General Synthesis of Sulfonate-Based Metal-Organic Framework Derived Composite of MxSy@N/S-Doped Carbon for High-Performance Lithium/Sodium Ion Batteries

A general and simple strategy is realized for the first time for the preparation of metal sulfide (MxSy) nanoparticles immobilized into N/S co-doped carbon (NSC) through a one-step pyrolysis method. The organic ligand 1,5-naphthalenedisulfonic acid in the metal-organic framework (MOF) precursor is used as a sulfur source, and metal ions are sulfurized in situ to form MxSy nanoparticles, resulting in the formation of MxSy/NSC (M=Fe, Co, Cu, Ni, Mn, Zn) composites. Benefiting from the MxSy nanoparticles and conductive carbon, a synergistic effect of the composite is achieved. For instance, the composite of Fe7S8/NSC as an anode displays excellent long-term cycling stability in lithium/sodium ion batteries. At 5 A g(-1), large capacities of 645 mA h g(-1) and 426.6 mA h g(-1) can be retained after 1500 cycles for the lithium-ion battery and after 1000 cycles for the sodium-ion battery, respectively.