High-performance hybrid supercapacitors based on MOF-derived hollow ternary chalcogenides

In-situ growth of hybrid nanostructures composed of hollow transition metal chalcogenides has attracted increasing attention for the fabrication of high-performance hybrid supercapacitors (HSCs). Herein, we report the binder-free design of hierarchical ternary Cu(Co-Ni)(2)S-4 nanotubes on nickel foam (Cu(Co-Ni)(2)S-4 NTs/Ni foam) using synchronous etching and multi-ion doping enabled metal-organic framework (MOF) precursors. The MOF-derived hollow structured Cu(Co-Ni)(2)S-4 NTs/Ni foam electrode unveils an excellent battery-type redox kinetics with highest areal and specific capacities of Q(ac): 382.1 mu Ah/cm(2) and Q(sc):181.9 mAh/g, respectively at a current density of 2 mA/cm(2) with good cycling stability in 1 M KOH electrolyte. With the large electroactive area and superior electrochemical conductivity, the hierarchical composite electrode offers much space to grasp huge volume of charges, thus enabling an excellent energy storage performance. By integrating battery-type Cu(Co-Ni)(2)S-4 NTs/Ni foam as a positive electrode with porous carbon as a capacitive-type electrode, a prototype HSC device is assembled. Along with high energy and power densities of 0.27 mWh/cm(2) and 21.75 mW/cm(2), the fabricated prototype device retains excellent cyclability with an energy efficiency of 95.8%. Capitalizing high energy storage properties of HSC, an assembled self-powered station consisting of HSC and solar cell further illustrates its practical applicability for renewable energy applications.

Automated summary

The study presents a novel electrode design of hierarchical Cu(Co-Ni)(2)S-4 nanotubes on nickel foam using synchronous etching and multi-ion doping. The electrode demonstrates excellent battery-type redox kinetics and cycling stability, achieving outstanding energy storage performance. By combining battery-type Cu(Co-Ni)(2)S-4 nanotubes/nickel foam with porous carbon as capacitive-type electrode, a high-performance hybrid supercapacitor (HSC) device with high energy efficiency and cyclic stability is assembled.