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The color-tunable fluorescent LaOCl:Eu, Ce nanofibers were successfully fabricated via an electrospinning combined with calcination route, in which PVA was employed as a template. XRD, TG-DTG results show that the heat-treatment of the nanofibers at 750 °C is enough to obtain highly crystallized LaOCl:Eu, Ce samples. Scanning electron microscopy analysis indicates that LaOCl:Eu, Ce nanofibers are composed of wafer nanograins with mean diameter of ~30 nm. Photoluminescence analysis shows that the luminescence intensity has changed with the varying Ce doping content in LaOCl:Eu nanofibers. Additionally, CIE chromaticity coordinates of LaOCl:5% Eu, x% Ce nanofibers change from orange light region of (0.4997, 0.4828) and (0.5232, 0.4627) at x = 5.0 and 2.5 to red light region of (0.5661, 0.4251) at x = 1.7, then to orange light region of (0.5590, 0.4318) at x = 1.0, respectively. Hence the fluorescence color of LaOCl:Eu, Ce nanofibers can be tuned by simply adjusting the Eu/Ce ratio, which is a promising candidate for application in LEDs. [ABSTRACT FROM AUTHOR]

Ag/AgCl composite as an alternative visible-light photocatalyst has attracted extensive interests; however, the high charge carrier recombination rate and short-term photocatalytic durability limit their practical application. In the present work, TiO 2 hollow nanofibers (ELTiO 2 ) grafted Ag/AgCl is fabricated via electrospinning-precipitation method. Compared with Ag/AgCl and Ag/AgCl-SGTiO 2 (sol-gel synthetized TiO 2 ), 2.89 and 1.59-fold enhancement in the photodegradation rate toward MO is observed over Ag/AgCl-ELTiO 2 under visible light irradiation. The enhancement of photocatalytic activity is mainly attributed to the higher content of the exposed AgCl {1 1 1} facet, which is beneficial for the separation of photogenerated carriers and accounts for more active sites. Moreover, Ag/AgCl-ELTiO 2 shows better photostability than bare Ag/AgCl. [ABSTRACT FROM AUTHOR]

Abstract: Electrospun nanofibers of poly (vinyl alcohol) (PVA)/Lanthanum (Ш) chloride (LaCl3) composite were employed to prepare the LaOCl nanofibers by calcination. TG-DSC was used to investigate the thermal property of precursor, while FT-IR, XRD, FESEM and TPD were employed to characterize the derived LaOCl nanofibers. Results indicate that the addition of LaCl3 leads to the formation of fork segments in the structure of electrospun PVA/LaCl3 composite nanofibers, therefore, changing the decomposition behavior of the fibers. Pure LaOCl fibers with a diameter range of 90–220nm can be obtained by calcination of electrospun PVA/LaCl3 composite nanofibers at 700°C for 7h. The resultant LaOCl nanofibers show a good sensing behavior for CO2 gas. [Copyright &y& Elsevier]

BACKGROUND: Electrospinning is a highly effective method in order to generate nano-scaled fibers. In conventional electrospinning technique, geometry of nanofibers are mostly random due to the chaotic behavior of polymer jet. OBJECTIVE: Purpose of this study is to produce aligned nanofibers from PVP polymers with advanced electrospinning technique in order to be used in a potential novel sensor applications, tissue regeneration and engineering. METHODS: In this study, by using finite hollow cylinder focusing electrodes, an external electrostatic field is created. With these electrodes, it is aimed to decrease whipping instability of polymer jet. In addition, it is also investigated that the alignment ratio of nanofibers by using conductive parallel electrodes which placed through jet trajectory. RESULTS: In conclusion, with the effect of electrical field created by cylinder electrodes, radius of the fiber dispersion on the collector was able to be reduced and aligned nanofibers were successfully produced by using electrical field generated from the parallel plates. CONCLUSIONS: Radius of the fiber dispersion on the collector is 9.95 mm and fiber diameters varied between 800 nm and 3 μm. Additionally, alignment ratio of the fibers is determined with ImageJ software. These alignment of nanofibers can be used in tissue engineering applications and sensor applications. [ABSTRACT FROM AUTHOR]

Abstract: La(III)-doped ZnO/C nanofibers with core–shell structure were prepared by calcination of electrospun PAN(polyacrylonitrile)/La(NO3)3/Zn(Ac)2 composite nanofibers and characterized by XRD, FESEM, (HR)TEM, and EDS respectively. The photocatalytic activity of La(III)-doped ZnO/C nanofibers in the decomposition of RhB under UV–lamp light irradiation was also investigated. The results show that the prepared composite fibers possess a rough surface and flower-like morphology with diameters from 50 to 100nm and exhibit high photocatalytic activity in the decomposition of RhB solution. It is also found that the La(III) doping concentration plays an important role in photocatalytic performance during the degradation reaction of RhB. 2% La(III) is suggested to be the optimum doping dosage. [Copyright &y& Elsevier]

Abstract: Ag/TiO2 nanofibers heterostructure were fabricated by calcination of electrospun PVP/Ti(OiPr)4/AgNO3 composite nanofibers and characterized by XRD, FESEM, EDS, and (HR)TEM. The photocatalytic activity of Ag/TiO2 in the decomposition of parathion was also investigated. It was found that the prepared heterostructure composite included Ag nanoparticles distributed uniformly in the TiO2 nanofibers. Comparing with pure TiO2 nanofibers and Ag nanofibers, Ag/TiO2 heterostructure photocatalyst exhibited enhanced photocatalytic activity under ultraviolet light irradiation in the decomposition of parathion aqueous solution. The content of Ag nanoparticles on TiO2 nanofibers played an important role in photocatalytic performance during the parathion degradation reaction. 4% Ag was found to be the optimum doping dosage. [Copyright &y& Elsevier]