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Partikel und Blätter: Polyanilin dient als Brücke zur Kupplung von Metalloxiden und ‐ hydroxiden mit Graphenschichten. Eine Hydrothermalbehandlung überführt die gekuppelten Hybride in N ‐ dotierte Kohlenstoffnanoblätter, in denen Metallpartikel kontrollierter Größe eingeschlossen sind. Ihre Struktur verleiht diesen 2D ‐ Nanohybriden vielversprechende elektrochemische Eigenschaften in Superkondensatoren und in der Sauerstoffreduktion. [ABSTRACT FROM AUTHOR]

The article discusses a study which proposes a synthetic approach in the production of two-dimensional (2D) conjugated microporous polymers based on graphene. It mentions the methods used for the synthesis of the conjugate that involved the reduction of a graphene oxide sheet (GO) with hydrazine hydrate (RGO), dispersion of bromo-functionalized RGO, and scanning electron microscopy (SEM). It adds that the synthesis method is expected to provide the opportunity to create 2D porous polymers.

A composite of perylene diimide/reduced graphene oxide (PDI/RGO) is fabricated via a hit-and-run strategy in this work. In the hitting step, the ionic self-assembly of positively charged N,N′-bis(N-ethyl-N,N-dimethylhexan-1-aminium)perylene-3,4,9,10-tetracarboxylic diimide bromide (N + -PDI) and negative charged graphene oxide (GO) leads to the formation of the highly wrinkled composites (N + -PDI/RGOs) in solution. In the following running step to generate PDI/RGO, the composite of N + -PDI and solvothermally reduced GO is thermally treated at 300 °C to remove the ammonium groups in N + -PDI and further improve the conductivity. As the cathode in sodium ion battery (SIB), PDI/RGO delivers a specific capacity of ∼175 mA h g −1 at 50 mA g −1 even after 500 charge-discharge cycles and still maintains a capacity of ∼73 mA h g −1 at 800 mA g −1 , outperforming most of the state-of-art organic SIB cathodes. More importantly, the investigation on the changes of the composites during the fabrication processes enables the understanding of the influences of the morphology, crystallinity, and compositions on their electrochemical performances in SIB, which will be helpful for the design of high performance organic electrodes in secondary batteries. [ABSTRACT FROM AUTHOR]

In this work, leaf-like hybrid with Bi 2 O 2 CO 3 nanotubes as the “veins” and graphene sheet as the “laminae” is fabricated via a facile one-pot reaction of bismuth nitrate and graphene oxide in alkaline aqueous solution. With the uniform distribution of Bi 2 O 2 CO 3 nanotubes on the graphene substrate, the obtained Bi 2 O 2 CO 3 -NT/G manifests high specific surface area (90.4 m 2 g −1 ) and large pore volume (0.197 cm 3 g −1 ), which are favorable for the efficient light capturing together with the rapid transfer of mass and charge carriers. In comparison with the pure Bi 2 O 2 CO 3 nanotubes and commercial Bi 2 O 2 CO 3 , Bi 2 O 2 CO 3 -NT/G exhibits much enhanced activity and long-term stability towards the photocatalytic degradation of organic dye pollutant, which is owing to its unique leaf-like structural features. [ABSTRACT FROM AUTHOR]

A novel lyotropic liquid-crystal (LC) based assembly strategy is developed for the first time, to fabricate composite films of vanadium pentoxide (V2O5) nanobelts and graphene oxide (GO) sheets, with highly oriented layered structures. It is found that similar lamellar LC phases can be simply established by V2O5 nanobelts alone or by a mixture of V2O5 nanobelts and GO nanosheets in their aqueous dispersions. More importantly, the LC phases can be retained with any proportion of V2O5 nanobelts and GO, which allows facile optimization of the ratio of each component in the resulting films. Named VrGO, composite films manifest high electrical conductivity, good mechanical stability, and excellent flexibility, which allow them to be utilized as high performance electrodes in flexible energy storage devices. As demonstrated in this work, the VrGO films containing 67 wt% V2O5 exhibit excellent capacitance of 166 F g−1 at 10 A g−1; superior to those of the previously reported composites of V2O5 and nanocarbon. Moreover, the VrGO film in flexible lithium ion batteries delivers a high capacity of 215 mAh g−1 at 0.1 A g−1; comparable to the best V2O5 based cathode materials. [ABSTRACT FROM AUTHOR]

Herein, we present an electrochemically assisted method for the reduction of graphene oxide (GO) and the assembly of polyoxometalate clusters on the reduced GO (rGO) nanosheets for the preparation of nanocomposites. In this method, the Keggin-type H4SiW12O40 (SiW12) is used as an electrocatalyst. During the reduction process, SiW12 transfers the electrons from the electrode to GO, leading to a deep reduction of GO in which the content of oxygen-containing groups is decreased to around 5 %. Meanwhile, the strong adsorption effect between the SiW12 clusters and rGO nanosheets induces the spontaneous assembly of SiW12 on rGO in a uniformly dispersed state, forming a porous, powder-type nanocomposite. More importantly, the nanocomposite shows an enhanced capacity of 275 mAh g−1 as a cathode active material for lithium storage, which is 1.7 times that of the pure SiW12. This enhancement is attributed to the synergistic effect of the conductive rGO support and the well-dispersed state of the SiW12 clusters, which facilitate the electron transfer and lithium-ion diffusion, respectively. Considering the facile, mild, and environmentally benign features of this method, it is reasonable as a general route for the incorporation of more types of functional polyoxometalates onto graphene matrices; this may allow the creation of nanocomposites for versatile applications, for example, in the fields of catalysis, electronics, and energy storage. [ABSTRACT FROM AUTHOR]