Bendable solid-state supercapacitors with au nanoparticle-embedded graphene hydrogel films _ scientific reports


In recent years, bendable electrical double layer capacitors—or supercapacitors—have been regarded as one of the most promising energy storage devices, owing to their fast charge/discharge rates and favorable cycle lifetimes when compared with batteries 1, 2, 3, 4. Exchange rate usd jpy Unlike batteries, which store energy through electrochemical reactions in the electrode bulk, supercapacitors store energy primarily at the interface of the electrode and electrolyte. Eur usd historical data download High-performance supercapacitors are therefore evaluated by whether or not electrode materials are sufficiently conductive to transport charge carriers to the electrolyte interface. Pre market dow jones futures To date, research on supercapacitor electrodes has been concentrated on the development of materials with high specific surface areas, rather than on materials with sufficient electrical conductivity 5, 6, 7. Usd rate of exchange Graphene hydrogel (GH) has recently been in the spotlight as a promising electrode material for supercapacitors, owing to its 3D porous network, which leads to a high specific surface area 8, 9, 10. Binary code translator However, it has a downside in that the agglomeration of graphene sheets in GH results in a decrease of electrical conductivity and an increase of internal resistance.

Malaysian ringgit to usd The graphene agglomeration is an undesirable but inevitable by-product obtained during electrode fabrication. Gender quiz lgbt The internal resistance comprehends the electrolyte resistance, the resistance of the electrode active-material, and the contact resistance between the active materials and the current collector 11, 12, and is responsible for an ohmic (IR) drop—potential drop—that has adverse effects on the supercapacitor’s power density, high-rate capability, and applicability scope. Used book stores Therefore, to fabricate supercapacitors without an IR drop, it is imperative to enhance the electrical conductivity of the GH electrodes and to reduce the contact resistance between the electrodes and the current collectors 13. Binary number translator Therefore, in this study, we attempt to reduce the internal resistance by embedding Au nanoparticles (NPs) into the GH electrodes. Cnn futures markets Furthermore, we examine the characteristics of the resulting supercapacitors under tensile and compressive stresses, to confirm the possibility of their use as bendable energy storage devices.

Based on the above-described results, we propose a conceptual model for the voltage distribution profile of an SC in the fully charged state; the model can be seen in Fig. Video editor linux mint 6, where C 1 and C 2 designate the double layer electrical capacitances, and R ct and R s indicate the charge transfer resistance and series resistance, respectively, as per Fig. Usd to aud exchange rate 4. Html to word converter An instantaneous voltage drop, known as IR drop, occurs when the SC switches from charging to discharging, as a result of the combined ohmic resistance of the electrodes, electrolyte, and contact resistances in the system. Machine learning artificial intelligence The total usable voltage window (ΔV) is therefore reduced by the IR drop. Rm to usd Both the contact resistance between the current collector and the electrode and the resistance of the electrode itself are relatively lower in the NP-GH SC, because of the conductive Au NPs. Usd to inr today As a consequence, the ΔV of the NP-GH SC is larger than that of the GH SC, as can be seen on the voltage distribution profiles.