Construction of Nickel Molybdenum Sulfide/Black Phosphorous 3D Hierarchical Structure Toward High Performance Supercapacitor Electrodes

Abstract

Supercapacitors (SCs) with outstanding versatility have a lot of potential applications in next-generation electronics. However, their practical uses are limited by their short working potential window and ultralow-specific capacity. Herein, the facile one-step in-situ hydrothermal synthesis is employed for the construction of a NiMo₃S₄/BP (black phosphorous) hybrid with a 3D hierarchical structure. After optimization, the NiMo₃S₄/BP hybrid displays a high specific capacitance of 830 F/g at 1 A/g compared to the pristine NiMo₃S₄ electrode. The fabricated NiMo₃S₄/BP//NiCo₂S₄/Ti₃C₂Tx asymmetric supercapacitor exhibits a better specific capacitance of 120 F/g at 0.5 A/g, which also demonstrates a high energy density of 54 Wh/kg at 1148.53 W/kg and good cycle stability with capacity retention of 86% and 97% of Coulombic efficiency after 6000 cycles. Further from the DFT simulations, the hybrid NiMo₃S₄/BP structure shows higher conductivity and quantum capacitance, which demonstrate greater charge storage capability, due to enhanced electronic states near the Fermi level. The lower diffusion energy barrier for the electrolyte K₊ ions in the hybrid structure is facilitated by improved charge transfer performance for the hybrid NiMo₃S₄/BP. This work highlights the potential significance of hybrid nanoarchitectonics and compositional tunability as an emerging method for improving the charge storage capabilities of active electrodes.