Hollow Bimetallic Phosphosulfide NiCo–P/S Nanoparticles in a CNT/rGO Framework with Interface Charge Redistribution for Battery-Type Supercapacitors

Abstract

As remarkable pseudocapacitive materials with rich faradic redox reactions, Ni–Co bimetallic compounds have gained much research interest as high-performance battery-type supercapacitor electrodes. Herein, we report a strategy that can enhance the energy storage capability of supercapacitors by constructing bimetallic phosphosulfides via simultaneous phosphorization and sulfuration processes. Compared to a single phosphide, the bimetallic phosphosulfide of NiCo–P/S presented a highly porous and hollow nanoparticle structure, which renders more active electrochemical reactions. It is demonstrated that the coexistence of phosphide and sulfide phases can regulate charge distribution to improve electronic transportation capability. Besides, it is also proved that the precalcination of the NiCo-LDH precusor into NiCo oxides is necessary to achieve adequate phosphorization or sulfuration. By anchoring NiCo–P/S hollow nanoparticles into a CNT/rGO hybrid network, superior capacitive performances were demonstrated, presenting remarkable capacity (698.6 C g–1 at 1 A g–1) as well as promising rate performance (a capacity retention ratio of 61.5% at 20 A g–1) as an electrode material for supercapacitors. An asymmetric supercapacitor device employing a NiCo–P/S@C@G composite was also fabricated. The device presented favorable energy density at high power density and was able to power a light-emitting diode (LED) for several minutes, proving outstanding practical properties of the composite.

Tuned Bimetallic Fe–Ni Thiophosphides as Advanced Battery Materials for Asymmetric Electrochemical Supercapacitors with Outstanding Energy Density

“…This heterostructure showed a specific capacity of 75.8 C/g at 0.2 A/g and delivered an energy density of 29.01 Wh/kg. Moreover, NiCoPS@CNT@rGo was synthesized via a multiple-step process . First, Co-MOF (ZIF-67) was loaded onto carbon nanotubes (CNTs), and then Ni and reduced graphene oxide were added by a solvothermal method into ZIF-67.…”

“…Moreover, NiCoPS@CNT@rGo was synthesized via a multiple-step process. 24 First, Co-MOF (ZIF-67) was loaded onto carbon nanotubes (CNTs), and then Ni and reduced graphene oxide were added by a solvothermal method into ZIF-67. This was followed by the conversion of Ni−Co layered double hydroxide into Ni−Co oxides and then sulfurization and phosphorization to obtain Ni−Co phosphosulfide.…”

Investigation of the mechanical and transport properties of InGeX3 (X = S, Se and Te) monolayers using density functional theory and machine learning

“…, in which F i and L j are the stress and transverse lattice constant, respectively. 53 The stress-strain relations of InGeX 3 (X = S, Se and Te) monolayers are investigated using ground state DFT at 0 K and the results are shown in Fig. 4.…”

In Situ Transformation of Metal Molybdates into Polymetallic Sulfides with Enriched Edge Sites for High-Performance Supercapacitors

“…Supercapacitors, a new class of energy storage devices, have caused widespread concern due to their high power density, fast charge−discharge capability, long cycling life, and environmental friendliness. 1 Currently, bimetal oxides, including cobaltite (MCo 2 O 4 , M = Mn, Ni, and Zn) and molybdates (MMoO 4 , M = Co and Ni), are regarded as promising electrode materials for supercapacitors due to their multiple oxidation states, excellent electrical conductivity, and high surface area for redox reactions. 2 Especially, metal molybdates, MMoO 4 (M: Ni, Co, Mn, etc.…”