One-step hydrothermal synthesis of feather duster-like NiS@MoS 2 with hierarchical array structure for the Pt-free dye-sensitized solar cell

Novel feather duster-like nickel sulfide (NiS) @ molybdenum sulfide (MoS 2 ) with hierarchical array structure is synthesized via a simple one-step hydrothermal method, in which a major structure of rod-like NiS in the center and a secondary structure of MoS 2 nanosheets with a thickness of about 15–55 nm on the surface. The feather duster-like NiS@MoS 2 is employed as the counter electrode (CE) material for the dye-sensitized solar cell (DSSC), which exhibits superior electrocatalytic activity due to its feather duster-like hierarchical array structure can not only support the fast electron transfer and electrolyte diffusion channels, but also can provide high specific surface area (238.19 m 2 g −1 ) with abundant active catalytic sites and large electron injection efficiency from CE to electrolyte. The DSSC based on the NiS@MoS 2 CE achieves a competitive photoelectric conversion efficiency of 8.58%, which is higher than that of the NiS (7.13%), MoS 2 (7.33%), and Pt (8.16%) CEs under the same conditions. Graphical abstract Novel feather duster-like NiS@MoS 2 hierarchical structure array with superior electrocatalytic activity was fabricated by a simple one-step hydrothermal method.