An Au8 Cluster Fortified by Four Ferrocenes.

Atomically precise metal clusters are now in the research spotlight, owing to the precise correlation between the physicochemical properties and their atomic-packing structures at an atomic-level. Herein we synthesized an Au8 cluster capped by four ferrocene ligands (DPPF), in which the ferrocene not only can direct the precise formation of the Au8 cluster, but also can solidify the structural pattern of the Au8 cluster. The Au8(DPPF)4 clusters as heterogeneous catalysts can achieve efficiently catalytic performances for the CO oxidation reaction, mainly due to the resistance to aggregation into large particles under reaction conditions. Our results suggest that the homolytic phosphine dissociation nature and the postdissociation reconstruction effect induced by Fe may enhance the catalytic performances of Au8(DPPF)4.

Efficiently capturing tobacco specific nitrosamines with Hß zeolite in solution.

The high-efficiency capture of Tobacco Specific Nitrosamines by Hß zeolite in solution is reported for the first time, along with the adsorption of 4-methylnitrosamino-1-3-pyridyl-1-butanone in aqueous solution. Different from other zeolites such as NaZSM-5, the specific pore size of Hß exerted a crucial function endowing the zeolite a higher removal of TSNA and selectivity of NNK. The adsorption thermodynamics of NNK by Hß in aqueous adsorption was fitted to Temkin adsorption model with a linearly decreasing isosteric heat of adsorption. In addition, the adsorptive capacity of Hß zeolite for NNK reached over 70 mg g-1, offering a powerful sorbent of TSNA to protect environment.

New shape-selectivity discovered on graphene-based materials in catching tobacco specific nitrosamines.

New shape-selectivity of graphene-based materials was discovered on this article. To explore the new selectivity, the structure and surface state of graphene and carbon nanotube were examined firstly, and their specific selectivity was verified and was compared with that of ZSM-5 zeolite in aqueous solutions of tobacco specific nitrosamines (TSNA) along with dyes. These two adsorbents trapped about 55% and 70% of 4-methylnitrosamino-1-3-pyridyl-1-butanone (NNK) but only 3% of N'-nitrosonornicotine (NNN) in solution, having an obvious selectivity for the former, due to its stronger interaction with graphene. NNK on graphene sheet obtained more electrons (0.015 e) and owned larger adsorption energy (15.63 kcal mol-1) than that of NNN (0.003 e, 9.19 kcal mol-1), according to theoretical calculation and FTIR results. More 95 or 136 mg g -1 acid red 88 than methyl orange was captured by graphene or carbon nanotube, demonstrating this special and abnormal selectivity again. With new selectivity, graphene showed a higher capacity (6.9%) and shorter adorption equilibrium time (5 min) for TSNA than the typical selecive sorbent ZSM-5 zeolite (1.7% and 20 min) in tobacco solution but kept the similar selctivity to NNK, paving a new way to control the carcinogens like TSNA in environment.

Creating an Optimal Microenvironment within Mesoporous Silica MCM-41 for Capture of Tobacco-Specific Nitrosamines in Solution.

To meet the requirement of capturing tobacco-specific nitrosamines (TSNA) for environment protection, a unique microenvironment was carefully created inside the channels of mesoporous silica MCM-41. In situ carbonization of template micelles at 923 K, combined with the excess aluminum used in one-pot synthesis of MCM-41, is adopted to tailor the tortuosity of mecsoporous channels, while loaded metal oxides (5 wt %) and the Al component in the framework are employed to exert the necessary electrostatic interaction toward the target carcinogens TSNA in solution. The elaborated microenvironment created in mesoporous sorbents was characterized with XRD, N2 adsorption-desorption, TEM, XPS, and TG-DSC methods. Various solutions of Burley- and Virginia-type tobaccos were used to assess the adsorption performance of new mesoporous sorbents, and the influence of the solid-to-liquid ratio, adsorption time, and loading amount of CuO on the adsorption was carefully examined. The representative sample 5%Cu/AM-10c could capture 27.2% of TSNA in Burley tobacco solution, and its capacity reached 0.3 mg g-1 in Snus tobacco extract solution, offering a promising candidate for the protection of the environment and public health.

Biosynthesis of CdS nanoparticles in banana peel extract.

Cadmium sulfide (CdS) nanoparticles (NPs) were synthesized by using banana peel extract as a convenient, non-toxic, eco-friendly 'green' capping agent. Cadmium nitrate and sodium sulfide are main reagents. A variety of CdS NPs are prepared through changing reaction conditions (banana extracts, the amount of banana peel extract, solution pH, concentration and reactive temperature). The prepared CdS colloid displays strong fluorescence spectrum. X-ray diffraction analysis demonstrates the successful formation of CdS NPs. Fourier transform infra-red (FTIR) spectrogram indicates the involvement of carboxyl, amine and hydroxyl groups in the formation of CdS NPs. Transmission electron microscope (TEM) result reveals that the average size of the NPs is around 1.48 nm.