Graphene-based 3D composite hydrogel by anchoring Co3O4 nanoparticles with enhanced electrochemical properties

Abstract

Three-dimensional (3D) graphene-based composite materials have attracted increasing attention, owing to their specific surface area, high conductivity and electronic interactions. Here, we report a convenient route to fabricate a 3D Co3O4/Graphene Hydrogel (CGH) composite as an electrode material for supercapacitors. Utilizing the gelation of a graphene oxide dispersion enables the anchoring of Co3O4 nanoparticles on the graphene sheet surfaces and formation of the hydrogel simultaneously. Remarkably, the spherical Co3O4 particles can serve as spacers to keep the neighboring graphene sheets separated. The CGH exhibits a high specific capacitance (Cs) of 757.5 F g(-1) at a current density of 0.5 A g(-1), indicating its potential application as an electrode material for supercapacitors.

Self‐Assembled 3D Graphene‐Based Aerogel with Co3O4 Nanoparticles as High‐Performance Asymmetric Supercapacitor Electrode

“…In the Raman spectrum of the RGO aerogel and the Co 3 O 4 -RGOa erogel (Figure 2b) www.chemsuschem.org residual adsorption peaks around 1620 cm À1 can be assigned to the stretchingv ibration of the originalc arbon backbone (d C=C ). [40] These resultsi llustrate that GO is almost reduced by thermalr eduction. Moreover,t he 3D Co 3 O 4 -RGO aerogel shows strong absorptions at 668 and 578 cm À1 due to decompositiono ft he hydroxide to Co 3 O 4 .F urthere vidence for the formationo ft he Co 3 O 4 -RGO composite was obtained from XPS analysis( Figure S1, SupportingI nformation).…”

One-step preparation of single-crystalline Fe2O3 particles/graphene composite hydrogels as high performance anode materials for supercapacitors

“…However, their specific capacitances (128-226 F g À 1 ) are fundamentally limited by the electrical double layer mechanism [35][36][37][38][39][40][41]. To enhance energy densities, recent works have shown supercapacitor application of graphene hydrogels combined with some pseudocapacitive cathode materials such as Co 3 O 4 [42], Ni(OH) 2 [43] and MnCO 3 [44]. Besides, graphene/VO 2 composite hydrogels have been reported to exhibit a specific capacitance of 426 F g À 1 at 1 A g À 1 in the potential range of À0.6 to 0.6 V, which is indicative of a positive synergistic effect of VO 2 and graphene on the improvement of electrochemical performance [45].…”

MoS2 nanosheets decorated with ultrafine Co3O4 nanoparticles for high-performance electrochemical capacitors

“…However, the high surface energy and possible weak ferromagnetism of nanoscale Co 3 O 4 may cause serious particle aggregation. To prevent such phenomenon and improve electrical conductivity, researchers have extensively investigated novel Co 3 O 4 -based composite structures for hybrid supercapacitor applications [9][10][11][12].…”