Recent Development of Polyaniline/graphene Composite Electrodes for Flexible Supercapacitor Devices

With the fast development of portable and wearable devices, flexible supercapacitor electrodes are widely researched. Here, comprehensive approaches were designed to introduce carbon nanotube (CNT) and/or MnO2 into activated carbon fiber felt (ACFF) using “dipping and drying” method. Differences on micro-morphologies and electrochemical characteristics for prepared textiles were compared. High-performance flexible MnO2/CNT/ACFF composite electrodes were synthesized by introducing CNT and MnO2/CNT fillers successively. Compared with original ACFF textiles, significant improvements in electrochemical performance were achieved. Areal capacitance, energy density and power density of the composite textiles reached as high as 4148 mF cm−2, 141 μWh cm−2 and 4466 μW cm−2, respectively. Furthermore, flexible supercapacitors were fabricated based on the composite textile electrodes and gel electrolytes. When being bent at different angles or suffering deformations such as bending for 100 cycles, the flexible supercapacitors preserve almost all the capacitance, which indicates the excellent flexibility of the composite textile electrode. This work provides various approaches to design composite textiles, and the prepared MnO2/CNT/ACFF composite textile may be a promising electrode material for high-performance flexible supercapacitors.

PEDOT counterions enabled oriented polyaniline nanorods for high performance flexible supercapacitors

To prevent and mitigate environmental degradation, high-performance and cost-effective electrochemical flexible energy storage systems need to be urgently developed. This demand has led to an increase in research on electrode materials for high-capacity flexible supercapacitors and secondary batteries, which have greatly aided the development of contemporary digital communications and electric vehicles. The use of layered double hydroxides (LDHs) as electrode materials has shown productive results over the last decade, owing to their easy production, versatile composition, low cost, and excellent physicochemical features. This review highlights the distinctive 2D sheet-like structures and electrochemical characteristics of LDH materials, as well as current developments in their fabrication strategies for expanding the application scope of LDHs as electrode materials for flexible supercapacitors and alkali metal (Li, Na, K) ion batteries.

NaTi2(PO4)3/C‖carbon package asymmetric flexible supercapacitors with the positive material recycled from spent Zn‒Mn dry batteries

Bicontinuous nanotubular graphene–polypyrrole hybrid for high performance flexible supercapacitors

Reduced graphene oxide/polymer dots-based flexible symmetric supercapacitors delivering an output potential of 1.7 V with electrochemical charge injection

Conductive polymer electrode materials with excellent mechanical and electrochemical properties for flexible supercapacitor

Chapter 6 - Oxides free materials for flexible and paper-based supercapacitors

Construction of extensible and flexible supercapacitors from covalent organic framework composite membrane electrode

Advances in MXene-based composites for next-generation flexible supercapacitors: From design and development to applications.

Highly conductive and flexible porous carbon nanofibers cloth for high-performance supercapacitor

Three-dimensional hierarchical core-shell CuCo2O4@Co(OH)2 nanoflakes as high-performance electrode materials for flexible supercapacitors

Flexible supercapacitors are gaining a lot of attention in the field of wearable, portable and flexible electronic devices. The flexible supercapacitors provide high power density and are lightweight in nature. Graphene-based materials have proved great potential as flexible supercapacitor electrode materials owning to its excellent supercapacitive properties. In this chapter, the current progress in fabrication techniques and supercapacitive performance of graphene oxide–based flexible supercapacitors is illustrated. Furthermore, a brief discussion on future directions regarding challenges in this area is also explored.

Flexible supercapacitors are of great significance for the development of intelligent electronic products and wearable devices. Herein, through reasonable design, self-supporting flexible film composites that can be used as supercapacitor electrodes, are synthesised by vacuum filtration. The composites are composed of electrochemically exfoliated graphene nanosheets and MnO2 nanowires, in which the graphene nanosheets mainly play the role of skeleton support, enhance conductivity, and provide electric double-layer capacitance, while the MnO2 nanowires mainly provide pseudocapacitance. Results show that the sample with 20 % MnO2 possesses the best electrochemical performance due to the mass ratio which can give full play to the pseudocapacitive properties of MnO2 and the conductivity of graphene. The maximum mass specific capacitance reaches 106.2 F g−1 at 0.5 A g−1, and the areal specific capacitance is 767.0 mF cm−2 at 1 mA cm−2. The electrode also maintains 86.7 % of the initial capacitance after 10000 cycles, indicating good cyclic stability. Furthermore, an asymmetric solid supercapacitor based on flexible thin films is assembled. The energy density is 20.7 W h kg−1, the power density is 1000 W kg−1, and the capacitance remains 84.2 % after 3000 cycles at 5.0 A g−1. These results suggest that the as-prepared self-supporting material has the potential to be used to construct flexible supercapacitors for wearable equipment.

Fabrication of stretchable multi-element composite for flexible solid-state electrochemical capacitor application