Manganese nitride/oxide heterostructure interlayer derived from triazolate metal-organic framework for stable Li-S batteries

The dissolving shuttle phenomenon of polysulfides (LiPSs) and their slow redox kinetics seriously restrict the further advancement of lithium-sulfur batteries (LSBs). In this work, manganese nitride/oxide heterostructure microsphere prepared by pyrolysis of triazolate metal-organic framework precursor was reasonably introduced into the interlayer material to achieve collaborative anchoring and catalytic effects on LiPSs. The adsorption, density functional theory (DFT) calculation, electrochemical and in situ Raman tests proves that the amorphous carbon coated heterostructures show good chemical affinity for LiPSs, which inhibits shuttle effect effectively and improves electrochemical conversion kinetics and energy efficiency. The LSBs equipped with manganese nitride/oxide interlayer exhibits an initial capacity of 1155.5 mAh/g and retains 631.3 mAh/g after 1000 cycles at 2C, corresponding to an average capacity decay of 0.045 % per cycle. In addition, despite the high loading (6.5 mg cm-2) and poor electrolyte conditions (E/S = 7.2 mL g-1), the battery cycle performance is still outstanding (734 mAh/g after 100 cycles at 0.5C). This work showcases the application of manganese nitride/ oxide heterogeneous catalysts in developing high-performance LSBs, thereby promoting the development of heterogeneous structures in electrochemical applications.