Qixun Guo

Preparation and characterization of γ-AlOOH nanotubes and nanorods

A solution-phase reaction under hydrothermal conditions at relatively low temperature is first put forward for the preparation of ?-AlOOH nanotubes and nanorods, on the basis of the possible strategy that the 2D framework structure of ?-AlOOH containing lamellae could provide orientation for the growth of 1D nanostructures. X-ray diffraction?(XRD) patterns, transmission electronic microscope?(TEM) images, Fourier transform infrared?(FTIR) spectra, and photoluminescence?(PL) spectra were used to characterize the products. A possible formation mechanism of nanotubes and nanorods from lamellar precursor is proposed.

Cubic to tetragonal phase transformation in cold-compressed Pd nanocubes.

Pd nanocubes with an average side length of approximately 10 nm were compressed up to 24.8 GPa in a diamond-anvil cell (DAC). In situ synchrotron X-ray diffraction was used to monitor structural changes, and a face-centered cubic (fcc) to face-centered tetragonal (fct) distortion was observed for the first time. This novel discovery not only provides new insights into the pressure-induced behavior of faceted nanocrystals of palladium and other noble metals but also gives guidance for finding new phases in close-packed metals.

Synthesis of carbon nitride nanotubes with the C3N4 stoichiometry via a benzene-thermal process at low temperatures

In this communication, we first report the direct synthesis of high-quality carbon nitride nanotubes (CNNTs) with inner diameters of 50-100 nm and wall thicknesses of 20-50 nm with the C(3)N(4) stoichiometry on a high-yield of 40%via a simple benzene-thermal process involving the reaction of C(3)N(3)Cl(3) with NaN(3) in a Teflon-lined autoclave at 220 [degree]C without using any catalyst or template.

Synthesis of high quality inorganic fullerene-like BN hollow spheres via a simple chemical route

High quality inorganic fullerene-like boron nitride hollow spheres (100-200 nm) have been successfully synthesized via a simple chemical route with a 30-40% yield of BN hollow spheres.

Structural characterization and electrochemical performance of macroporous graphite-like C3N3 prepared by the Wurtz reaction and heat treatment

Macroporous graphite-like C3N3 (g-C3N3) with s-triazine rings as building blocks was synthesized by the Wurtz reaction of C3N3Cl3 with sodium in autoclaves. The structure and electrochemical performance as a lithium ion battery anode of the obtained samples were then investigated. Structural characterization results reveal that the as-prepared samples show characteristic 002 basal plane diffractions and s-triazine rings structures with an N/C atomic ratio of about 1 : 1, indicating that the theoretical g-C3N3 has been successfully prepared. It was found that the heat treatment can help improve the initial coulombic efficiency and reversible capacity due to the decrease of the nitrogen content and the partial degradation and rearrangement of triazine rings. When used as an anode for Li-ion batteries, the g-C3N3 formed by heat treatment up to 600 °C exhibits a relatively good reversible capability and cycling stability (197.8 mA h g−1 at 100 mA g−1), with measurements superior to those of reported bulk g-C3N4 and other graphite-like carbon nitride analogues.