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The porous CoS 2 /nitrogen-doped carbon (CoS 2 -CN) polyhedrons were prepared using metal-organic framework as the precursor. After the carbonization of zeolitic imidazolate framework ZIF-67 and the heat treatment with sulfur, the CoS 2 -CN composite was obtained. Multi-walled carbon nanotubes (MWCNTs) were introduced and evenly intertwined with the CoS 2 -CN. Eventually, CoS 2 -CN and Co-CN exhibited good discharge capacities of 498.3 mAh/g and 402.2 mAh/g, respectively. For electrochemical hydrogen storage, more electrochemical active sites could be provided owing to the extra-ordinary porous nanostructure and large specific surface area inherited from ZIF-67. The N-doped carbon could enhance the conductivity of the materials. The CoS 2 -CN electrode revealed higher discharge capacity than Co-CN due to the introduction of sulfur species. Moreover, the discharge capacity further increased to 542.8 mAh/g for CoS 2 -CN/MWCNTs. The loaded MWCNTs could further enhance the conductivity and electrocatalytic activity of CoS 2 -CN. The high-rate dischargeability, kinetic properties and corrosion resistance were also improved after MWCNTs modification.

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