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Nanomaterials, such as single‐walled carbon nanotubes (SWCNTs) and graphenes, can be readily gelled using bi‐ or multi‐functional reagents as crosslinkers. This study reports a new reaction of monofunctional acetylenes with negatively charged SWCNTs (nanotubides), prepared by reduction. Mono‐acetylenes (e. g. phenylacetylene (PAc) and diphenyl acetylene (DiPAc)) are introduced as crosslinkers to form all‐carbon SWCNT organogels at room temperature. The resulting isolated SWCNT aerogels have a density of ∼4.5–5.5 mg cm−3. Raman spectroscopy and thermogravimetric analysis suggest a covalent surface modification (∼1 functional group per 110 (PAc) and 712 (DiPAc) SWCNT carbon atoms). Significantly, the acetylene reaction does not consume all available negative charges. The SWCNT organogel is still reactive after crosslinking and can reduce a stable gold complex, chloro(triphenylphosphine)gold (I), to form AuNPs (∼12–14 nm), suggesting the formation of a living nanotubide organogel intermediate, suitable for a range of secondary reactions. Mono‐acetylenes can crosslink other negatively charged molecular systems, and surface decoration of the aerogels with other metal NPs is anticipated. [ABSTRACT FROM AUTHOR]

N‐doped sites at carbon nanotubes and graphene trigger the spontaneous decoration of bimetal (Pt and Pd) particles by the facile electroless redox reaction. The created hybrid catalyst yields remarkable current density (≈2.44 mA cm−2), lower onset potential (≈0.13 V), higher electron transfer number ≈4), and long‐term stability for oxidation–reduction reactions. [ABSTRACT FROM AUTHOR]

Review: 174 refs. [ABSTRACT FROM AUTHOR]

Abstract: Graphene synthesis was performed on Fe foil at low temperature. A 100 μm-thick Fe foil as a catalyst and acetylene as a hydrocarbon source were used for graphene growth. With a low acetylene flow rate (5 sccm) and short exposure time (5 min), single- to few-layer graphene sheets partially covering the Fe substrate were obtained. With sufficient exposure times (15–30 min), and acetylene flow rates (25–50 sccm), continuous graphene layers were obtained at temperatures ranging from 600 °C to 800 °C. The measured Raman spectra showed that defects decreased with an increasing synthesis temperature. Even though the 2D and G peak intensities of the Raman spectrum appeared to be similar, the thickness of the graphene layers synthesized at 700 °C and 750 °C was measured to be as thick as ∼15 nm and ∼29 nm, respectively. Considering that the estimated number of graphene layers should be less than 2–3 without creating stacking disorder between the interlayers, it appears that an ordered stacking, (i.e., ABAB stacking) and therefore electronic coupling between layers, may not occur in the synthesized graphene layers on Fe foil under those process conditions. [Copyright &y& Elsevier]

As human society develops, electronic/optoelectronic devices are further required to be foldable, wearable, and even visually comfortable, but simultaneous achievement of both performance and comfort is a tough task. Here, we first report all-two-dimensional (2D) bis (trifluoromethanesulfonyl)-amide (TFSA)-doped graphene (GR) (TFSA-GR)/MoS 2 / triethylene tetramine (TETA)-doped GR (TETA-GR) vertical-heterostructure semitransparent photodetectors (PDs) on rigid/flexible substrates. The PD exhibits 0.128 A/W responsivity (R) and 1.69 × 109 cm Hz1/2/W detectivity at 532 nm wavelength with average visible transmittance being 58%. By adding an Al reflective mirror to the semitransparent PD, the R is improved to 0.137 A/W. The unencapsulated PD maintains ~75% of its initial R under 25 °C/30% relative humidity for 1000 h. The flexible PD shows excellent bending stability by maintaining 32% of its initial R even after 2000 bending cycles at a radius of curvature of 2 mm. These results suggest that the all-2D TFSA-GR/MoS 2 /TETA-GR vertical heterostructures are very promising for their applications in flexible, foldable, and/or semitransparent electronic/optoelectronic appliances. • First report on all-two-dimensional graphene/MoS 2 /graphene vertical heterostructures. • The heterostructures are useful for the semitransparent/flexible photodetector application. • Visible transparency and long-term/bending stabilities are 58% and 75/32%, respectively. [ABSTRACT FROM AUTHOR]

We report a remarkably rapid methodfor assembling pristine grapheneplatelets into a large area transparent film at a liquid surface.Some 2–3 layer pristine graphene platelets temporally solvatedwith N-methyl-2-pyrrolidone (NMP) are assembled atthe surface of a dilute aqueous suspension using an evaporation-drivenRayleigh-Taylor instability and then are driven together by Marangoniforces. The platelets are fixed through physical binding of theiredges. Typically, 8-cm-diameter circular graphene films are generatedwithin two minutes. Once formed, the films can be transferred ontovarious substrates with flat or textured topologies. This interfacialassembly protocol is generally applicable to other nanomaterials,including 0D fullerene and 1D carbon nanotubes, which commonly sufferfrom limited solution compatibility. [ABSTRACT FROM AUTHOR]