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Particles and sheets: Polyaniline is used as a linker to couple metal oxides and hydroxides to graphene sheets. Hydrothermal treatment converts these coupled hybrids into nitrogen‐doped 2D carbon nanosheets integrated with size‐controlled metal nanoparticles. This structure gives these 2D nanohybrids promising electrochemical behavior in supercapacitors and oxygen‐reduction reactions. [ABSTRACT FROM AUTHOR]

Review: 130 refs. [ABSTRACT FROM AUTHOR]

Heteroatom doping is an effective method to adjust the electrochemical behavior of carbonaceous materials. In this work, boron-doped, carbon-coated SnO2/graphene hybrids (BCTGs) were fabricated by hydrothermal carbonization of sucrose in the presence of SnO2/graphene nanosheets and phenylboronic acid or boric acid as dopant source and subsequent thermal treatment. Owing to their unique 2D core-shell architecture and B-doped carbon shells, BCTGs have enhanced conductivity and extra active sites for lithium storage. With phenylboronic acid as B source, the resulting hybrid shows outstanding electrochemical performance as the anode in lithium-ion batteries with a highly stable capacity of 1165 mA h g−1 at 0.1 A g−1 after 360 cycles and an excellent rate capability of 600 mA h g−1 at 3.2 A g−1, and thus outperforms most of the previously reported SnO2-based anode materials. [ABSTRACT FROM AUTHOR]

The article discusses the novel graphene-inspired synthesis of two-dimensional (2D) sandwichlike, graphene-based conjugated microporous polymers (GMPs). It says that nuclear magnetic resonance (NMR) spectroscopy was conducted to study the molecular structure of GMP-S. It states that the exciton dynamic of MP-S and GMP-S was examined by time-resolved photoluminescence spectroscopy. It mentions that the 2D porous polymers were used in preparing heteroatom-doped 2D porous carbons.

Abstract: Structurally well‐defined graphene nanoribbons (GNRs) have attracted great interest because of their unique optical, electronic, and magnetic properties. However, strong π–π interactions within GNRs result in poor liquid‐phase dispersibility, which impedes further investigation of these materials in numerous research areas, including supramolecular self‐assembly. Structurally defined GNRs were synthesized by a bottom‐up strategy, involving grafting of hydrophilic poly(ethylene oxide) (PEO) chains of different lengths (GNR‐PEO). PEO grafting of 42–51 % percent produces GNR‐PEO materials with excellent dispersibility in water with high GNR concentrations of up to 0.5 mg mL−1. The “rod–coil” brush‐like architecture of GNR‐PEO resulted in 1D hierarchical self‐assembly behavior in the aqueous phase, leading to the formation of ultralong nanobelts, or spring‐like helices, with tunable mean diameters and pitches. In aqueous dispersions the superstructures absorbed in the near‐infrared range, which enabled highly efficient conversion of photon energy into thermal energy. [ABSTRACT FROM AUTHOR]

Abstract: Structurally well‐defined graphene nanoribbons (GNRs) have attracted great interest because of their unique optical, electronic, and magnetic properties. However, strong π–π interactions within GNRs result in poor liquid‐phase dispersibility, which impedes further investigation of these materials in numerous research areas, including supramolecular self‐assembly. Structurally defined GNRs were synthesized by a bottom‐up strategy, involving grafting of hydrophilic poly(ethylene oxide) (PEO) chains of different lengths (GNR‐PEO). PEO grafting of 42–51 % percent produces GNR‐PEO materials with excellent dispersibility in water with high GNR concentrations of up to 0.5 mg mL−1. The “rod–coil” brush‐like architecture of GNR‐PEO resulted in 1D hierarchical self‐assembly behavior in the aqueous phase, leading to the formation of ultralong nanobelts, or spring‐like helices, with tunable mean diameters and pitches. In aqueous dispersions the superstructures absorbed in the near‐infrared range, which enabled highly efficient conversion of photon energy into thermal energy. [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]

To enforce the interactions between polyaniline (PANI) and graphene, a facile strategy is developed in this work to fabricate the strongly coupled hybrids of PANI nanofibers and graphene (named as PAGs) by introducing different diamines to functionalize graphene oxide. As the electrode material in a two-electrode supercapacitor (SC), the ethylenediamine-functionalized hybrid (PAG-EDA) deliveries an excellent volumetric specific capacitance of 810 F cm −3 at 5 mV s −1 . The SC also manifests high cycling stability by maintaining 84.4% of the initial capacitance after 10,000 cycles. More importantly, PAG-EDA renders the SC to have both high energy density (92.15 W h kg −1 ) and high power density (182.28 kW kg −1 ), superior to most of the previously reported PANI based SC electrode materials. [ABSTRACT FROM AUTHOR]

Hierarchically porous hybrids of strongly coupled nitrogen-doped porous carbons and graphene aerogel (NPC-GA) are fabricated through the solid-state oxidation polymerization and carbonization of m -phenylenediamine on the interconnected macroporous frameworks of GA. The hierarchically porous hybrids provide abundant storage sites and short transport paths for electrolyte ions. By adjusting the pyrolysis temperature, the specific surface areas and nitrogen content of NPC-GA can be easily modified, further influencing the electrochemical performance of the hybrids. In a three-electrode system, NPC-GA electrode shows high specific capacitance of 608 F g −1 at 0.1 A g −1 in 1 M H 2 SO 4 . An all-solid-state flexible supercapacitor based on NPC-GA delivers superior energy density (12.4 Wh Kg −1 ) and power density (2432 W Kg −1 ) as well as good cycling stability (92% specific capacitance retention after 10 000 cycles). [ABSTRACT FROM AUTHOR]

Three-dimensional hybrids of cobalt oxide (CoO) and graphene frameworks are fabricated via a facile hydrothermal self-assembly process. By adjusting the time of the hydrothermal treatment, the morphologies of the CoO components can be modified from rods to nanoparticles, which further manifest influences on the electrochemical performance of the hybrids. As the anode in lithium-ion battery, the hybrid loaded with spherical CoO nanoparticles exhibits the highest reversible capacity of 1148 mA h g at 100 mA g for 100 cycles among the three samples. Even at a high current density of 5000 mA g, its reversible capacity is still kept at 600 mA h g, outperforming the reported hybrids of CoO and graphene. [ABSTRACT FROM AUTHOR]

A three-dimensional polymeric carbon nitride/graphene framework (CN/GF) was fabricated by the ionic self-assembly of graphene oxide and protonated polymeric carbon nitride nanosheets. As the cathode material in lithium-ion batteries, CN/GF showed an excellent reversible capacity of 184 mA h g−1 at 0.05 A g−1 for 150 cycles and maintained the capacity of 60 mA h g−1 at 5 A g−1. [ABSTRACT FROM AUTHOR]

In this work, the composites of nitrogen-doped graphene framework and Co 3 O 4 nanoparticles with adjustable morphologies (NG/Co 3 O 4 ) were fabricated via a surfactant-assisted hydrothermal route for first time. Three different surfactants including triblock copolymer F127, cetyltrimethyl ammonium bromide and sodium dodecyl sulfate are involved in the hybrid-assembly of graphene oxide, o -phthalonitrile and cobalt acetate in water/ethanol. Among the obtained samples, the one using F127 (NG/Co 3 O 4 -F127) manifests the most homogeneous distribution of Co 3 O 4 NPs with the size of ∼ 15 nm in the macropore-walls formed by NG. As the anode material in lithium ion battery (LIB), NG/Co 3 O 4 -F127 exhibits excellent electrochemical performance, which is superior to the other composites and most of the previously reported Co 3 O 4 based anode materials in LIBs. [ABSTRACT FROM AUTHOR]

As a novel electrocatalyst for oxygen reduction reaction (ORR), nitrogen-doped graphene aerogel supported cobalt nanoparticles (Co-NGA) is archived by a hybrid-assembly of graphene oxide (GO), o-phthalonitrile and cobalt acetate and the following thermal treatment. The hybrid-assembly process successfully combines the ionic assembly of GO sheets and Co ions with the coordination between o-phthalonitrile and Co ions, which can be converted to nitrogen doped carbon and Co nanoparticles in the pyrolysis process under nitrogen flow. Remarkable features of Co-NGA including the macroporous graphene scaffolds, high surface area, and N/Co-doping effect can lead to a high catalytic efficiency for ORR. As the results, the composites pyrolyzed at 600 °C (Co-NGA 600 ) shows excellent electrocatalytic activities and kinetics for ORR in basic media, which are comparable with those of Pt/C catalyst, together with superior durability. [ABSTRACT FROM AUTHOR]

It is highly desirable to develop electroactive organic materials and their derivatives as green alternatives of cathodes for sustainable and cost-effective lithium-ion batteries (LIBs) in energy storage fields. Herein, compact two-dimensional coupled graphene and porous polyaryltriazine-derived frameworks with tailormade pore structures are fabricated by using various molecular building blocks under ionothermal conditions. The porous nanosheets display nanoscale thickness, high specific surface area, and strong coupling of electroactive polyaryltriazine-derived frameworks with graphene. All these features make it possible to efficiently depress the dissolution of redox moieties in electrolytes and to boost the electrical conductivity of whole electrode. When employed as a cathode in LIBs, the two-dimensional porous nanosheets exhibit outstanding cycle stability of 395 mAh g−1 at 5 A g−1 for more than 5100 cycles and excellent rate capability of 135 mAh g−1 at a high current density of 15 A g−1. [ABSTRACT FROM AUTHOR]

Hierarchically porous composites with mesoporous carbon wrapping around the macroporous graphene aerogel can combine the advantages of both components and are expected to show excellent performance in electrochemical energy devices. However, the fabrication of such composites is challenging due to the lack of an effective strategy to control the porosity of the mesostructured carbon layers. Here an interface-induced co-assembly approach towards hierarchically mesoporous carbon/graphene aerogel composites, possessing interconnected macroporous graphene networks covered by highly ordered mesoporous carbon with a diameter of ≈9.6 nm, is reported. And the orientation of the mesopores (vertical or horizontal to the surface of the composites) can be tuned by the ratio of the components. As the electrodes in supercapacitors, the resulting composites demonstrate outstanding electrochemical performances. More importantly, the synthesis strategy provides an ideal platform for hierarchically porous graphene composites with potential for energy storage and conversion applications. [ABSTRACT FROM AUTHOR]

In this work, a novel strategy to fabricate ternary MoS 2 /SiO 2 /graphene hybrids (MSGs) was developed by incorporating amorphous SiO 2 with MoS 2 and graphene nanosheets. Serving as anode material in lithium ion batteries, the inert silica component can effectively prevent the pulverization caused by the inner-plane volume expansion of MoS 2 . It turns out that MSGs with ∼40 wt% of SiO 2 and ∼42 wt% of MoS 2 manifest the capacity stabilized at 1060 mAh g −1 for more than 100 cycles at the current density of 0.1 A g −1 . Further, this MSG electrode maintains the specific capacity of 580 mAh g −1 at an ultrahigh current density of 8 Ag −1 , which outperforms those of the reported MoS 2 and MoS 2 /graphene hybrids. [ABSTRACT FROM AUTHOR]

The cover page of the journal "A Journal of the Gesselschaft Deutscher Chemiker Angewandte Chemie" is presented.

Abstract: The development of metal-free catalyst for oxygen reduction reaction (ORR) is one of the most challenging tasks in fuel cells. Heteroatom doped graphenes have been recognized as the promising candidate. In this work, we have developed a one-pot hydrothermal approach towards three-dimensional nitrogen and sulfur co-doped graphene frameworks (N/S-GFs) employing graphene oxide and ammonium thiocyanate as the precursors. N/S-GFs manifest excellent catalytic behavior with mainly four electron transfer pathway in ORR in alkaline condition. [Copyright &y& Elsevier]

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]

In article number 1606269, Haiqing Liu, Dongqing Wu, Xinliang Feng, and co‐workers develop a lyotropic liquid crystal based assembly strategy to fabricate composite films of vanadium pentoxide nanobelts and graphene oxide sheets. The obtained composite films possess highly oriented layered structures, high electrical conductivity, good mechanical stability, and excellent flexibility, which allows their application as high performance electrodes in flexible energy storage devices. [ABSTRACT FROM AUTHOR]

In this work, a novel soft-hard template method towards the direct fabrication of graphene films on silicon/silica substrate is developed via a tri-constituent self-assembly route. Using cetyl trimethyl ammonium bromide (CTAB) as a soft template, silica (SiO2) from tetramethoxysilane as a hard template, and pyrene as a carbon source, the self-assembly process allows the formation of a sandwich-like SiO2/CTAB/pyrene composite, which can be further converted to high quantity graphene films with a thickness of ~1 nm and a size of over 5 μm by thermal treatment. The morphology and thickness of the graphene films can be effectively controlled through the adjustment of the ratio of pyrene to CTAB. Furthermore, a high nonlinear refractive index n2 of ~10−12 m2 W−1 is measured from graphene/silica hybrid film, which is six orders of magnitude larger than that of silicon and comparable to the graphene from chemical vapor deposition process. [ABSTRACT FROM AUTHOR]