Hierarchical porous reduced graphene oxide decorated with molybdenum disulfide for high-performance supercapacitors

Fabrication of ternary composites with polymeric carbon nitride/MoS2/reduced graphene oxide ternary hybrid aerogel as high-performance electrode materials for supercapacitors

Presenting a remarkable ternary hybrid aerogel, as an excellent electrode material with a specific capacitance of 467 Fg−1 and capacitance retention upto 80.4% even after 2000 cycles, demonstrating good stability and improved cyclic performance.

Recent Advances of Two-Dimensional Nanomaterials for Electrochemical Capacitors

Two-dimensional (2D) nanomaterials have drawn a wide range of research interests because of their unique ultrathin layered structures and attractive properties. In particular, the electrochemical properties and great variety of 2D nanomaterials make them highly attractive candidates for electrochemical capacitors, such as supercapacitors, lithium-ion capacitors, and sodium-ion capacitors. Herein, a comprehensive review of recent progress towards the application of 2D nanomaterials for electrochemical capacitors is provided. Several typical types of 2D nanomaterials are first briefly introduced, followed by detailed descriptions of their electrochemical capacitor applications. Finally, research perspectives and future research directions of these interesting areas are also provided.

Application of MoS2 in the cathode of lithium sulfur batteries

Molybdenum disulfide (MoS₂) with a two-dimensional layered structure can effectively inhibit the shuttle effect of lithium–sulfur batteries (Li–S batteries). It contains metal–sulfur bonds and combines with polysulfides through electrostatic bonds or chemical bonds. In this paper, the structure and properties of MoS₂ are briefly introduced, and the research progress on the design, preparation, structure and properties of MoS₂ as a cathode material for Li–S batteries in recent years is reviewed. The effects of MoS₂ structure and its composition with carbon materials or metallic oxides on the performance of the electrode materials are analyzed. Finally, the existing problems and possible future research directions are pointed out.

Molybdenum disulfide (MoS₂) with a two-dimensional layered structure can effectively inhibit the shuttle effect of lithium–sulfur batteries (Li–S batteries).

Recent Advances of Porous Graphene: Synthesis, Functionalization, and Electrochemical Applications

Graphene is a 2D sheet of sp² bonded carbon atoms and tends to aggregate together, due to the strong π-π stacking and van der Waals attraction between different layers. Its unique properties such as a high specific surface area and a fast mass transport rate are severely blocked. To address these issues, various kinds of 2D holey graphene and 3D porous graphene are either self-assembled from graphene layers or fabricated using graphene related materials such as graphene oxide and reduced graphene oxide. Porous graphene not only possesses unique pore structures, but also introduces abundant exposed edges and accelerates mass transfer. The properties and applications of these porous graphenes and their composites/hybrids have been extensively studied in recent years. Herein, recent progress and achievements in synthesis and functionalization of various 2D holey graphene and 3D porous graphene are reviewed. Of special interest, electrochemical applications of porous graphene and its hybrids in the fields of electrochemical sensing, electrocatalysis, and electrochemical energy storage, are highlighted. As the closing remarks, the challenges and opportunities for the future research of porous graphene and its composites are discussed and outlined.

Hierarchical TiO2-x nanoarchitectures on Ti foils as binder-free anodes for hybrid Li-ion capacitors

Hybrid Li-ion capacitor (LIC) draws more attention as novel energy storage device owing to its high power density and high energy density. Designing three-dimensional electrode materials is beneficial for improving electrochemical performance of LICs. Herein, an improved hydrothermal method combined with an ion-exchange reaction is used to manufacture oxygen vacancies (OVs)-doping TiO₂ (TiO_2-x) nanowires/nanosheets (NWS) on Ti-foil. Then TiCl₄ treatment is performed to form TiO_2-x NWS/nanocrystallines (NWSC). These-obtained hierarchical nanoarchitectures assumes enrich electro-active sites and contact areas, which can improve electron transference and structural stability. The TiO_2-x NWSC is used as binder-free anode for Li-ion battery and achieves high specific capacity (300 mAh g^-1 at 0.1 A g^-1), excellent rate capability (102 mAh g^-1 at 5 A g^-1) and long cycle stability (44% after 1000 cycles at 1 A g^-1). LICs assembled with a TiO_2-x NWSC anode and an activated carbon cathode have an energy density of 44.2 W h kg^-1 at the power density of 150 W kg^-1. Therefore, the TiO_2-x NWSC is a potential candidate for high energy and high power electrochemical energy storage devices.