Nanoparticle-Mediated Physical Exfoliation of Aqueous-Phase Graphene for Fabrication of Three-Dimensionally Structured Hybrid Electrodes

Abstract

Monodispersed polypyrrole (PPy) nanospheres were physically incorporated as guest species into stacked graphene layers without significant property degradation, thereby facilitating the formation of unique three-dimensional hybrid nanoarchitecture. The electrochemical properties of the graphene/particulate PPy (GPPy) nanohybrids were dependent on the sizes and contents of the PPy nanospheres. The nanohybrids exhibited optimum electrochemical performance in terms of redox activity, charge-transfer resistance, and specific capacitance at an 8:1 PPy/graphite (graphene precursor) weight ratio. The packing density of the alternately stacked nanohybrid structure varied with the nanosphere content, indicating the potential for high volumetric capacitance. The nanohybrids also exhibited good long-term cycling stability because of a structural synergy effect. Finally, fabricated nanohybrid-based flexible all–solid state capacitor cells exhibited good electrochemical performance in an acidic electrolyte with a maximum energy density of 8.4 Wh kg−1 or 1.9 Wh L−1 at a maximum power density of 3.2 kW kg−1 or 0.7 kW L−1; these performances were based on the mass or packing density of the electrode materials.

A Solution-Processable, Nanostructured, and Conductive Graphene/Polyaniline Hybrid Coating for Metal-Corrosion Protection and Monitoring

“…Under induced electrochemical polarization, the protection efficiency of the GPn coating was 17.0% and 20.9% larger than that of pure PANI in 1 M H 2 SO 4 and 3.5 wt% NaCl solutions, respectively. The GPn can be easily produced using an efficient top-down approach and is adaptable to solution processing 33 , 34 . Therefore, we believe that commercialization of our material will be possible in the near future.…”

Fire-Safe Polymer Composites: Flame-Retardant Effect of Nanofillers

“…This is because they have a high thermal stability, strong barrier effect, and large specific surface adsorption capability, which are favorable for reducing heat and mass transfer [ 101 , 184 ]. Many studies have proven that graphene and its derivatives can have significant effects on the pyrolysis of polymers [ 36 , 98 , 99 , 185 ], as well as on their thermal conductivity, heat absorption, and dripping [ 184 , 185 , 186 , 187 ]. This suggests that they could be powerful flame retardants because they can ameliorate the polymer thermal stability and delay its ignition; furthermore, they can inhibit the fire from spreading and reduce the HRR [ 188 ].…”

Recent Advances in Nanostructured Conducting Polymers: from Synthesis to Practical Applications

“…Typically, graphene/CP nanohybrid electrodes can be used to fabricate high-performance, flexible, solid-state electrochemical capacitors. Very recently, PPy nanospheres were intercalated into stacked graphene layers, which resulted in a unique 3D opened structure that allowed facile electrolyte diffusion [147]. As a result, the nanohybrids had high capacitance, as well as good long-term cycling stability.…”

“…Exfoliation of graphite by CPs may be an efficient strategy for functionalization of graphene with CPs [147]. This method is more beneficial than the conventional approach due to the high electrical conductivity of pure graphene layers.…”