Colloidal Synthesis of NbS₂ Nanosheets: From Large-Area Ultrathin Nanosheets to Hierarchical Structures

Layered NbS₂, a member of group-V transition metal dichalcogenides, was synthesized via a colloidal synthesis method and employed as a negative material for a supercapacitor. The morphologies of NbS₂ can be tuned from ultrathin nanosheets to hierarchical structures through dynamics controls based on growth mechanisms. Electrochemical energy storage measurements present that the ultrathin NbS₂ electrode exhibits the highest rate capability due to having the largest electrochemical surface area and its efficient ion diffusion. Meanwhile, the hierarchical NbS₂ shows the highest specific capacitance at low current densities for small charge transfer resistance, displays 221.4 F g^-1 at 1 A g^-1 and 117.1 F g^-1 at 10 A g^-1, and cycling stability with 78.9% of the initial specific capacitance after 10,000 cycles. The aggregate or stacking of nanosheets can be suppressed effectively by constructing hierarchical structure NbS₂ nanosheets.