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In this study, ruthenium nanoparticles (RuNPs) were successfully decorated on graphene nanosheets (GNSs) for the very first time by a dry synthesis method. The resultant material (GNS-RuNPs) was used as a nanocatalyst for the aerial oxidation of alcohols after being optimized. The scope of the catalytic system was extended with various aliphatic, aromatic, alicyclic, benzylic, allylic, amino, and heterocyclic alcohols. The 0.036 mol % (5 mg) of catalyst was enough for aerial oxidation of alcohols, the lowest amount of catalyst so far reported. The proposed nanocatalyst is highly chemoselective, heterogeneous, and reusable. The GNS-RuNPs were separated out from the reaction mixture and analyzed by transmission electron microscopy (TEM), X-ray diffraction (XRD), Raman, and scanning electron microscopy-energy dispersive spectrometry (SEM-EDS); the results revealed that the nanocatalyst is physically as well as chemically stable. Owing to the high stability of used catalyst (u-GNS-RuNPs), it was further applied in transfer hydrogenation, after suitable modifications. We obtained ruthenium oxide nanorod hybrid GNSs (u-GNS-RuO2NRs) from u-GNS-RuNPs by simple calcination. The catalytic activity of u-GNS-RuO2NRs toward the transfer hydrogenation of various aromatic, alicyclic, and heterocyclic ketones was found to be excellent.

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Protein based scaffolds are preferred for tissue engineering and other biomedical applications owing to their unique properties. Zein, a hydrophobic protein, is a promising natural biodegradable polymer. However, electrospun structures prepared from Zein have poor mechanical and wetting properties. Cellulose acetate (CA) is an economical, biodegradable polymer having good mechanical and water retention properties. The aim of present study was to fabricate a novel material by electrospinning Zein/CA blends. A series of Zein/CA hybrid nanofibers were electrospun and characterized. The attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR) spectrum showed the characteristic peaks of both Zein and CA, and was composition dependent. The X-ray photoelectron spectrometry (XPS) curves of Zein/CA blends demonstrated a similar profile to that of pristine Zein nanofibers. Thermogravimetric analyser (TGA) studies confirmed that the Zein/CA hybrid nanofibers have a higher degradation temperature and better thermal stability than pristine Zein nanofibers. The glass transition temperature (T g ) of Zein/CA hybrid nanofibers was also increased in comparison to pure Zein nanofibers as revealed by differential scanning calorimetry (DSC). Zein/CA hybrid nanofibers have hydrophilic surface character as revealed by water contact angle (WCA) analysis. SEM imaging showed bead free morphology of the electrospun nanofibers. The average nanofiber diameter decreased for Zein/CA blends with increasing CA composition. The electrospun Zein/CA hybrid nanofibers may be used for tissue engineering scaffolds and for other biomedical materials.