The preparation and optoelectronic response of flexible composites via noncovalent coupling of quantum dots to chemically converted graphene is presented. The photoinduced charge transfer is confirmed by photoconductivity measurements and the photosensitivity is improved with increasing loadings of quantum dots. This opens up a new effective route to form composites for future large‐area flexible and transparent optoelectronic devices.

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We report that gold thermally deposited onto n-layer graphenes interacts differently with these substrates depending on the number layer, indicating the different surface properties of graphenes. This results in thickness-dependent morphologies of gold on n-layer graphenes, which can be used to identify and distinguish graphenes with high throughput and spatial resolution. This technique may play an important role in checking if n-layer graphenes are mixed with different layer numbers of graphene with a smaller size, which cannot be found by Raman spectra. The possible mechanisms for these observations are discussed.

RNA-Puzzles is a collective endeavor dedicated to the advancement and improvement of RNA 3D structure prediction. With agreement from crystallographers, the RNA structures are predicted by various groups before the publication of the crystal structures. We now report the prediction of 3D structures for six RNA sequences: four nucleolytic ribozymes and two riboswitches. Systematic protocols for comparing models and crystal structures are described and analyzed. In these six puzzles, we discuss (i) the comparison between the automated web servers and human experts; (ii) the prediction of coaxial stacking; (iii) the prediction of structural details and ligand binding; (iv) the development of novel prediction methods; and (v) the potential improvements to be made. We show that correct prediction of coaxial stacking and tertiary contacts is essential for the prediction of RNA architecture, while ligand binding modes can only be predicted with low resolution and simultaneous prediction of RNA structure with accurate ligand binding still remains out of reach. All the predicted models are available for the future development of force field parameters and the improvement of comparison and assessment tools.

Self-assembled, one-dimensional nanostructures of N,N′-bis(2-(trimethylammonium iodide)ethylene)perylene-3,4,9,10-tetracarboxyldiimide (PTCDI-I) with tunable morphologies were successfully prepared by a facile evaporation method. PTCDI-I nanotubes with diameters of approximately 100-300 nm were obtained by the evaporation of the aqueous solution of PTCDI-I, while long nanorods with diameters of approximately 200-300 nm were produced by slow evaporation of the methanolic solution of PTCDI-I. Studies of the nanostructures formed at different stages suggested that the formation of nanotubes and nanorods could be ascribed to different crystallization processes from different solutions. The PTCDI-I nanostructures were redox-active, and fourprobe measurements based on a single nanotube or nanorod exhibited resistance decreased by 2 to 3 orders of magnitude after being exposed to reducing agents such as hydrazine or phenylhydrazine. Such high resistance modulations indicate that these nanostructures will be useful as building blocks for electronic nanodevices and sensors.

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As a new carbon allotrope, the recently fabricated graphdiyne has attracted much attention due to its interesting two-dimensional character. Here we demonstrate by multiscale computations that, unlike graphene, graphdiyne has a natural band gap, and simultaneously possess high electrical conductivity, large Seebeck coefficient, and low thermal conductivity. At a carrier concentration of 2.74×10 11 cm -2 for holes and 1.62×10 11 cm -2 for electrons, the room temperature ZT value of graphdiyne can be optimized to 3.0 and 4.8, respectively, which makes it an ideal system to realize the concept of "phonon-glass and electron-crystal" in the thermoelectric community.

After thermal deposition of silver films onto n-layer graphenes, the following results have been obtained. First, the dependence of silver morphologies on the layer number is studied via controlling the sample temperature at 298, 333, and 373 K. This can be attributed to the changes in surface properties and/or surface diffusion coefficient of n-layer graphenes at different temperatures. Second, Raman scattering of n-layer graphenes is greatly enhanced after Ag deposition and the enhancement factors depend on the layer number of n-layer graphenes. Monolayer graphene has the largest enhancement factors, and the enhancement factors decrease with layer number increasing. For graphite, almost no enhancement effect has been detected. Third, the dependences of the enhancement factors on laser wavelength, thickness, and morphologies (nanoparticle size and spacing) of silver film are also studied. The Raman enhancement observed here is mainly attributed to the coupled surface plasmon resonance (SPR) absorption of silver nanoparticles.