel-embedded carbon nanorod composites (Ni-CNR) utilizing a green synthesis strategy. Room-temperature synthesized Zn/Ni-MOF precursors were thermally transformed into hierarchical Ni-CNR structures characterized by carbon nanorods featuring uniformly dispersed nickel nanoparticles. This unique architecture synergistically integrates physical confinement, with a surface area of 926 m 2 g −1 , chemical adsorption and catalytic conversion of polysulfides via metallic Ni active sites. When employed as a separator coating for polymer electrolytes (PE), the Ni-CNR modified cell exhibited exceptional electrochemical performance: an initial capacity of 998.8 mAh g −1 at a rate of 0.5C, with a retention rate of 45 % after 600 cycles; remarkably low charge transfer resistance measuring at 23.8 Ω; and stable operational sulfur loading maintained at 5 mg cm −2 . The scalable synthesis method leveraging MOF-derived carbon frameworks along with transition metal catalysis presents a cost-effective solution for practical LSB applications, merging environmental sustainability with high energy density retention.