Freon-CO-assisted purification of single-walled carbon nanotubes.

With the rapidly growing applications, efficient purification of single-walled carbon nanotubes (SWCNTs) has become one of the key problems. This paper proposes Freon-CO-assisted purification of SWCNTs, where CO can oxidize the graphitized carbon layer to expose iron (Fe) impurities, while the chlorine from Freon can react with the Fe impurities to form low-boiling-point metal chlorides that can be eliminated in a gas stream. After an acid washing with a very small amount of hydrochloric acid, the last remaining metal impurities are removed and highly pure SWCNTs are produced.

Flexible All-Carbon Nanoarchitecture Built from In Situ Formation of Nanoporous Graphene Within "Skeletal-Capillary" Carbon Nanotube Networks for Supercapacitors.

It is difficult for carbonaceous materials to combine a large specific surface area with flexibility. Here, a flexible all-carbon nanoarchitecture based on the in situ growth of nanoporous graphene within "skeletal-capillary" carbon nanotube (CNT) networks has been achieved by a chemical vapor deposition (CVD) process. Multi-path long-range conductivity is established, and the porous graphene provides a large specific surface area for charge storage.

Stable dispersion of carbon nanotubes in a molten salt of KNO-NaNO-NaNO-LiNO-LiOH.

Carbon nanotubes (CNTs) have excellent mechanical and electrical properties; however, they suffer from dispersion problems in various applications. Traditional dispersing strategies of CNTs mostly use oxidation with strong acids or mechanical milling with high energy, which causes serious damage to the intrinsic structures and properties of CNTs. Therefore, it is important to develop new methods for dispersing CNTs without destroying their structures.

Unraveling the Fundamental Mechanism of Interface Conductive Network Influence on the Fast-Charging Performance of SiO-Based Anode for Lithium-Ion Batteries.

Influence of interface conductive network on ionic transport and mechanical stability under fast charging is explored for the first time. The mitigation of interface polarization is precisely revealed by the combination of 2D modeling simulation and Cryo-TEM observation, which can be attributed to a higher fraction formation of conductive inorganic species in bilayer SEI, and primarily contributes to a linear decrease in ionic diffusion energy barrier. The improved stress dissipation presented by AFM and Raman shift is critical for the linear reduction in electrode residual stress and thickness swelling.

Conversion of coal into N-doped porous carbon for high-performance SO adsorption.

The large-scale burning of coal has led to increasingly serious SO environmental pollution problems. The SO adsorption and removal technology based on porous carbons has the advantages of less water consumption, no secondary pollution, recycling of pollutants, and renewable utilization of adsorbents, in contrast to the wet desulfurization process. In this work, we developed a series of N-doped coal-based porous carbons (NCPCs) by calcining a mixture of anthracite, MgO, KOH and carbamide at 800 °C.

Self-Supported Porous Ni-Fe-W Hydroxide Nanosheets on Carbon Fiber: A Highly Efficient Electrode for Oxygen Evolution Reaction.

Structural and compositional modulation of low-cost hydroxide is important for making efficient electrocatalysts of the oxygen evolution reaction (OER), and it is an ongoing challenge. Here, Ni-Fe-W hydroxide complex by incorporation of tungsten into nickel-iron layered double hydroxide was proposed and investigated. As-formed Ni-Fe-W hydroxide nanosheets are highly porous and self-supported on the carbon fiber substrates, which promote the exposure of the active metal sites for significantly enhanced OER activity.

Capacitive Sodium-Ion Storage Based on Double-Layered Mesoporous Graphene with High Capacity and Charging/Discharging Rate.

Sodium-ion batteries (SIBs) are regarded as an ideal alternative to lithium-ion batteries, but the larger radius of Na compared with Li results in lower energy density, shorter cycle life, and sluggish kinetics of SIBs. Therefore, it is of significant importance to explore appropriate Na storage materials with high capacity and fast Na transport kinetics. Herein, doublelayered mesoporous graphene nanosheets codoped with oxygen and nitrogen (O,N-MGNSs) were developed as a new cathode material with high Na storage capacity and fast ion-transport kinetics for SIBs.

Tuning Microstructures of Graphene to Improve Power Capability of Rechargeable Hybrid Aqueous Batteries.

Low conductivity and structural degradation of LiMnO lead to poor power capability and severe capacity fading of hybrid aqueous Zn/LiMnO battery. Here, we propose an effective strategy by tuning the microstructures of graphene to optimize its electrical and interfacial properties and electrode dynamics of LiMnO/graphene cathodes, which successfully prompt significant improvements in electrical conductivity and structural stability, thus essentially leading to a promising electrochemical performance. More importantly, it reveals different electrochemical properties prompted by different conductivity, which mainly depends on the microstructures of graphene.

Advances in Production and Applications of Carbon Nanotubes.

Recent decades have witnessed many breakthroughs in research on carbon nanotubes (CNTs), particularly regarding controllable synthesis, production scale-up, and application advances for this material. This sp -bonded nanocarbon uniquely combines extreme mechanical strength, exceptionally high electrical conductivity, as well as many other superior properties, making it highly attractive for fundamental research and industrial applications. Synthesis and mass production form the solid basis for high-volume applications of CNTs.

Aerosol-Assisted Heteroassembly of Oxide Nanocrystals and Carbon Nanotubes into 3D Mesoporous Composites for High-Rate Electrochemical Energy Storage.

Nanostructured composites built from ordinary building units have attracted much attention because of their collective properties for critical applications. Herein, we have demonstrated the heteroassembly of carbon nanotubes and oxide nanocrystals using an aerosol spray method to prepare nanostructured mesoporous composites for electrochemical energy storage. The designed composite architectures show high conductivity and hierarchically structured mesopores, which achieve rapid electron and ion transport in electrodes.

Building robust carbon nanotube-interweaved-nanocrystal architecture for high-performance anode materials.

Rational design of electrode materials is essential but still a challenge for lithium-ion batteries. Herein, we report the design and fabrication of a class of nanocomposite architecture featured by hierarchically structured composite particles that are built from iron oxide nanocrystals and carbon nanotubes. An aerosol spray drying process was used to synthesize this architecture.

A novel method to enhance the conductance of transitional metal oxide electrodes.

Transitional metal oxides hold great potential for high capacity anodes. However, the low electron conductivity of such materials leads to poor cycling stability and inferior rate capability. We reported herein the use of a novel hydrogen plasma technology to improve the conductance of metal oxides, which leads great success in improving the rate performance of CuO nanotube based anodes.

Building robust architectures of carbon and metal oxide nanocrystals toward high-performance anodes for lithium-ion batteries.

Design and fabrication of effective electrode structure is essential but is still a challenge for current lithium-ion battery technology. Herein we report the design and fabrication of a class of high-performance robust nanocomposites based on iron oxide spheres and carbon nanotubes (CNTs). An efficient aerosol spray process combined with vacuum filtration was used to synthesize such composite architecture, where oxide nanocrystals were assembled into a continuous carbon skeleton and entangled in porous CNT networks.

High-performance sodium-ion pseudocapacitors based on hierarchically porous nanowire composites.

Electrical energy storage plays an increasingly important role in modern society. Current energy storage methods are highly dependent on lithium-ion energy storage devices, and the expanded use of these technologies is likely to affect existing lithium reserves. The abundance of sodium makes Na-ion-based devices very attractive as an alternative, sustainable energy storage system.

High-performance energy-storage architectures from carbon nanotubes and nanocrystal building blocks.

High-performance energy-storage architectures are fabricated by forming conformal coatings of active nanocrystal building blocks on preformed carbon nanotube conductive scaffolds for lithium ion electrodes. This unique structure offers effective pathways for charge transport, high active-material loading, structure robustness, and flexibility. This general approach enables the fabrication of a new family of high-performance architectures for energy storage and many other applications.

Direct growth of flexible LiMn2O4/CNT lithium-ion cathodes.

Flexible, binder-free LiMn(2)O(4)/CNT nanocomposites with good reversible capability and cycling stability were fabricated by in-situ hydrothermal growth for flexible lithium battery applications.