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.

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It is highly desirable but challenging to develop bifunctional catalysts for efficiently catalyzing both oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) in energy storage and conversion system. Here a simple yet cost-effective strategy is developed to fabricate nitrogen and phosphorus dual-doped graphene/carbon nanosheets (N,P-GCNS) with N,P-doped carbon sandwiching few-layer-thick graphene. The as-prepared N,P-GCNS shows outstanding catalytic activity towards both ORR and OER with a potential gap of 0.71 V between the OER potential at a current density of 10 mA cm -2 and the ORR potential at a current density of -3 mA cm -2 , illustrating that it is the best metal-free bifunctional electrocatalysts reported to date. The superb bifunctional catalytic performance is attributed to the synergistic effects between the doped N and P atoms, the full exposure of the active sites on the surface of the N,P-GCNS nanosheets, the high conductivity of the incorporated graphene, the large surface area and hierarchical pores for sufficient contact and rapid transportation of the reactants.

Metal-free phosphorus-doped graphene nanosheets (P-TRG) with large surface area (496.67 m 2 g 21 ) and relatively high P-doping level (1.16 at.%) were successfully prepared by thermal annealing a homogenous mixture of graphene oxide and 1-butyl-3-methlyimidazolium hexafluorophosphate under argon atmosphere. It was found that the P atoms were substitutionally incorporated into the carbon framework and were partially oxidized, which created new active sites for the oxygen reduction reaction (ORR).Accordingly, the ORR catalytic performance of the P-doped graphene was demonstrated to be better than or at least comparable to that of the benchmark Pt/C catalyst.

In the Communication by D. Li et al., the wrong journal was cited in reference [3c], the correct reference is included below. We apologize for this oversight.[3] c) C.

Here we report on the synthesis of a graphene/polyaniline (PANI) nanocomposite and its application in the development of a hydrogen (H2) gas sensor. Using a chemical synthetic route, graphene was prepared and ultrasonicated with a mixture of aniline monomer and ammonium persulfate to form PANI on its surface. The developed material was characterized by scanning electron microscopy (SEM), transmission electron microscopy, Raman spectroscopy, and X-ray photoemission spectroscopy. The SEM study revealed that the PANI in the composite has a nanofibrillar morphology. We investigated the H2 gas sensing performance of this material and compare it with that of the sensors based on only graphene sheets and PANI nanofibers. We found that the graphene/PANI nanocomposite-based device sensitivity is 16.57% toward 1% of H2 gas, which is much larger than the sensitivities of sensors based on only graphene sheets and PANI nanofibers.

We demonstrated in this paper the shape-controlled synthesis of ZnIn2S4, CuInS2, and CuInSe2 nano- and microstructures through a facile solution-based route. One-dimensional ZnIn2S4 nanotubes and nanoribbons were synthesized by a solvothermal method with pyridine as the solvent, while ZnIn2S4 solid or hollow microspheres were hydrothermally prepared in the presence of a surfactant such as cetyltrimethylammonium bromide (CTAB) or poly(ethylene glycol) (PEG). The mechanisms related to the phase formation and morphology control of ZnIn2S4 are proposed and discussed. The UV-vis absorption spectra show that the as-prepared nano- and micromaterials have strong absorption in a wide range from UV to visible light and that their band gaps are somewhat relevant to the size and morphology. The photoluminescence measurements of the ZnIn2S4 microspheres at room temperature reveal intense excitation at approximately 575 nm and red emission at approximately 784 nm. Furthermore, CuInS2 and CuInSe2 with different morphologies such as spheres, platelets, rods, and fishbone-like shapes were also obtained by similar hydrothermal and solvothermal synthesis.

High‐power alkaline Zn–MnO2 batteries with superior discharge performance have been constructed using γ‐MnO2 nanowires/nanotubes (see Figure) and electrolytic zinc powder as the cathode and anode active materials, respectively. The improvement in discharge performance over commercial batteries is believed to be derived from the lower inner resistance of the batteries and the high utilization efficiency of the active materials.