Liqiang Mai,*,† Xiaocong Tian,† Xu Xu,† Liang Chang,‡ and Lin Xu†,§ †State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, WUT-Harvard Joint Nano Key Laboratory, Wuhan University of Technology, Wuhan 430070, China ‡Department of Materials Science and Engineering, Michigan Technological University, Houghton, Michigan 49931-1295, United States Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, United States

Nanowire electrodes for electrochemical energy storage devices.

Electrochemical energy storage technology is of critical importance for portable electronics, transportation and large-scale energy storage systems. There is a growing demand for energy storage devices with high energy and high power densities, long-term stability, safety and low cost. To achieve these requirements, novel design structures and high performance electrode materials are needed. Porous 1D nanomaterials which combine the advantages of 1D nanoarchitectures and porous structures have had a significant impact in the field of electrochemical energy storage. This review presents an overview of porous 1D nanostructure research, from the synthesis by bottom-up and top-down approaches with rational and controllable structures, to several important electrochemical energy storage applications including lithium-ion batteries, sodium-ion batteries, lithium-sulfur batteries, lithium-oxygen batteries and supercapacitors. Highlights of porous 1D nanostructures are described throughout the review and directions for future research in the field are discussed at the end.

Porous One-Dimensional Nanomaterials: Design, Fabrication and Applications in Electrochemical Energy Storage.

In this paper, the hierarchical SnO2 nanostructures (HTNs) were prepared by a facile hydrothermal process. The prepared HTNs were characterized in detail by various analytical techniques that reveal the well-crystallinity with tetragonal rutile structure of SnO2 for the as-prepared material. By detailed experiments, interestingly, it was observed that the shapes and sizes of as-prepared HTNs could be tailored by varying the precursor concentration and reaction time. The synthesized HTNs were used as the efficient photocatalysts for the photocatalytic degradation of methylene blue (MB) under light illumination which showed almost complete degradation (∼99%) of MB dye in 20 min. The observed degradation for MB dye was higher than other commonly used dyes, i.e. methyl orange (MO; 96% in 50 min) and Rhodamine B (RhB; 97% in 40 min.). Further, the prepared HTNs were used as the effective gas sensing material to examine a series of volatile gases, such as ethanol, ammonia, benzene, acetone, toluene, methanol, d...

Hierarchical SnO2 Nanostructures Made of Intermingled Ultrathin Nanosheets for Environmental Remediation, Smart Gas Sensor, and Supercapacitor Applications

MoSe2 nanosheets perpendicularly grown on graphene with Mo–C bonding for sodium-ion capacitors

Nanomaterials provide many desirable properties for electrochemical energy storage devices due to their nanoscale size effect, which could be significantly different from bulk or micron-sized materials. Particularly, confined dimensions play important roles in determining the properties of nanomaterials, such as the kinetics of ion diffusion, the magnitude of strain/stress, and the utilization of active materials. Nanowires, as one of the representative one-dimensional nanomaterials, have great capability for realizing a variety of applications in the fields of energy storage since they could maintain electron transport along the long axis and have a confinement effect across the diameter. In this review, we give a systematic overview of the state-of-the-art research progress on nanowires for electrochemical energy storage, from rational design and synthesis, in situ structural characterizations, to several important applications in energy storage including lithium-ion batteries, lithium-sulfur batteries, sodium-ion batteries, and supercapacitors. The problems and limitations in electrochemical energy storage and the advantages in utilizing nanowires to address the issues and improve the device performance are pointed out. At the end, we also discuss the challenges and demonstrate the prospective for the future development of advanced nanowire-based energy storage devices.

Nanowires for Electrochemical Energy Storage.

In this work, we report the synthesis of porous SnO2 nanowire bundles with high yield through a simple solution approach. The bundles are composed of porous SnO2 nanowires with overall diameters in the range of 80–120 nm. Growth control of the sample morphology is demonstrated by adjusting the dose of Sn precursor. Functional tests of the nanowire bundles include photocatalytic effect in the degradation of Rhodamine B (RhB), and electrochemical properties as a Li-ion battery anode. The electrochemical test reveals that the as-synthesized product shows a very high reversible capacity and Coulombic efficiency in the initial cycles, as well as reasonably good cycling performance compared with other SnO2 nanostructures. Such porous SnO2 nanostructures synthesized by the simple and cheap method are expected to have application potential in waste water treatment and/or energy storage.

Porous SnO2 nanowire bundles for photocatalyst and Li ion battery applications

Solution Growth and Cathodoluminescence of Novel SnO2Core−Shell Homogeneous Microspheres

Large-scale novel core−shell microspheres of SnO2 have been synthesized through a simple solution method at 200 °C. Morphologies, microstructures, and compositions of the products are investigated by X-ray powder diffraction, Raman spectroscopy, scanning electron microscopy, and transmission electron microscopy. Results indicate that the SnO2 microspheres are core−shell structures with an average diameter of 6 μm and an average shell thickness of 200 nm. A growth mechanism and the cathodoluminescence properties of these novel structures are presented.

Solution Growth and Cathodoluminescence of Novel SnO2 Core-Shell Homogeneous Microspheres

The invention discloses a method for synthesizing a porous SnO2 nano-wire harness, relates to a preparation method for a nano-wire harness, and mainly solves the problems of complex process, high organic raw material cost, expensive equipment and industrial production limitation caused by high reaction temperature in the conventional preparation method. The method for synthesizing the porous SnO2nano-wire harness comprises the following steps of: firstly, uniformly mixing absolute ethanol and polyethylene glycol 600; secondly, adding SnCl2.2H2O into the mixed solution; thirdly, centrifuging to obtain precipitate; fourthly, performing centrifugal washing on the precipitate with deionized water; fifthly, performing centrifugal washing on the precipitate with the absolute ethanol; and finally, drying and annealing to obtain the porous SnO2 nano-wire harness. The method has mild reaction conditions, can perform reaction at a normal temperature and normal pressure without heating, has lowrequirement on reaction equipment, saves energy source and does not generate harmful substances in a reaction process. The method has a simple process, easily obtained raw materials, low cost, environment friendliness, and broad application prospect in a semiconductor material field, and is safe and convenient to operate.

Yutao Han

Papers

Porous SnO2 nanowire bundles for photocatalyst and Li ion battery applications

Solution Growth and Cathodoluminescence of Novel SnO2Core−Shell Homogeneous Microspheres

Solution Growth and Cathodoluminescence of Novel SnO2 Core-Shell Homogeneous Microspheres

Method for synthesizing porous SnO2 nano-wire harness