Design and synthesis of 3D hierarchical NiMoS₄@CuCo₂S₄ array electrode with excellent electrochemical performance

Abstract

Large capacitance energy storage materials have a great application prospect due to the development of portable devices. An electrochemical deposition method was used to combine amorphous CuCo 2 S 4 with NiMoS 4 , which was prepared by a two-step hydrothermal method. The resulting grass-like nanowire array structure greatly promotes the utilization rate of active materials. By the addition of two variable valence metal ions, there is an increase in electrolyte touchable active sites and a decrease in the impedance of the electrode materials. Compared with bare NiMoS 4 , the binder-free composite electrode has a significantly better capacitance characteristic. In particular, the NiMoS 4 @CuCo 2 S 4 −8 has excellent capacity performance with a specific capacitance of 13.14 F cm −2 at the current density of 5 mA cm −2 . The electrode shows 73% capacitance retention after 2000 charge-discharge cycles. It is shown that the combined effect of the nanowires and the several variable valence metal ions is effective to increase the specific capacitance of bimetallic sulfides.

Role of binary metal chalcogenides in extending the limits of energy storage systems: Challenges and possible solutions

“…The all-solid-state asymmetric SC based on FeCo 2 S 4 @Ni(OH) 2 //rGO delivered a maximum energy density of 64 W h kg −1 , a maximum power density of 10.2 kW kg −1 and outstanding cycling performance (92.9% after 10,000 cycles). Moreover, compound composites of two dissimilar BMCs have also been developed as electrode to obtain satisfying capacitive performance [187,194,199,203,204,246,247]. For example, the nanotube-built multitripod arrays of dissimilar BMCs composite (FeCo 2 S 4 -NiCo 2 S 4 ) on a silver-sputtered textile cloth was fabricated [246].…”

Self-Assembled Hierarchical Silkworm-Type Bimetallic Sulfide (NiMo3S4) Nanostructures Developed on S-g-C3N4 Sheets: Promising Electrode Material for Supercapacitors

“…Recently, with the availability of various types of electrode materials for SCs, ternary transition metal sulfides (TMS) are becoming promising new electrode materials due to their superior conductivity and high electrochemical activity compared with widely studied metal oxide materials. − Despite its attractive electrochemical properties, bare TMS alone is prone to face low specific capacitance. To overcome this issue, a new strategy is encouraged to be proposed to enhance the specific capacity of TMS electrode materials. , As of now, the practical specific capacity of TMS is very small compared with theoretical values due to high charge transfer resistance and lower utility of active material. Among TMS materials, spinel-type NiCo 2 S 4 is extensively investigated for SCs due to its high theoretical capacitance, abundant availability, low economic, and ease of synthesis .…”

“…Among TMS materials, spinel-type NiCo 2 S 4 is extensively investigated for SCs due to its high theoretical capacitance, abundant availability, low economic, and ease of synthesis . Alternatively, there are mere reports on hierarchical NiMo 3 S 4 batteries and SCs . However, these bimetallic sulfides alone as an electrode material are prone to low cycling stability.…”

“…However, these bimetallic sulfides alone as an electrode material are prone to low cycling stability. Hence, investigations on bimetallic TMS-based composites are in progress to achieve better electrochemical performance. , Recent research investigations suggest that the appropriate selection and design of TMS with various types of composites can enhance the specific capacitance due to the synergistic effect of various mechanisms, which can further improve the redox reactions. ,− …”

In Situ Growth of Core–Shell Heterostructure CePO4@CuCo2S4 As Advanced Electrodes for High-Performance Supercapacitor

“…20 Due to the synergistic effect of its unique 3D heterostructure, it provides excellent rate performance and ultrahigh capacity with values of 599.9 C g −1 at 1 A g −1 , respectively. Huang fabricated an extraordinary 3D hierarchical NiMoS 4 @CuCo 2 S 4 grass-like structure 21 with a specific capacity of 13.14 F cm −2 at 5 mA cm −2 and splendid rate performance due to its unique morphology. Na et al synthesized CuCo 2 S 4 @NiCo(OH) 2 nanoparticles 2 with a specific capacitance of 2340 F g −1 as a new core−shell hybrid material when the lowest current density was 1 A g −1 .…”