3D Graphene–Cobalt Oxide Electrode for High-Performance Supercapacitor and Enzymeless Glucose Detection

Abstract

Using a simple hydrothermal procedure, cobalt oxide (Co(3)O(4)) nanowires were in situ synthesized on three-dimensional (3D) graphene foam grown by chemical vapor deposition. The structure and morphology of the resulting 3D graphene/Co(3)O(4) composites were characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, and Raman spectroscopy. The 3D graphene/Co(3)O(4) composite was used as the monolithic free-standing electrode for supercapacitor application and for enzymeless electrochemical detection of glucose. We demonstrate that it is capable of delivering high specific capacitance of ∼1100 F g(-1) at a current density of 10 A g(-1) with excellent cycling stability, and it can detect glucose with a ultrahigh sensitivity of 3.39 mA mM(-1) cm(-2) and a remarkable lower detection limit of <25 nM (S/N = 8.5).

Silver nanoparticles decorated on a three-dimensional graphene scaffold for electrochemical applications

“…To the best of our knowledge, only a few pioneering studies on 3D graphene-metal composites have been done [23,[25][26][27][28]. In this study, we report on the enhanced electrochemical performance of CVD-grown graphene foam (GF) decorated with silver nanoparticles using a physical technique (electron beam evaporation).…”

Two-dimensional NiCo2O4nanosheet-coated three-dimensional graphene networks for high-rate, long-cycle-life supercapacitors

“…Although high-capacitance pseudocapacitors have been achieved using pseudocapacitive materials as electrodes, they normally suffer from low power density and unstable cycling performance because of their intrinsically low electrical conductivity. [20][21][22] Due to their high porosity, large internal surface area, and outstanding electrical and mechanical properties, 23,24 three-dimensional graphene networks (3DGNs) serve as a striking platform for construction of composite electrodes with enhanced properties for wide applications, such as supercapacitors, 20,[24][25][26][27][28] Li-ion batteries, [29][30][31][32] catalysis, [33][34][35] and sensors. 26,36 Particularly, supercapacitors constructed from 3DGN based-materials have been studied to achieve enhanced electrochemical performances including higher specific capacitance, better rate capability and longer cycle life.…”

Preparation and Electrochemical Characterization of La Doping Co3O4 Super Capacitor Electrode Materials

“…With the Co 3 O 4 sample experimentally obtained as a positive electrode, polytetrafluoroethylene (PTFE) as a binder and acetylene black as a conductive agent, the electrode materials to construct working electrodes were composed of active materials (Co 3 O 4 , 80 wt%, 1 mg/cm -2 ), conductive material (acetylene carbon black, ATB, 10 wt%) and binder (polytetrafluoroethylene, PTFE, 10 wt%).After the mixture of electrode materials was ground, International Conference on Chemical, Material and Food Engineering (CMFE-2015) it was coated onto the surfaces of nickel foam meshes(1×3 cm 2 ) and pressed with a hammer. sheets with electrode materials were dried for experiment.…”

“…Cobalt oxide is a transition metal oxide spinel, playing an important role in engineering technology, with excellent electrochemical properties, catalytic properties and magnetic properties [1][2][3][4][5][6]. There are hydrothermal method [2,[7][8][9], the thermal decomposition method [10][11], solid-phase precipitation [12], sol-gel method [3,[13][14] and chemical vapor deposition method [15][16] for preparing Co 3 O 4 in laboratory.…”

“…There are hydrothermal method [2,[7][8][9], the thermal decomposition method [10][11], solid-phase precipitation [12], sol-gel method [3,[13][14] and chemical vapor deposition method [15][16] for preparing Co 3 O 4 in laboratory. Generally using the thermal decomposition of cobalt salts to get Co 3 O 4 is easy to operate in industry.…”