Facile Sulfuration Route to Enhance the Supercapacitor Performance of 3D Petal‐like NiV‐Layered Double Hydroxide

The charge conductivity properties and ionic delivery of pseudocapacitive materials are important factors for the charge storage process. Herein, the new petal-like S-NiV-layered double hydroxide (LDH) materials are successfully synthesized by a presynthetic solvothermal reaction and a sulfidation modification procedure. The specific capacitance of the new petal-like S-NiV-LDHs electrode reaches 1403 F g−1 when the current density is 1 A g−1, and this is attributed to Ni3S2 formed on the surface of NiV-LDHs. When the current density is up to 20 A g−1, the rate performance of the new petal-like S-NiV-LDHs electrode is 65.04%. It can be seen that the comprehensive electrochemical performance of the new petal-like S-NiV-LDHs is better than the petal-like NiV-LDHs before modification. When the power density of the S-NiV-LDHs//activated carbon asymmetric supercapacitor cell is 2278.48 W kg−1, its energy density is 20 Wh kg−1. The innovation of this work lies in that, based on the microstructure of petal-like NiV-LDHs with rich mesoporous structure, the surface of petal-like NiV-LDHs is slightly sulfurized, which makes the new petal-like S-NiV-LDHs electrode material have smaller electrochemical impedance, richer oxidation states, richer chemical active sites, better energy storage, and cycle stability.