Hierarchical Nickel–Cobalt Phosphide/Phosphate/Carbon Nanosheets for High-Performance Supercapacitors

Abstract

Transition-metal phosphates/phosphides, as an emerging kind of prominent electroactive material, have drawn extensive attention in the fields of energy conversion and storage owing to their high electrical conductivity and metal-like properties. Herein, we report the preparation of hierarchical Ni–Co–P/PO x /C nanosheets in a controllable manner using nickel–cobalt metal–organic framework (NiCo-MOF) as the precursor, followed by a low-temperature phosphating method. Electrochemical studies show that the Ni–Co–P/PO x /C nanosheets exhibit good reversible capacity and excellent rate capability and possess capacities of 583 and 365.7 C g–1 at 1 and 30 A g–1, respectively. Furthermore, a two-electrode device assembled by Ni–Co–P/PO x /C and reduced graphene oxide shows a peak energy density of 37.59 Wh kg–1 at a power density of 800 W kg–1 and a stable capacitive performance. These results indicate that the obtained bimetallic Ni–Co–P/C is a promising anode material for capacitive energy storage devices.

Synthesis and Study on Ni-Co Phosphite/Activated Carbon Fabric Composited Materials with Controllable Nano-Structure for Hybrid Super-Capacitor Applications

“…The Ragone plot of the MHP/ACF@ACF hybrid device and some results from other works are listed in Figure 9 c. The MHP/ACF@ACF hybrid device recorded the highest energy density, of 34.1 Wh·kg −1 , and a power density of 722 W·kg −1 at 1 A·g −1 , which is similar or superior to those reported results [ 13 , 38 , 39 , 40 , 41 , 42 , 43 ].…”

A multi-interface CoNi-SP/C heterostructure for quasi-solid-state hybrid supercapacitors with a graphene oxide-containing hydrogel electrolyte

“…It should be mentioned that the organic ligands in CoNi-MOF can be converted into the carbon matrix around transition metal compounds under an inert atmosphere as certified below. 39 This suggests the multi-phase structure of CoNi-SP/C, which contains NiCoP, Co 9 S 8 , Ni 9 S 8 , and carbon.…”

“…47,53,57 In addition, the MOF-derived carbon matrix within CoNi-SP/C enables delivery of enhanced performance in energy storage compared to MOF materials. 39…”

Metal–organic framework‐derived phosphide nanomaterials for electrochemical applications

“…What's more, dual electrode equipment brought together by Ni-Co-P/PO x /C and decreased oxide of graphene exhibited the highest energy concentration of 37.59 Wh kg −1 at an energy concentration of 800 W kg −1 and a steady capacitive behavior, indicating that the prepared bimetallic Ni-Co-P/C is hopeful for being used as an anode material in capacitive energy storage devices. 220 Also, as Zhou argued, because of the coexistence and synergism of various transition metals, binary metal compounds possess richer redox reactions and higher conductivity. Moreover, carbon, when used for composite materials, possesses the benefits of promoting electronic conductivity to enhance fast electron transmissions.…”