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ZnS nanobelts have been synthesized by a simple thermal evaporation method in a N2 atmosphere containing a small amount of CO and H2 gases. The synthesized ZnS nanobelts have a width in the range of 40 to 120 nm, a thickness of 20 nm, and a length of several micrometers. The nanobelts are single crystals with a hexagonal wurtzite structure growing along the [001] direction. A vapor–solid process is proposed for the formation of such nanobelts. The as-prepared nanobelts shows two emission bands, around 450 and 600 nm.

An a-cobalt hydroxide with an interlayer spacing of 12.65 A ˚has been synthesized in sheet shapes with dimensions of 100-120 nm with the aid of sonication. Acetate anions are intercalated into the interlayer region of the as-prepared a-cobalt hydroxide in the form of a free ion state. b-Cobalt hydroxide has also been prepared and formed as crystallized thin hexagonal platelets with a diameter of 100 nm. Pure cobalt oxyhydroxide with a particle size of 10-30 nm has also been obtained. Powder X-ray diffraction, thermogravimetric analysis, FT-IR spectroscopy, transmission electron microscopy, as well as elemental analysis, have been used in the characterization of the as-prepared samples.

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This study focuses on the preparation of a CaTiO3-coated nano-CaO-based CO2 adsorbent (CaTiO3/nano-CaO) for the improvement of sorption properties. The CaTiO3-coated nano-CaO adsorbent was prepared by forming Ti(OH)4 from the hydrolysis of titanium alkoxide in a nano-CaCO3 suspended solution. The resulting Ti(OH)4-coated nano-CaCO3 was then heated and calcined. Test results from transmission electron microscopy and scanning electron microscopy with energy dispersive X-ray spectroscopy show that an obvious film of TiO2 was formed on the surface of nano-CaCO3 after heating. X-ray diffraction analysis also showed that the nano-CaTiO3 layer was formed at 750 °C, a calcination temperature that causes the reaction of TiO2 with nano-CaO. The cyclic tests of reactive sorption capacity were conducted in a thermogravimetric analyzer under the following conditions: 0.02 MPa CO2 partial pressure, carbonation temperature of 600 °C, and calcination temperature of 750 °C. Test results showed that CaTiO3 coated onto the nano-CaO caused a significant improvement in the durability of the capacity for reactive sorption. Nano-CaO that had an optimum content of 10 wt % TiO2 showed significantly stable CO2 reactive sorption capacity (5.3 mol/kg) after 40 cyclic carbonation−calcination runs compared to the reactive sorption capacity of CaO without TiO2 coating (3.7 mol/kg).

ZnS-Zn nanocables and ZnS nanotubes have been synthesized by a thermochemical process in a simple and safe way. The as-prepared nanocables consist of a single crystal Zn core with a diameter of 20 nm and a polycrystalline ZnS sheath with a thickness of 8 nm. The evaporation of the Zn core leads to the formation of ZnS nanotubes.

This work reports the nanocomposites of graphitic nanofibers (GNFs) and carbon nanotubes (CNTs) as the electrode material for supercapacitors. The hybrid CNTs/GNFs was prepared via a synthesis route that involved catalytic chemical vapor deposition (CVD) method. The structure and morphology of CNTs/GNFs can be precisely controlled by adjusting the flow rates of reactant gases. The nest shape entanglement of CNTs and GNFs which could not only have high conductivity to facilitate ion transmission, but could also increase surface area for more electrolyte ions access. When assembled in a symmetric two-electrode system, the CNTs/GNFs-based supercapacitor showed a very good cycling stability of 96% after 10 000 charge/discharge cycles. Moreover, CNTs/GNFs-based symmetric device can deliver a maximum specific energy of 72.2 Wh kg−1 at a power density of 686.0 W kg−1. The high performance of the hybrid performance can be attributed to the wheat like GNFs which provide sufficient accessible sites for charge storage, and the CNTs skeleton which provide channels for charge transport.