Bimetallic nanoparticles decorated porous carbon as the host material to enhance the performance of lithium-sulfur batteries

Lithium-sulfur battery (LSB) is one of the most appealing candidates for advanced next-generation electrochemical energy storage systems based on the merits of extraordinary theoretical specific energy density, abundant resources and environmental friendliness of sulfur. However, the ‘‘shuttle effect” of lithium polysulfides (LiPSs) and low utilization of sulfur cathode severely plague the large-scale commercialization of the LSBs. In this work, a novel host material for sulfur cathode, namely porous carbon (PC) decorated with NiCo2O4 nanoparticles (NiCo2O4/PC), was designed and prepared. Among all tested NiCo2O4 nanoparticles with different morphologies, the NiCo2O4 nanoparticles with honeycomb pore shape (C-NiCo2O4) showed excellent performance as sulfur cathode host. Benefiting from the synergistic advantages between PC and C-NiCo2O4 nanoparticles, the C-NiCo2O4/PC host materials showed strong adsorption for LiPSs, promising the alleviation of shuttle effect and promoting the catalytic conversion process of LiPSs. As a result, the LSBs with [email protected]2O4/PC cathode delivered a high specific capacity of 1065.2 mAh g−1 at 0.1C, a stable cycling over 500 cycles with low fading rate of 0.053% per cycle at 0.5C and an enhanced rate capability compared with those of [email protected]2O4 and [email protected] cathodes. This work demonstrated the synergistic effect of physical shackle from PC and adsorption-catalysis from NiCo2O4 nanoparticles, which might provide new insights into the optimization of carbonaceous architecture for rationally regulating the polysulfide redox reactions.