Chen-Xu Zhang

Zn2SnO4-Reduced Graphene Oxide Nanohybrids for Visible-Light-Driven Photocatalysis

Zn2SnO4-reduced graphene oxide photocatalysts were synthesized by using SnCl4 5H2O, Zn(NO3)2 · 6H2O and graphene oxide via hydrothermal process. The structure, morphology, specific surface area and photo response of the as-prepared nanocomposites were characterized by X-ray diffraction, Transmission electron microscopy, UV-vis diffuse reflectance spectra, Brunauer-emmett-teller surface area measurement and Photoluminescence emission spectra. Experimental results showed that the Zn2SnO4 nanoparticles, with 20-30 nm a size range, were uniformly dispersed on the surfaces of reduced graphene oxide. Moreover, the as-prepared Zn2SnO4-reduced graphene oxide photocatalysts exhibited enhanced photocatalytic activities for degradation of Rhodamine B compared to those of pure Zn2SnO4. When the amount of reduced graphene oxide was 4 wt%, it showed the highest photocatalytic efficiency of 99.7% for 240 min, and the photocatalytic efficiency was still 98.5% after it was recycled 4 times. It also possessed the band gap of 2.48 eV and specific surface area of 58.1 m2 g-1.

Preparation and Characterization of Nanosized Bi-Doped SnO2/Reduced Graphene Oxide 3D Hybrids for Visible-Light-Driven Photocatalysis

The nanosized Bi-doped SnO2/reduced graphene oxide 3D hybrids have been synthesized via one-step hydrothermal method. The structures, morphologies, photocatalytic activities of the as-prepared samples were discussed, respectively. The formation mechanism of the as-prepared hybrids was also proposed. Experimental results indicated that the usage amount of Bi2Sn2O7 obviously affected the photocatalytic performance of the as-prepared products. When it was 450 mg, the as-prepared sample possessed the band gap energy of 1.9 eV and the photocatalytic efficiency of 90% in 210 min for degradation of rhodamine B solution. In addition, triethylene tetramine and the as-prepared carbon hydrogel could act as reductant to synergistically reduce Bi2Sn2O7 into Bi-doped SnO2 particles during the formation of the hybrids.

Isothermal Crystallization Properties of Polyamide 6 / Hexagonal Boron Nitride Nanocomposites

ABSTRACT Hexagonal boron nitride was adopted as a heterogeneous nucleation agent to fabricate polyamide 6 based nanocomposite films via a solution casting method. Isothermal crystallization behaviors of the as-prepared films were measured by using differential scanning calorimetry. Results showed that both the crystallization temperature and fillers loading greatly affected the crystallization process of the as-prepared samples. The crystallization nucleation and growth mechanism did not change during the initial stage of crystallization. The halftime of crystallization gradually increased with increasing crystallization temperature. Moreover, it decreased first and then increased with increasing the fillers loading at low crystallization temperature, while it decreased gradually at high crystallization temperature. Furthermore, the crystallization activation energy of the as-prepared samples gradually decreased with increasing fillers loading.