Summary A hybrid nanostructure with partially reduced graphene oxide (rGO) and carbon nanofibers (CNFs) was fabricated and used as supercapacitor electrodes. A straightforward, environmentally friendly, and low‐cost microwave‐assisted reduction process was developed for the synthesis of rGO/CNF hybrid structures. The fabricated supercapacitor devices showed a specific capacitance of 95.3 F g−1 and a superior long‐term cycling stability. A capacitance retention of more than 97% after 11 000 galvanostatic charge discharge cycles was obtained. These and other results reported in this paper indicate that high‐rate, all‐carbon, rGO/CNF hybrid nanostructures are highly promising supercapacitor electrode materials.

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Two copper‐based Cu3(btc)2 and Cu(Im)2 metal–organic frameworks are synthesized and annealed to form nanoporous Cu/Cu2O@C and Cu@N‐C nanoparticles for utilization as catalysts in the reduction reaction of aromatic nitro compounds to aromatic amines. All synthesized MOF compounds and MOF‐derived nanoparticles are characterized using XRD, Raman spectroscopy, TGA, SEM‐EDX, and XPS methods. Also, the pore‐size distribution and surface area of the MOF‐derived Cu/Cu2O@C and Cu@N‐C nanoparticles are characterized by the BJH and BET methods. After characterization, the catalysts Cu/Cu2O@C and Cu@N‐C are catalytically tested for the reduction reactions of various aromatic nitro compounds chemically by monitoring with a UV/Vis spectrometer. Both catalysts exhibit remarkable results compared with those in the literature. Also, the Cu/Cu2O@C catalyst shows better results than the Cu@N‐C catalyst.

Titanate nanotubes are promising materials for Li-ion battery anodes because of their special morphology and high specific surface areas. These titanates provide high rate capability and low volume expansion upon lithiation. More importantly, their tubular structure helps the transport of ions through the crystal. In this study, we synthesized elongated titanate nanotubes and modified their interlayer distances by changing the pH (2-13). For the structural characterization XRD, BET, SEM and TEM techniques were used. In addition, the effect of interlayer distance on energy capacity and rate capability was investigated. The highest interlayer distance was obtained at pH 10 and with decreasing pH, the interlayer distance dropped until reaching a pH value of 4. Conversely, the specific surface area reached its maximum value of 204 m(2) g(-1) at a pH of 4. Different from anatase (TiO2), titanate nanotubes had broad peaks in cyclic voltammograms suggesting a pseudocapacitive behavior. The sloping profiles of potential-capacity results also supported the pseudocapacitive property. For the titanate nanotubes obtained at pH 10, an initial discharge capacity of 980 mAh g(-1) was achieved. More importantly, titanate nanotubes showed exceptional rate capabilities and the capacities stayed almost constant at high current rates because of their elongated structure. It was found that the interlayer distance and the elongated structure play an important role in the electrochemical performance of the material.

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