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A key task in today's inorganic synthetic chemistry is to develop effective reactions, routes, and associated techniques aiming to create new functional materials with specifically desired multilevel structures and properties. Herein, we report an ultrathin two‐dimensional layered composite of graphene ribbon and silicate via a simple and scalable one‐pot reaction, which leads to the creation of a novel carbon‐metal‐silicate hybrid family: carbosilicate. The graphene ribbon is in situ formed by unzipping carbon nanotubes, while the ultrathin silicate is in situ obtained from bulk silica or commercial glass; transition metals (Fe or Ni) oxidized by water act as bridging agent, covalently bonding the two structures. The unprecedented structure combines the superior properties of the silicate and the nanocarbon, which triggers some specific novel properties. All processes during synthesis are complementary to each other. The associated synergistic chemistry could stimulate the discovery of a large class of more interesting, functionalized structures and materials. [ABSTRACT FROM AUTHOR]

In this paper, a series of highly dispersed CeO2 catalysts on graphene oxide sheets (GO) were prepared by simple impregnation method. The catalysts were applied for selective catalytic reduction(SCR) of NO with NH3. Compared with the 5 wt %CeO2/GO and 15 wt %CeO2/GO catalysts, 10 wt %CeO2/GO catalyst exhibited better catalytic performance in the temperature range of 175–325 °C and higher SO2 resistance at 275 °C. The as‐prepared catalysts were characterized by TEM, AFM, XPS, XRD, BET, H2‐TPR, NH3‐TPD and FT‐IR, respectively. The characterization results indicated that 10 wt %CeO2/GO catalyst possessed larger specific surface area, enriched surface acidic sites, high redox capacity and oxygen vacancies. In addition, Ce3+ on the surface of CeO2/GO catalyst could reduce the oxidation property of SO2, thus improving the SO2 resistance of the catalyst. Meanwhile, the stability of 10 wt %CeO2/GO catalyst was tested. At 275 °C, the NO conversion maintained at 94 % within 30 hours, suggesting the excellent stability. [ABSTRACT FROM AUTHOR]

Graphene oxides (GOs) are popular catalyst supports for precious metals in nanoparticle form. The hydrogen oxidation reaction (HOR) and the hydrogen evolution reaction (HER) on individual GO platelets decorated with Pd nanoparticles (Pd/GOs) were investigated. The results suggest that the catalytic activity is confined to the zone physically close to the point of electrical contact between platelet and electrode with just a fraction of the platelet active. [ABSTRACT FROM AUTHOR]

Abstract: The introduction of surface functional groups onto graphene can provide additional pseudocapacitance for supercapacitors. However, the compensation for the loss of electrical conductivity arising from the disruption of the conjugated system remains a big challenge. Here, a novel strategy is reported for the design of oxygen clusters distributed in graphene with “paddy land” structure via a low‐temperature annealing process. Moreover, the distribution, content, and variety of oxygen groups and the conductivity of reduced graphene oxide (RGO) can be easily adjusted by annealing temperature and time. First‐principles calculations demonstrate that “paddy land” structure exhibits conjugated carbon network, ultralow HOMO–LUMO gap, and long span of atomic charge values, which are beneficial for the enhanced pseudocapacitance and rate performance. As a result, the functionalized graphene (GO‐160‐8D) exhibits high specific capacitance of 436 F g−1 at 0.5 A g−1, exceeding the values of previously reported RGO materials, as well as excellent rate performance (261 F g−1 at 50 A g−1) and cycling stability (94% of capacitance retention after 10 000 cycles). The findings may open a door for finely controlling the location and density of functionalities on graphene for applications in energy storage and conversion fields via a green and energy‐efficient process. [ABSTRACT FROM AUTHOR]

Non-precious metal oxide/carbon hybrid electrocatalysts are of increasing importance for the oxygen reduction reaction (ORR). A synergistic effect is commonly used to explain the superior ORR activity exerted by metal oxide/nanocarbon hybrids, and this effect is attributed to covalently coupled interfaces between the two materials. However, the origin of the high activity, the structure, and the electrocatalytic nature of the interface remain unclear. By combining X-ray photoelectron spectroscopy with synchrotron far-infrared spectroscopy, we resolved the interface structure between spinel manganese oxide nanocrystals and graphene oxide nanoribbons, and the role of this interface in the promoted ORR. Moreover, we demonstrated the excellent ORR activity by a functional synergism of the hybrid constituents through a series of comparative electrochemical experiments. [ABSTRACT FROM AUTHOR]

With graphene oxide (GO) as ‘shape-directing’ agent, carbon aerogels with tunable hierarchical porous structure were prepared by one-step carbonization method. It was found that the content of GO had a significant effect on their pore structures. When GO loading was up to 1.43 wt‱, it possessed an ultrahigh specific surface area (SSA) of 2728 m 2 g −1 , large pore volume of 1.82 cm 3 g −1 and excellent mechanical properties. Benefiting from the high SSA and unique hierarchical porous microstructure, possible future applications of the as-obtained carbon aerogels could be in the fields of energy storage, electrochemistry, and adsorption. [ABSTRACT FROM AUTHOR]

The surface chemistry of nanocarbon support can tailor chemical properties of precious metal nanoparticle/nanocarbon hybrid catalyst in heterogeneous reactions. We report on modified reduced graphene oxide (rGO) support with ionic liquid-derived carbonaceous surface for palladium nanoparticle (Pd NPs) decoration and their actions in different heterogeneous reactions. The surface chemistry of support materials was characterized in detail, and the influence of which on the formation and distribution of metal particles was further investigated. Three different types of reactions including Suzuki-Miyaura coupling reaction, CO oxidation and phenol reduction were examined in terms of reactivity and selectivity. The roles of substituted nitrogen in graphitic lattice and grafted groups on the carbon surface were exploited. Nitrogen-doping can give rise to changes in electronic properties of supported metals, and the Lewis basicity of the doped nitrogen atoms can favor the adsorption of acidic reactants in phenol reduction. The grafted groups derived a negative impact to the Suzuki-Miyaura coupling reaction, due to the involvement of larger reactant molecules, despite that they could prevent significant sintering of Pd NPs in the CO oxidation. [ABSTRACT FROM AUTHOR]

• Palladium/graphene oxide (Pd/GO) aerogels are synthesized. • Pd/GO aerogels have large surface areas and enrich functionalities. • Pd nanoparticles are uniformly dispersed on the surface of the support. • Pd/GO aerogels have enhanced catalytic performance compared to the Pd/C. In this work, the low-loading (3 wt%) palladium/graphene oxide (Pd/GO) aerogels are facilely prepared via the lyophilisation, vacuum and reduction treatments. The Pd/GO aerogels display enhanced activity and stability in comparison to the commercial Pd/C. The enhancement of electrocatalytic performance can be attributed to the functional groups on the surfaces of the GO support, such as carbonyl and carboxyl groups, which can be tuned to interact with palladium to form active phases for the reaction. In addition, Pd nanoparticles (NPs) remain dispersed in nanoscale on the reacted catalyst. [ABSTRACT FROM AUTHOR]

• Pd/reduced graphene oxide aerogels with large surfaces and wrinkles are synthesized. • Pd/reduced graphene oxide aerogels enrich oxygen-containing functional groups. • A high proportion of Pd2+ is presented on the Pd/reduced graphene oxide aerogels. • Pd/reduced graphene oxide aerogels display an improved activity compared to the Pd/AC. • PdNPs remained well dispersed on the reacted Pd/reduced graphene oxide aerogels. In this work, Pd/reduced graphene oxide (Pd/RGO) aerogels, with large surface areas and wrinkles, are obtained through the lyophilisation, vacuum and reduction treatments. Pd/RGO aerogels exhibit higher catalytic performances and thermal stability in comparison to the reference catalyst Pd/activated carbon (Pd/AC) in the oxidation of benzyl alcohol. The surface analyses indicate that Pd/RGO aerogels possess a higher proportion of Pd2+ than the Pd/AC catalyst. Meanwhile, the oxygen-containing functional groups can modulate the interaction between palladium and the support to form active phases for the reaction. Moreover, Pd nanoparticles (PdNPs) remain well dispersed in nanoscale on the reacted Pd/RGO aerogels. [ABSTRACT FROM AUTHOR]