Controllable synthesis and morphology engineering of S-doped NiCo layered double hydroxide nanoflowers for high-performance supercapacitors

The poor electrical conductivity and pronounced structural instability of NiCo Layered Double Hydroxide are of major challenge in energy storage. Herein, three distinct morphological types of S doped nickel cobalt layered double hydroxides, S-LDH-x/NF (x = Ⅰ, Ⅱ and Ⅲ) electrodes are successfully prepared from thiol-functionalized conductive metal organic frameworks NiCo-MOF-x/NF (x = Ⅰ, Ⅱ, Ⅲ) precursors through the synergistic method of in situ interfacial synthesis via coordinated growth and etching. Among them, S-LDH-Ⅱ/NF with nanoflower morphology shows excellent electrochemical performances with high conductivity and remarkable cycling stability, and the surface capacitance is 2617 mF/cm 2 (1 mA/cm 2 ). What's more, the S-LDH-Ⅱ//AC ASC affords a density of energy of 99 Wh/kg (0.182 mWh/cm 2 ) at 415 W/kg (0.76 mW/cm 2 ). In addition, after 10,000 cycling cycles, the S-LDH-Ⅱ//AC ASC still maintains 74 % capacitance retention, indicating its exceptional cycling performance. This paper offers a new approach for designing novel energy storage materials based on thiol-functionalized bimetallic conductive metal organic framework templates through synergistic synthesis method and morphology engineering strategy.