WS 2 @Co 9 S 8 @N/C core–shell as multifunctional electrocatalysts for dye-sensitized solar cell, oxygen reduction reaction and oxygen evolution reaction

It is promising strategy in recent years to design and prepare metal/carbon-based functional materials with different structures using metal–organic framework (MOF) composite precursors. Hollow multi-shell nanomaterials with large specific surface area and abundant active sites have become high energy conversion catalytic materials. The first prepared the transition metal chalcogenides of the nano-structure of the hollow core–shell and then grew the zeolitic imidazolate frameworks-67 in situ on the nanoparticles of core–shell. Then, through pyrolysis to obtain multilayer core–shell particles with porous outer shell of Co/N-doped carbon skeleton. WS 2 @Co 9 S 8 -2@N/C is applied in dye-sensitized solar cells as counter electrode material, showing good catalytic performance for I − / I 3 − redox reaction, and the power conversion efficiency is as high as 9.85%. As the electrode material of oxygen reduction reaction, the half-wave potential can reach E 1/2 = 0.855 V. For oxygen evolution reaction tests, there is a low overvoltage of 1.757 V when the current density is 10 mV cm −1 . In addition, the MOF can be grown in situ in different nanostructures, which can gain its advantages as a multifunctional material in terms of structure and multi-element, and this method can be applied to the fabricate of composite materials with different structures.