Jingbo Mu

Solvothermal synthesis of hierarchical Co3O4 flower-like microspheres for superior ethanol gas sensing properties

In this paper, hierarchical Co3O4 flower-like microspheres have been successfully synthesized on the basis of morphology-conserved transformation method. The key step of this method is to construct flower-like microstructures of the cobalt-containing precursors via manipulating the synthetic parameters in a facile ethylene glycol mediated solvothermal reaction. The as-prepared flower-like microspheres are formed from the assembly of many two-dimensional nanosheets, accompanied by an outside-in dissolution and recrystallization process. Finally, hierarchical Co3O4 microspheres with conserved flower-like morphology are obtained through the moderate calcination. When evaluated as a gas sensor, the obtained Co3O4 flower-like microspheres exhibit a good response and sensitivity towards ethanol gas, suggesting their promising potential for gas sensors application.

TWO-DIMENSIONAL NANOSHEETS-ASSEMBLED FLOWER-LIKE Co3O4 MICROSPHERES AND THEIR GAS SENSING PERFORMANCES

In this paper, three-dimensional (3D) Co3O4 flower-like microspheres have been successfully synthesized via a facile ethylene glycol (EG)-mediated solvothermal method followed by calcination. The as-prepared flower-like precursors microspheres are formed from the assembly of 2D nanosheets in the presence of hexadecyltrimethylammonium bromide (CTAB). The flower-like architectures of the prepared precursors could be tailored by changing the amount of CTAB. Furthermore, when evaluated as a gas sensor, the obtained Co3O4 flower-like microspheres exhibit a good response and sensitivity toward ethanol gas, suggesting their promising potential for gas sensors application.

Adhesion and friction studies on silicon dioxide nanoparticle-textured surfaces prepared by the spin-coating process

Silicon dioxide nanoparticle-textured surfaces were prepared by the spin-coating process. The adhesion and friction properties of the nanoparticle-textured surfaces were investigated using an atomic force microscope colloidal probe. Experimental results revealed that the nanoparticle-textured surfaces can significantly reduce adhesive and friction forces compared with a flat surface. The main reason for this phenomenon was that the nanotexture can reduce contact area between the sample surface and the colloidal probe. The relationships between surface root mean square (RMS) roughness, packing density, and spinning rate were also discussed. The effects of surface RMS roughness and packing density on the adhesion and friction behaviors of the nanotextured surfaces were investigated. The adhesive and friction forces of the nanoparticle-textured surfaces decreased with increasing packing density. The friction forces of the nanoparticle-textured surfaces increased with increasing applied load and sliding velocity. This approach should be applied to new developments in nanosystems to reduce adhesive and friction forces between contact pairs.

Ag/MnO2 Nanorod as Electrode Material for High-Performance Electrochemical Supercapacitors

A one-dimensional hierarchical Ag nanoparticle (AgNP)/MnO2 nanorod (MND) nanocomposite was synthesized by combining a simple solvothermal method and a facile reduction approach in situ. Owing to its high electrical conductivity, the resulting AgNP/MND nanocomposite displayed a high specific capacitance of 314 F g-1 at a current density of 2 A g-1, which was much higher than that of pure MNDs (178 F g-1). Resistances of the electrolyte (Rs) and charge transportation (Rct) of the nanocomposite were much lower than that of pure MNDs. Moreover, the nanocomposite exhibited outstanding long-term cycling ability (9% loss of initial capacity after 1000 cycles). These results indicated that the nanocomposite could serve as a promising and useful electrode material for future energy-storage applications.

Preparation of Nano-Convex and Nano-Concave-Patterned Polyimide Surfaces and Their Nano-Tribological Behavior

In this work, nano-convex-patterned polyimide surface (notated as 1-sample) and nano-concave-patterned polyimide surface (notated as 2-sample) were prepared by self-assembly and etching. Atomic for...

Synthesis of Novel Hollow Copper Oxide Micro-Flowers Assembled by Nanoparticles and Their Improved Catalytic Performances for the Synthesis of Organosilane

In this work, novel sisal-like hollow CuO micro-flowers were synthesized via a facile solvothermal reaction followed by calcination. The flower-like shells of hollow CuO are constructed by irregular petals interweaving each other, which are composed of aggregated nanoparticles with sizes of ca. 18nm. It was found that the flower-like morphology of the as-synthesized CuO products can be controlled via finely tuning the solvothermal reaction time. When used as catalysts for the synthesis of organosilane, the obtained hollow CuO micro-flowers exhibit better catalytic performances than the commercial CuO powders. Superior catalytic performances are due to the hollow and flower-like structures of the as-synthesized CuO products, which can promote the synthetic reaction for the organosilane, that is, the gas–solid contacting reaction occurred among the reaction gas, solid silicon powders and CuO catalysts. Our work will be helpful to design and develop the novel Cu-based nanocatalysts for the synthesis of organosilane.