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Porous BiOCl micro-flowers constructed from ultrathin nanosheets with nearly 100% {001} facets exposed were selectively prepared. The exposed {001} facets terminated with a high density of oxygen atoms and are not only favorable for the adsorption of the cationic dye RhB but also can accumulate the photogenerated electrons injected from excited RhB. These electrons can be captured by O(2) and transformed to reactive oxygen species, which possess a strong photooxidative ability to degrade the dye pollutants directly and easily. Therefore, the resultant BiOCl photocatalysts exhibit superior activity for indirect dye photosensitization degradation under visible light, with a rapid degradation rate and high photostability.

In this article, organic-inorganic hybrid materials of polyaniline/α-zirconium phosphate (PANI/α-ZrP) was synthesized by in situ oxidative polymerization reaction and characterized by Fourier transformed infrared (FTIR), field-emission scanning electron microscopic (FE-SEM) and X-ray diffraction (XRD). The results showed that polyaniline (PANI) was successfully grown on the surface of α-zirconium phosphate (α-ZrP) nanoplates. The PANI/α-ZrP nanocomposites were further applied to remove methyl orange (MO), which was used as a model of organic pollutants in aqueous solution. A synergistic effect of PANI and α-ZrP on promoting the adsorption removal of MO was observed. The PANI/α-ZrP nanocomposites exhibited excellent maximum adsorption capacity toward MO (377.46 mg g(-1)), which is superior to that of PANI nanotubes (254.15 mg g(-1)) and much higher than that of many other adsorbents. The adsorption isotherms of MO can be well-fitted with the Langmuir model and the adsorption kinetics follows the pseudo-second-order model. MO adsorption decreased with increasing solution pH at pH4.0 implying that MO adsorption on PANI/α-ZrP may via electrostatic interactions between amine and imine groups on the surface of PANI/α-ZrP and MO molecules. This study implies that the hybrid materials of PANI/α-ZrP can be suggested as potential adsorbents to remove organic dyes from large volumes of aqueous solutions.

Tuck-yun Cheang1,*, Bing Tang1,*, An-wu Xu2, Guang-qi Chang1, Zuo-jun Hu1, Wei-ling He1, Zhou-hao Xing2, Jian-bo Xu1, Mian Wang1, Shen-ming Wang11Department of Vascular Surgery, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, China; 2Division of Nanomaterials and Chemistry, Hefei National Laboratory for Physical Sciences at Microscale, University of Science and Technology of China, Hefei, China *Both authors contributed equally to this workAbstract: Nanoparticles have an enormous potential for development in biomedical applications, such as gene or drug delivery. We developed and characterized aminopropyltriethoxysilane-functionalized silicon dioxide nanoparticles (APTES-SiNPs) for gene therapy. Lipofectamine® 2000, a commonly used agent, served as a contrast. We showed that APTES-SiNPs had a gene transfection efficiency almost equal to that of Lipofectamine 2000, but with lower cytotoxicity. Thus, these novel APTES-SiNPs can achieve highly efficient transfection of plasmid DNA, and to some extent reduce cytotoxicity, which might overcome the critical drawbacks in vivo of conventional carriers, such as viral vectors, organic polymers, and liposomes, and seem to be a promising nonviral gene therapy vector.Keywords: aminopropyltriethoxysilane, silicon dioxide nanoparticles, Lipofectamine® 2000, gene therapy vector, nanomedicine

Teflon films, made from polytetrafluoroethylene (PTFE), are widely known hydrophobic materials. In this paper, we utilize Teflon films as concentrators to construct active surface-enhanced Raman scattering (SERS) substrates to achieve a higher sensitivity for SERS detection. The fabrication method is simple via directly depositing a drop of silver colloidal solution on a piece of commercial Teflon film and drying it under ambient conditions. SERS measurements are carried out on Rhodamine6G (R6G) molecules, showing strong enhanced SERS signals even at a concentration of 10−15 M and allowing single-molecule detection. Silver nanoparticles (Ag-NPs) supported on the Teflon films exhibit a higher SERS enhancement and better reproducibility compared with that on glass slides. Such a high enhancement effect is primarily attributed to the hydrophobic condensation effect of Teflon films towards both silver colloids and R6G molecules, thus causing the aggregation of Ag-NPs for more “hot-spots” and delivering R6G molecules to the hot-spot areas thereby overcoming the limit of diffusion.

Nanostructures with concave surfaces are not common, and their synthesis is still challenging. In this paper, we have successfully synthesized two kinds of five-fold-twinned Au decahedra and dodecagonal plates by changing the reaction conditions. 40 high-index {221} facets were observed in the concave decahedron. The truncated decahedral gold nanocrystals (NCs) with a large size of 250-350 nm were obtained for the first time, which breaks the assumption that the truncated five-fold-twinned Au nanoparticles (NPs) can only be obtained with a size below 5 nm. The growth mechanism and the evolution process of the gold nanostructures were discussed. This work provides a facile way to synthesize concave decahedra, truncated decahedra and dodecagonal plates with controlled nanostructures.