One-step cathodic electrodeposition of a cobalt hydroxide–graphene nanocomposite and its use as a high performance supercapacitor electrode material

Abstract

In this study, Co(OH) 2 -reduced graphene oxide has been synthesized using a simple and rapid one-step cathodic electrodeposition method in a two electrode system at a constant current density on a stainless steel plate, and then characterized as a supercapacitive material on Ni foam. The composites were characterized by FT-IR, X-ray diffraction, scanning electron microscopy, and cyclic voltammetry using a galvanostatic charge/discharge test.The feeding ratios of the initial components for electrodeposition had a significant effect on the structure and electrochemical performance of the Co(OH) 2 -reduced graphene oxide composite. The results show that the 1 : 4 (w/w) ratio of GO : CoCl 2 $6H 2 O was optimum and produced an intertwined composite structure with impressive supercapacitive behavior. The specific capacitance of the composite was measured to be 734 F g À1 at a current density of 1 A g À1. Its rate capability was $78% at 20 A g À1 and its capacitance retention was 95% after 1000 cycles of charge-discharge. Moreover, its average energy density and power density were calculated to be 60.6 W h kg À1 and 3208 W kg À1, respectively. This green synthesis method enables a rapid and low-cost route for the large scale production of Co(OH) 2 -reduced graphene oxide nanocomposite as an efficient supercapacitor material.

Electrodeposition of Binder-Free Peptide/Co(OH)2Nanohybrid Electrodes for Solid-State Symmetric Supercapacitors

“…Warburg resistance, which appears owing to OH – ion diffusion and transport in the electrolyte, is attributed to the straight line at the post-semicircle in the low-frequency area. The BSeYY/Co­(OH) 2 /CP nanohybrid electrode shows vertical lines at the lower frequency region corresponding to ideal capacitive behaviors. − The GCD cycling performance (Figure d) of the BSeYY/Co­(OH) 2 /CP hybrid electrode is obtained with 78.62% capacitance retention after 3000 cycles at 18 A g –1 in 1 M KOH electrolyte solution. Figure a represents the comparative CV analysis of the BSeYY/Co­(OH) 2 /CP hybrid electrode and bare CP electrode in 1 M KOH and 1 M LiOH electrolytes.…”

“…The BSeYY/Co­(OH) 2 /CP hybrid electrode exhibits higher electrochemical performance as compared to the recently developed cobalt hydroxide and organic–inorganic hybrid-based electrodes. The electrochemical activity of cobalt-based nanomaterials and hybrids has been compared with BSeYY/Co­(OH) 2 nanohybrids in Table S2. ,,,− …”

Hybrid nanostructured bismuth‐cobalt oxides/hydroxides binder‐free electrodes fabricated by two‐step electrodeposition for high‐performance supercapacitors

“…This method has strong controlling parameters, such as the active ion concentration, pH, applied potential, and deposition time. Electrodeposition can produce size variations that directly affect electrochemical performance 26 . In binder‐free electrodes, the dead volume caused by an insulating binder agent can be solved 27 .…”

“…Electrodeposition can produce size variations that directly affect electrochemical performance. 26 In binder-free electrodes, the dead volume caused by an insulating binder agent can be solved. 27 However, during electron transfer, ion diffusion, and Faradaic reactions, the active thin films on the electrode can be removed from the electrolyte, leading to unstable performance for a long duration.…”

Iridium Oxide Nanoparticle–Protein Corona Neural Interfaces with Enhanced Electroactivity and Bioactivity Enable Electrically Manipulatable Physical and Chemical Neuronal Activation

“…Electrochemical deposition is a useful strategy for the integration of heterogeneous nanomaterials in aqueous solutions with enhanced bonding interactions and controllable atomic structural arrangements. [ 19 ] The redox current allows the efficient control of the nucleation and growth of inorganic NPs, thereby enhancing the atomic scale interfacial bonding interactions with the incorporated materials to form a stable hybrid complex. [ 20,21 ] Polymers can be immobilized in situ on as‐grown inorganic NPs present in the electrolyte by cyclic voltammetry (CV).…”