Ni–Co Selenide Nanosheet/3D Graphene/Nickel Foam Binder-Free Electrode for High-Performance Supercapacitor

Abstract

Transition-metal selenide electrodes have recently attracted increasing interest in supercapacitors resulting from their superior electrochemical performance, lower-cost, and environmental friendliness. Herein, we report a novel bimetallic Ni−Co selenide nanosheet/three-dimensional (3D) graphene/nickel foam binder-free electrode (NiCo 2.1 Se 3.3 NSs/3D G/NF) prepared via chemical vapor deposition followed by a simple two-step hydrothermal process in this paper. The NiCo 2.1 Se 3.3 NSs array vertically on 3D G/NF with a uniform and stable structure without using any chemical binders. This novel electrode is flexible, highly conductive, and exhibits an excellent specific capacitance of ∼742.4 F g −1 at 1 mA cm −2 . Furthermore, with a 10-fold increase to 10 mA cm −2 , it still retains 471.78 F g −1 and a high cycling stability of ∼83.8% of the initial retention after 1000 cycles at 10 mA cm −2 , demonstrating that NiCo 2.1 Se 3.3 NSs/3D G/NF binder-free electrode has potential for energy storage application in highperformance supercapacitor fields. KEYWORDS: bimetallic Ni−Co selenide nanosheets (NiCo 2.1 Se 3.3 NSs), three-dimensional graphene/nickel foam (3D G/NF), binder-free electrode, high performance, supercapacitor applications

Heterostructured Nickel‐Cobalt Selenide Immobilized onto Porous Carbon Frameworks as an Advanced Anode Material for Urea Electrocatalysis

“…In addition, the Se 3d core‐level of Se region (Figure D) exhibits two peaks at 54.6 eV and 55.4 eV attributed to Se 3d 5/2 and Se 3d 3/2 , respectively. The peaks observed at 59.4 eV is ascribed to the existence of oxidized Se …”

A facile method to synthesize CoV2O6 as a high-performance supercapacitor cathode

“…This small change demonstrates that the electrode material has an excellent electrochemical performance. 33 Note that materials with better cycling stability are more promising in commercial applications. Therefore, CoV 2 O 6 was tested via 20 000 cycles of continuous charge and discharge at the current density of 4 A g À1 .…”

Recent Progress in Two‐Dimensional Layered Double Hydroxides and Their Derivatives for Supercapacitors

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