A Facilely Synthesized NiCo2S4 with Two Mutually Reinforcing Active Sites for High-Performance Lithium–Sulfur Batteries

• DOI: 10.1021/acsami.3c14520
• Publication Date: 2023-12-06T19:08:01Z
• Authors: Hongyuan Xu; Guanghui Xu; Shengjun Zhai; Siyu Jin; Yihong Tong; Zhao Kong; Jiawei Li; Hong Jin; Hui Xu
• Keywords: Cobalt sulfide

The shuttle effect and slow conversion kinetics of soluble polysulfides hinder the commercial application lithium-sulfur batteries (LSBs). In this context, we propose a three-dimensional lamellar-stacked nanostructure nickel cobalt sulfide (D-NiCo2S4) enriched with lattice defects by manipulating cations in spinel sulfides. It has an obvious synergistic promotion mechanism for adsorption catalysis lithium Specifically, Ni3+ on tetrahedral (Td) sites strong Ni-S covalency anchors LiPSs, whereas Co3+ octahedral (Oh) promotes highly efficient catalytic which is confirmed experimental results density functional theory (DFT) calculations. Besides, crystal distortions lamellar region could expose more active enhance redox reaction polysulfides. Hence, Li-S D-NiCo2S4@S as cathode show outstanding cycle stability; upon cycling at 1 A/g, battery achieves high initial specific capacity 1001.12 655.31 mAh g-1 after 1000 cycles (decay rate low 0.05% per cycle), well areal 3.15 cm-2 under S loading (4.2 mg cm-2). This work provides viable scheme designing bimetal catalysts furnishes rational strategy constructing LSB cathodes area capacity.