部分硫化法制备镍锰氢氧化物-二硫化镍电极材料及其储能性能

Nickel and manganese, as two transition metals, were selected to synthesize three-dimensional flower-like bimetallic metal-organic framework (NiMn-MOF) which was stacked by two dimensional nanosheets by solvothermal method. Using NiMn-MOF as precursor, the mesoporous NiMn-layered double hydroxide (LDH)-NiS₂ composite electrode materials (NiMn-LDH-S) were prepared based on alkali etching and in situ partial vulcanization. The effects of the amount of sulfur source on the morphology, structure and electrochemistry of in-situ vulcanization products were systematically studied. The results show that the maximum specific capacitance of NiMn-LDH-S is 1 783 F·g⁻¹ (0.5 A·g⁻¹) when the addition of thioacetamide is 8 mmol, and the initial capacitance of NiMn-LDH-S could be maintained by 57.90% after 3 000 cycles at 10 A·g⁻¹. The NiMn-LDH-S//active carbon (AC) hybrid supercapacitor (HSC) assembled with the synthetic NiMn-LDH-S composites as the positive electrode, active carbon as the negative electrode and 2 mol·L⁻¹ KOH as the electrolyte has a high energy density of 27.11 W·h·kg⁻¹ at 800 W·kg⁻¹. The energy storage device is capable of powering 2.0− 2.2 V commercial LED lights (red, yellow and green) and keeping them on for 20 min.