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Abstract: Bismuth titanates (BTs) can be fabricated by electrospinning combined with calcination at different temperatures. BiOCl/Bi2Ti2O7 nanorod heterostructures were obtained at 500 °C. They possess excellent photocatalytic efficiency and stability for tetracycline hydrochloride (TC‐HCl) degradation under simulated solar light. The excellent catalytic activity is predominantly attributed to the heterostructure between BiOCl and Bi2Ti2O7, which accelerates the separation of photogenerated carriers while the narrow band gap of Bi2Ti2O7 enhances solar energy utilization. On the basis of energy band engineering, scavenger tests, and LC‐HRMS analysis, a possible degradation pathway of TC‐HCl and photocatalytic mechanism were proposed. Our work can predict a facile route for achieving high photocatalytic performance of Bi2Ti2O7‐based materials in the application of TC‐HCl degradation. [ABSTRACT FROM AUTHOR]

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]

Nitrogen and carbon co-doped porous TiO2 nanofibers (NCPTNs) were exploited by a combination of electrospinning and controlled calcination technologies. Polyvinyl pyrrolidone (PVP) was employed both as a template and as a nitrogen and carbon source. It is clear that the prepared NCPTNs exhibit high absorption in the visible light region, suggesting that the co-doping of nitrogen and carbon onto TiO2 not only leads to a shift of the absorption edge to lower energy by inducing new band levels, but also creates large amounts of single-electron-trapped oxygen vacancy. Besides, the porous structure and high surface area provide large active points for the photodecomposition reaction of methylene blue. Moreover, the NCPTN obtained in 5 wt% urea shows the highest photocatalytic activity for methylene blue decomposition under the visible light irradiation. [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]

[Display omitted] • Novel LaCoO 3 was obtained by SBA-15 assisted electrospinning combined with etching. • LaCoO 3 are confined in nanorods or scattered on mesopores/surface of SBA-15. • Deactivation by water vapor is reversible. • Reducibility, O ads /O latt , Co2+/Co3+, and exposed surface Co are important. A high surface area rhombohedral LaCoO 3 perovskite (ELS-JX) was synthesized by SBA-15 assisted electrospinning combined with NaOH etching technology, and investigated for total benzene oxidation. LaCoO 3 nanoparticles are confined in the self-assembled nanorods or scattered on the mesopores/surface of SBA-15, resulting in less aggregation of perovskite nanoparticles for ELS-JX. H 2 -TPR analysis and XPS measurements reveal that better low-temperature reducibility, higher O ads /O latt and Co2+/Co3+ as well as larger amounts of surface exposed Co species of ELS-JX considerably enhance its catalytic activity for total benzene oxidation compared to sol-gel (SG) and SBA-15 free electrospinning (EL) method synthesized LaCoO 3. Moreover, the results of O 2 -TPSR match well with the catalytic performances of SG, EL and ELS-JX. In addition, the presence of water vapor has a negative effect on benzene oxidation over the best performed ELS-JX. [ABSTRACT FROM AUTHOR]

Abstract: PVC-based carbon nanofibers with graphitic nanoparticles were fabricated by an electrospinning–carbonization technique and characterized by SEM, (HR)TEM and XRD. The hydrogen storage capability of the resultant nanofibers was evaluated using the volumetric method. The results show that the PVC-based carbon nanofibers obtained from the electrospun PVC/NiCl2 nanofibers consist of both amorphous carbon and a well-grown graphite layered sphere with a diameter of 35nm. It is clear that the iodine treatment is essential for retaining a fibrous shape during the carbonization, and Ni is beneficial to the growth of graphitization at low temperatures. The hydrogen storage capacity of the PVC-based carbon nanofibers obtained at 1000°C is 0.30wt%, suggesting that the resultant nanofibers are a potential energy storage material. [Copyright &y& Elsevier]

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]

Abstract: An electrospinning–calcination strategy was established to fabricate Y2O3 nanofibers doped with rare earth ions (Tb, Sm and Dy) using electrospun PVA/RE(NO3) x /Y(NO3)3 composite nanofibers as precursors (x=3.4). The prepared nanofibers were characterized by XRD, FESEM, EDS, (HR)TEM and PL analyses. Based on the experimental results, a solid–solid growth mechanism (SS) was proposed to describe the formation of inorganic crystalline fibers from organic/inorganic composite nanofibers by calcination. It was determined that carbonaceous nanoparticles that were formed in the process of pre-carbonization adsorbed Y2O3:RE nanoparticles to grow Y2O3:RE crystal, and the resultant nanofibers exhibited a typical crystalline domain with grain boundary. The obtained Y2O3:RE nanofibers possessed excellent luminescent characteristics and could be used as an appreciable luminescent material. [Copyright &y& Elsevier]

A one-dimensional (1D) core-shell of Co-Ce oxide has been prepared by multifluidic coaxial electrospinning method and evaluated for the total oxidation of propane (C 3 H 8). Activity and morphological characterizations show that the CeO 2 @Co 3 O 4 nanofiber catalyst, of which the core is CeO 2 and the shell is Co 3 O 4 , exhibits excellent oxidation activity. The exposed Co 3 O 4 grown on the outside of the fibers can rapidly react with C 3 H 8 while CeO 2 with high oxygen storage capacity in the inside is conductive to the enhanced oxidation rate. Besides, the continuous grain boundary provides a fast mass transfer channel for lattice oxygen, and rich oxygen vacancies favor the mobility of active oxygen species. In situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTs) confirms that the CeO 2 @Co 3 O 4 catalyst have a faster rate of C 3 H 8 adsorption and better oxidation activity with respect to the counterpart using a single-needle electrospinning method. Moreover, the CeO 2 @Co 3 O 4 catalyst displays excellent thermal stability, and strong resistance against 5 vol% H 2 O and 5 vol% CO 2 at both 300 and 400 °C. Our strategy can give some new insights into morphological engineering to promote active oxygen mobility via the construction of one-dimensional core-shell of metal oxides for catalytic oxidation of VOCs. ga1 • CeO 2 @Co 3 O 4 nanofibers were prepared by multifluidic coaxial electrospinning. • Co 3 O 4 shell rapidly reacts with C 3 H 8 while CeO 2 core enhances oxygen migration. • Continuous grain boundary provides a fast mass transfer channel for lattice oxygen. • Abundant oxygen vacancies favor the mobility of active lattice oxygen. • Superior oxidation activity, thermal stability and H 2 O/CO 2 resistance were obtained. [ABSTRACT FROM AUTHOR]