Graphene nanosheets were produced in large quantity via a soft chemistry synthetic route involving graphite oxidation, ultrasonic exfoliation, and chemical reduction. X-ray diffraction and transmission electron microscopy (TEM) observations show that graphene nanosheets were produced with sizes in the range of tens to hundreds of square nanometers and ripple-like corrugations. High resolution TEM (HRTEM) and selected area electron diffraction (SAED) analysis confirmed the ordered graphite crystal structure of graphene nanosheets. The optical properties of graphene nanosheets were characterized by Raman spectroscopy.

Highly ordered mesoporous MoS2 with a high surface area and narrow pore‐size distribution is synthesized by a vacuum assisted impregnation route. The mesoporous MoS2 demonstrates an expanded d002 spacing of 0.66 nm. The mesoporous MoS2 electrode achieves an excellent high rate capacity of 608 mAh g−1 at the discharge current of 10 A g−1 (∼15C), which places MoS2 as a viable next generation high power source for electric vehicles.

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Rational design and controllable synthesis of TiO2 based materials with unique microstructure, high reactivity, and excellent electrochemical performance for lithium ion batteries are crucially desired. In this paper, we developed a versatile route to synthesize hollow TiO2/graphitic carbon (H-TiO2/GC) spheres with superior electrochemical performance. The as-prepared mesoporous H-TiO2/GC hollow spheres present a high specific surface area (298 m(2) g(-1)), a high pore volume (0.31 cm(3) g(-1)), a large pore size (∼5 nm), well-defined hollow structure (monodispersed size of 600 nm and inner diameter of ∼400 nm, shell thickness of 100 nm), and small nanocrystals of anatase TiO2 (∼8 nm) conformably encapsulated in ultrathin graphitic carbon layers. As a result, the H-TiO2/GC hollow spheres achieve excellent electrochemical reactivity and stability as an anode material for lithium ion batteries. A high specific capacity of 137 mAh g(-1) can be achieved up to 1000 cycles at a current density of 1 A g(-1) (5 C). We believe that the mesoporous H-TiO2/GC hollow spheres are expected to be applied as a high-performance electrode material for next generation lithium ion batteries.

In this work, we have synthesized highly ordered mesoporous NiO materials by a nanocasting method using mesoporous silica KIT-6 as the hard templates. Mesoporous NiO particles were characterized by small angle X-ray diffraction (XRD), nitrogen adsorption/desorption, and transmission electron microscopy (TEM). The results demonstrated that the as-prepared mesoporous NiO had an ordered Ia3d symmetric mesostructure, with a high surface area of 96 m 2 /g. Mesoporous NiO materials were tested as an anode material for lithium ion batteries, exhibiting much lower activation energy (20.75 kJ mol À1 ) compared to the bulk NiO (45.02 kJ mol À1 ). We found that the mesoporous NiO electrode has higher lithium intercalation kinetics than its bulk counterpart. The specific capacity of mesoporous NiO after 50 cycles was maintained 680 mAh/g at 0.1 C, which was much higher than that of the commercial bulk NiO (188 mAh/g). Furthermore, at a high rate of 2C, the discharge capacity of mesoporous NiO was as high as 515 mAh/g, demonstrating the potential to be used for high power lithium ion batteries.