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Abstract: Graphene hybridized with ZnO could produce an efficient photocatalyst. The ZnO nanoparticles were firstly coated with an appropriate amount of graphene oxide, the graphene oxide was then in situ reduced to form the ZnO/graphene composite. Graphene hybridized ZnO photocatalyst showed enhanced photocatalytic activity for the degradation of organic dye. The degree of photocatalytic activity enhancement strongly depended on the coverage of graphene on the surface of ZnO nanoparticles. The sample of 2wt% graphene hybridized ZnO showed the highest photocatalytic activity, which was about 4 times as that of pristine ZnO. The enhancement of photocatalytic activity was attributed to the high migration efficiency of photo-induced electrons and the inhibited charge carriers recombination due to the electronic interaction between ZnO and graphene. The electronic interaction was systematically studied and confirmed by the photoelectrochemical measurements. [ABSTRACT FROM AUTHOR]

Abstract: Highly crystalline orthorhombic Bi2MoO6 particles with high visible-light photocatalytic activity have been controllably synthesized via a facile hydrothermal process without adding any surfactant. The morphologies of Bi2MoO6 with nanosheet and microrod can be selectively obtained by adjusting the pH value of the reactant. The formation mechanisms of nanosheet and microrod structures were then discussed based on the H+ cations adsorption abilities on different crystal faces. The Bi2MoO6 samples prepared at acidic condition showed 12 times higher photocatalytic activity than that prepared at basic condition under visible-light irradiation. The reason for the big difference in the photocatalytic activities for the Bi2MoO6 samples obtained at different pH values were systematically studied based on their shape, size and the variation of local structure. [Copyright &y& Elsevier]

Abstract: La0.5Ba0.5MnO3 nanocubes and nanoparticles were synthesized by hydrothermal and co-precipitation methods, respectively. The catalytic performances and thermal stabilities of the samples in the oxidation of CO and CH4 were evaluated. La0.5Ba0.5MnO3 nanocubes showed much higher catalytic activity and thermal stability in CO and CH4 oxidation compared with the nanoparticles. After running at 560°C for 50h under the reaction conditions in CH4 oxidation, the surface area of the nanoparticles decreased significantly, while the nanocubes well maintained their surface area. Jahn–Teller effect had a significant influence on the catalytic performances of La0.5Ba0.5MnO3 nanocubes and nanoparticles. The much higher catalytic activity and thermal stability of La0.5Ba0.5MnO3 nanocubes were mainly predominated by the perfect single crystal structure. [Copyright &y& Elsevier]

Abstract: The novel hollow Mn3O4-in-Co3O4 and hollow Co3O4 microspheres were prepared through a hydrothermal route, following by subsequent impregnation and annealing. The samples were characterized by SEM (EDS), TEM (ED), XRD, and N2 adsorption. The chemiluminescence (CL) and catalytic properties for CO oxidation over these hollow samples were evaluated. The hollow Mn3O4-in-Co3O4 catalyst showed a stronger CL response to CO and a higher catalytic activity for CO oxidation, compared with the hollow Co3O4 sample, which was attributed to the novel structure of crystals-in-ball. [Copyright &y& Elsevier]

Abstract: To efficiently utilize the solar light and improve the photooxidation technique for wastewater purification, a new type of photoelectrode, visible light responsive Bi2WO6 nanoflake film, was covered onto the indium–tin oxide glass substrate via the electrostatic self-assembly deposition. The photocatalytic oxidation, electro-oxidation, and photoelectrocatalytic (PEC) oxidation of 4-chlorophenol (4-CP) in aqueous solution using the film electrode were investigated and compared under visible light irradiation (λ >400nm). The experimental results demonstrated that 4-CP could be degraded by the nanoflake film under visible light irradiation or by applying a bias potential greater than 0.8V. Based on X-ray photoelectron spectra (XPS) analysis of the electrode after electrochemical reaction, the electropolymerization was suggested to occur in the electro-oxidation process. Furthermore, degradation efficiency of 4-CP was largely increased by combined electro-oxidation and photocatalysis. And, it is the largest at the bias potential of 2.0V. The characteristics of the PEC degradation of 4-CP were also investigated by electrochemical impedance spectroscopy (EIS). It is shown from the EIS that the PEC degradation appears to be a simple reaction on the electrode surface, suggesting that only one step of charge transfer is involved in the electrode process. The total organic carbon analysis indicated that 4-CP could be efficiently mineralized during the PEC process. [Copyright &y& Elsevier]

Abstract: An efficient TiO2 photocatalyst was obtained by surface hybridization with a thin layer of C60 molecules. The photocatalytic performance of C60-hybridized TiO2 under ultraviolet light irradiation was enhanced by 4 times compared with that of P25-TiO2 photocatalyst. The enhanced photocatalytic activity for C60-hybridized TiO2 was originated from the high migration efficiency of photo-induced electrons on the interface of C60 and TiO2, which was produced by the interaction TiO2 and C60 with a conjugative π-system. The interaction was confirmed by the Raman spectroscopy, infrared spectroscopy and photoelectrochemical measurements. The enhancement of photocatalytic activity strongly depended on the coverage of C60 molecules on the surface of TiO2, and the optimum hybridization effect was found at a weight ratio of 2.5wt% (C60/TiO2). The mechanism for the enhanced photocatalytic activity of TiO2 by C60 was discussed. [ABSTRACT FROM AUTHOR]

The carbon nanotubes (CNTs) have been combined with graphitic carbon nitride (g-C 3 N 4 ) through the amidation reaction. The hybrid catalyst of g-C 3 N 4 -CNTs with well-defined and stable structure exhibits efficient catalytic performance (32.6 μmol h −1 ) for photocatalytic H 2 O 2 production in the presence of formic acid under visible light. The value of electron transfer during the oxygen reduction reaction (ORR) process obtained from the Koutecky-Levich plot for g-C 3 N 4 -CNTs (n = 1.96) is higher than that for g-C 3 N 4 (n = 1.29), suggesting that the CNTs covalent combined with g-C 3 N 4 can promote the electrons generation. The p -benzoquinone (PBQ) scavenger experiments, the electron spin resonance (ESR) signal and quantitative experiment of O 2 − results reveal that the negative shifts of the conduction band (CB) level from g-C 3 N 4 to g-C 3 N 4 -CNTs can enhance the single-electron reduction of O 2 to O 2 − and further promote the sequential two-step single-electron O 2 reduction reaction to H 2 O 2 . [ABSTRACT FROM AUTHOR]

Tobacco-specific N -nitrosamines (TSNAs) are strong carcinogens widely found in tobacco products, environmental tobacco smoke, lake, and wastewater. The main objective of this study was to investigate the effects of cigarette smoke with different yields of TSNAs (NNK, NNN, NAT, NAB) and nicotine on the levels of biomarkers of exposure in smokers' plasma. Three hundred healthy volunteers were recruited comprising 60 smokers of each of 3 mg, 8 mg and 10 mg ISO tar yield cigarettes and 60 smokers who smoked 10 mg, 8 mg, and 3 mg for 14 days sequentially and 60 non-smokers. All study participants were male, aged from 21 to 45 years old, and were recruited from a same unit in Hebei, China. We measured the levels of NNAL, NAT, NNN, NAB and cotinine in plasma from 240 smokers and 60 non-smokers using a novel method established by online two-dimensional solid phase extraction-liquid chromatography-tandem mass spectrometry. The results showed that NNAL, NAT, NNN, NAB and cotinine in the plasma of smokers smoking cigarette with low TSNAs and nicotine were lower than that with high TSNAs and nicotine. When smokers switched from higher to lower TSNA yields of cigarettes, their plasma NNAL, NAT, NNN, NAB levels significantly decreased. The plasma concentrations of NNAL were significantly correlated with those of cotinine, NNN, NAT and NAB for smokers (p < 0.001). Similarly, the plasma concentrations of cotinine were significantly correlated with those of NNN, NAT and NAB for smokers (p < 0.001). The plasma NNAL, NAT, NNN, NAB and cotinine levels for smokers were significantly higher than those for non-smokers. These findings suggested that the total NNAL, NNN, NAT, NAB and cotinine in plasma were valid and reliable biomarkers for human exposure to TSNAs and nicotine. • The plasma levels of TSNAs in smokers and non-smokers were measured. • The variations of plasma TSNAs of smokers after switching were investigated. • The reductions in smoke TSNA yields can reduce mean biomarkers of exposure levels. • TSNAs and nicotine metabolite biomarkers in plasma were highly correlated. • The plasma TSNA were valid and reliable biomarkers of human exposure to TSNAs. [ABSTRACT FROM AUTHOR]

Tobacco-specific N -nitrosamines (TSNAs) are strong carcinogens widely found in tobacco products, environmental tobacco smoke, lake, and wastewater. The main objective of this study was to investigate the effects of cigarette smoke with different yields of TSNAs (NNK, NNN, NAT, NAB) and nicotine on the levels of biomarkers of exposure in smokers' plasma. Three hundred healthy volunteers were recruited comprising 60 smokers of each of 3 mg, 8 mg and 10 mg ISO tar yield cigarettes and 60 smokers who smoked 10 mg, 8 mg, and 3 mg for 14 days sequentially and 60 non-smokers. All study participants were male, aged from 21 to 45 years old, and were recruited from a same unit in Hebei, China. We measured the levels of NNAL, NAT, NNN, NAB and cotinine in plasma from 240 smokers and 60 non-smokers using a novel method established by online two-dimensional solid phase extraction-liquid chromatography-tandem mass spectrometry. The results showed that NNAL, NAT, NNN, NAB and cotinine in the plasma of smokers smoking cigarette with low TSNAs and nicotine were lower than that with high TSNAs and nicotine. When smokers switched from higher to lower TSNA yields of cigarettes, their plasma NNAL, NAT, NNN, NAB levels significantly decreased. The plasma concentrations of NNAL were significantly correlated with those of cotinine, NNN, NAT and NAB for smokers (p < 0.001). Similarly, the plasma concentrations of cotinine were significantly correlated with those of NNN, NAT and NAB for smokers (p < 0.001). The plasma NNAL, NAT, NNN, NAB and cotinine levels for smokers were significantly higher than those for non-smokers. These findings suggested that the total NNAL, NNN, NAT, NAB and cotinine in plasma were valid and reliable biomarkers for human exposure to TSNAs and nicotine. • The plasma levels of TSNAs in smokers and non-smokers were measured. • The variations of plasma TSNAs of smokers after switching were investigated. • The reductions in smoke TSNA yields can reduce mean biomarkers of exposure levels. • TSNAs and nicotine metabolite biomarkers in plasma were highly correlated. • The plasma TSNA were valid and reliable biomarkers of human exposure to TSNAs. [ABSTRACT FROM AUTHOR]

Abstract: In this work, the LiFePO4 nanorods are synthesized in an ionic liquid (IL) in the presence of a surfactant. The samples are characterized by X-ray diffraction, scanning electron microscopy, high resolution transmission electron microscopy, electron diffraction and nitrogen adsorption. The as-obtained LiFePO4 nanorods in the IL have the diameter of about 200nm and the length of 1–2μm; but the aggregated LiFePO4 microparticles are obtained in the aqueous solution. The results show that a higher temperature and a longer duration are needed in the IL than in the aqueous solution for the formation of LiFePO4; that both IL and the surfactant play the key roles in the formation of LiFePO4 nanorods. Furthermore, their charge and discharge properties are investigated. The LiFePO4 nanorods show a higher discharge capacity (150 at 1C rate) and a higher rate capability than the aggregated particles (133mAhg−1). The adopted IL approach may provide a “green” route to achieve excellent battery materials. [Copyright &y& Elsevier]

Abstract: The highly porous Co3O4 nanorods are prepared by a simple hydrothermal method, in which CO(NH2)2 is employed as precipitating agent, and K60 (PVP, polyvinylpyrrolidone) is used as surfactant to improve the stability of the nanoparticles. For comparison, the bulk Co3O4 is prepared by thermal decomposition of cobalt nitrate. The samples are characterized by field emission scanning electron microscopy (FE-SEM), energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), selected area electron diffraction (ED), X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, N2 adsorption, Thermogravimetric analysis (TG), H2-temperature programmed reduction (TPR), CO-, CH4-, and O2-temperature programmed desorption (TPD). The catalluminescence (CTL) and catalytic properties of the samples are investigated extensively. The results show that the Co3O4 nanorods are composed of nanoparticles, and have a large number of pores with a narrow pore size distribution (1.5–7nm). Compared with the bulk Co3O4, the porous nanorods have a higher CTL intensity of CO oxidation, and a higher activity of CH4 combustion especially at a higher gas hourly space velocity (GHSV), which has been ascribed to its porous structure and larger surface area. [Copyright &y& Elsevier]