All-Solid-State Reduced Graphene Oxide Supercapacitor with Large Volumetric Capacitance and Ultralong Stability Prepared by Electrophoretic Deposition Method

Abstract

Portable energy storage devices have gained special attention due to the growing demand for portable electronics. Herein, an all-solid-state supercapacitor is successfully fabricated based on a poly(vinyl alcohol)-H3PO4 (PVA-H3PO4) polymer electrolyte and a reduced graphene oxide (RGO) membrane electrode prepared by electrophoretic deposition (EPD). The RGO electrode fabricated by EPD contains an in-plane layer-by-layer alignment and a moderate porosity that accommodate the electrolyte ions. The all-solid-state RGO supercapacitor is thoroughly tested to give high specific volumetric capacitance (108 F cm(-3)) and excellent energy and power densities (7.5 Wh cm(-3) and 2.9 W cm(-3), respectively). In addition, the all-solid-state RGO supercapacitor exhibits an ultralong lifetime for as long as 180 days (335 000 cycles), which is an ultrahigh cycling capability for a solid-state supercapacitor. The RGO is also tested for being used as a transparent supercapacitor electrode demonstrating its possible use in various transparent optoelectronic devices. Due to the facile scale-up capability of the EPD process and RGO dispersion, the developed all-solid-state supercapacitor is highly applicable to large-area portable energy storage devices.

A highly conductive porous graphene electrode prepared via in situ reduction of graphene oxide using Cu nanoparticles for the fabrication of high performance supercapacitors

“…6A), suggesting a typical electric double layer capacitance and good charge transport within the RGO electrodes. [63][64][65] The specific capacitance of the as-fabricated capacitor was calculated to be 165 F g -1 and 121 F g -1 at the scan rate of 5 mV s -1 and 200 mV s -1 respectively, indicating an excellent capacitance performance and low contact resistance in the capacitors. Fig.…”

Electrophoretic deposition of graphene-related materials: A review of the fundamentals

“…For example, electrodes for electrochemical double layer supercapacitors rely on high structural porosity as well as a large interlayer separation of GRM sheets to allow effective electrolyte access and to maximise the active surface area for charge storage [15,63,96,124,143]. On the other hand, field emission of electrons at low voltages requires a high surface roughness and a predominance of well distributed, individualised GRM edges [39,85,91,92,101,[144][145][146].…”

Facile hydrothermal synthesis of hexapod-like two dimensional dichalcogenide NiSe2 for supercapacitor

“…The electrochemical performance of the supercapacitor is mainly reliant on the electrode material which triggers the research community to develop new electrodes with high energy density, power density and cycle life. Till date, such efforts have been achieved through novel two dimensional (2D) layered materials including graphene, reduced graphene oxides and chalcogenides [2][3][4][5]. In particular, 2D transition metal dichalcogenides (TMD) such as NiS 2 , CoS 2 , MoS 2 , VS 2 , WS 2 and MoSe 2 have been proved as high performance supercapacitor electrode materials [6][7][8][9][10][11].…”