Self-assembled PANI/CeO2/Ni(OH)2 hierarchical hybrid spheres with improved energy storage capacity for high-performance supercapacitors

Nitrogen-Doped Cellulose-Derived Porous Carbon Fibers for High Mass-Loading Aqueous Supercapacitors

Biomass-based porous carbon with renewability and flexible structure tunability is a promising electrode material for supercapacitors. However, there is a huge gap between experimental research and practical applications. How to maintain good electrochemical performance of high mass-loading electrodes and suppress the self-discharge of supercapacitors is a key issue that urgently needs to be addressed. The structure regulation of electrode materials such as heteroatom doping is a promising optimization strategy for high mass-loading electrodes. In this work, nitrogen-doped cellulose-derived porous carbon fibers (N-CHPCs) were prepared by a facile bio-template method using cotton cellulose as raw material and urea as dopant. The prepared N-CHPCs have high specific surface area, excellent hierarchical porous structure, partial graphitization properties and suitable heteroatom content. The assembled high mass-loading (12.8 mg cm-2 ; 245 μm) aqueous supercapacitor has excellent electrochemical performance, i. e., low open-circuit voltage attenuation rate (21.39 mV h-1 ), high voltage retention rate (78.81 %), high specific capacitance (295.8 F g-1 at 0.1 A g-1 ), excellent area capacitance (3.79 F cm-2 at 0.1 A g-1 ), excellent cycling stability (97.28 % over 20,000 cycles at 1.0 A g-1 ). The excellent performance of high mass-loading N-CHPCs is of great significance for their practical applications in advanced aqueous supercapacitors.

Rare Earth-Based Nanomaterials for Supercapacitors: Preparation, Structure Engineering and Application

Supercapacitors (SCs) can effectively alleviate problems such as energy shortage and serious greenhouse effect. The properties of electrode materials directly affect the performance of SCs. Rare earth (RE) is known as "modern industrial vitamins", and their functional materials have been listed as key strategic materials. In the past few years, the number of scientific reports on RE-based nanomaterials for SCs has increased rapidly, confirming that adding RE elements or compounds to the host electrode materials with various nanostructured morphologies can greatly enhance their electrochemical performance. Although RE-based nanomaterials have made rapid progress in SCs, there are very few works providing a comprehensive survey of this field. In view of this, a comprehensive overview of RE-based nanomaterials for SCs is provided here, including the preparation methods, nanostructure engineering, compounds, and composites, along with their capacitance performances. The structure-activity relationships are discussed and highlighted. Meanwhile, the future challenges and perspectives are also pointed out. This Review can not only provide guidance for the further development of SCs but also arouse great interest in RE-based nanomaterials in other research fields such as electrocatalysis, photovoltaic cells, and lithium batteries.

Two-in-one template-assisted construction of hollow phosphide nanotubes for electrochemical energy storage

In this work, the template-assisted method was used to develop novel Ni2P@PANI hollow nanotubes as a positive electrode material for supercapacitors by using prepared polyaniline (PANI) nanotubes as precursors, and...