Binder-Free Phosphorus-Modified Multiphase Ni-Co Sulfide Nanoarchitectures with Sea-Urchin Morphology for...

Owing to the high demand for advanced energy storage, the exceptional characteristics of transition metal sulfides have attracted great interest from researchers. Herein, phosphorus (P)-encapsulated nickel-cobalt sulfides (NCSs) prepared via a hydrothermal process and phosphorized in a tube furnace to produce P@NCS₂₀ (with 20 mM sulfur source) are reported. The P@NCS₂₀ material is synthesized through a meticulous multistep process, ensuring precise control of its material properties. Successful incorporation of P significantly enhances the electrochemical performance of the electrode. The electrochemical evaluation demonstrates the superior performance of the P@NCS₂₀ electrode. Cyclic voltammetry and galvanostatic charge-discharge curves reveal enhanced oxidation/reduction behavior and high areal capacity. Electrochemical testing shows high redox reactions and decreased electrode-electrolyte resistance, and the P@NCS₂₀ electrode can last for over 10000 cycles. A hybrid supercapacitor (HSC) constructed with P@NCS₂₀ and activated carbon/nickel foam electrodes exhibits a specific capacitance of 95.93 F g^-1 at 3 mA cm^-2. This HSC device demonstrates outstanding cycling stability, and it can efficiently store solar energy and continuously power electronic devices. This work emphasizes the potential of P@NCS₂₀ electrode materials in advanced energy storage systems and provides a systematic and simple synthesis procedure with important implications for sustainable energy applications.