Publications by authors named "Xiangting Dong"

42 Publications

Novel photosensitive dual-anisotropic conductive Janus film endued with magnetic-luminescent properties and derivative 3D structures.

J Colloid Interface Sci 2021 May 26;601:899-914. Epub 2021 May 26.

Key Laboratory of Applied Chemistry and Nanotechnology at Universities of Jilin Province, Changchun University of Science and Technology, Changchun 130022, China.

A new photosensitive dual-anisotropic conductive Janus film (PDCJF) is proposed for the first time. It is rationally designed and manufactured by facile electrospinning. PDCJF is firstly constructed using 2,7-dibromo-9-fluorenone (DBF) with photoconductive and luminescent properties. Janus nanofibers are respectively used as the building units to construct the top layer (T-PDCJF) and the bottom layer (B-PDCJF) of PDCJF. The two layers are tightly bonded to form PDCJF. Under light irradiation, there is photosensitive dual-anisotropic conduction in PDCJF, but there is no anisotropic conduction without light. Thus, the transition of PDCJF from mono-functional magnetism to tri-functionalities is realized under light and without light. The luminescence color of PDCJF is tunable and it emits white-light. This is made possible by modulating the amounts of luminescent substances and excitation wavelength. The microscopic Janus nanofibers used as building units and macroscopic Janus film structure ensure high photosensitive dual-anisotropic conduction and excellent fluorescence in PDCJF. The two-dimensional (2D) PDCJF is rolled to obtain three-dimensional (3D) Janus-type tubes and 2D plus 3D complete flag-like structures with exceptional multi-functionalities. The new findings can strongly guide in developing advanced multi-functional nanostructures.
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http://dx.doi.org/10.1016/j.jcis.2021.05.141DOI Listing
May 2021

Local structure modulation of Mn-doped NaSiGeF red phosphors for enhancement of emission intensity, moisture resistance, thermal stability and application in warm pc-WLEDs.

Dalton Trans 2020 Oct;49(39):13805-13817

Key Laboratory of Applied Chemistry and Nanotechnology at Universities of Jilin Province, Changchun University of Science and Technology, Changchun 130022, P. R. China.

Nowadays, the development of Mn4+-activated fluoride phosphors with efficient water and thermal stabilities continues to pose a huge challenge with regard to prolonging the service life and stabilizing the light output for phosphor-converted white light-emitting diodes (pc-WLEDs). Therefore, the synthesis strategy of simple crystal structure optimization is proposed to realize simultaneously the high hydrophobic and thermal stabilities of fluoride phosphors. Herein, Mn4+-doped Na2Si1-yGeyF6 red phosphors are successfully synthesized by a simple coprecipitation method. Satisfactorily, the optimization of Ge4+ and Mn4+ concentrations successfully enhances the luminescence intensity of the original phosphor (Na2SiF6:Mn4+) and an obvious red shift can be found. Moreover, the CIE coordinates of red light show that the phosphor has low correlated color temperature and excellent color purity. Based on excitation and emission spectra, the crystal field strength (Dq), Racah parameters (B and C) and nephelauxetic ratio (β1) show that a new Na2Si0.5Ge0.5F6 matrix can meet the high requirements of the crystal field environment when Mn4+ becomes the fluorescence center. Interestingly, the local structure modulation stabilizes the state of existence of Mn4+ in the matrix and enhances the moisture resistance of the phosphor. In addition, the as-prepared Na2Si0.5Ge0.5F6:Mn4+ phosphor possesses admirable thermal quenching behavior and color stability at high temperature. More importantly, low correlated color temperature (3408 K), high color rendering index (89.4) and preeminent luminous efficiency (112.89 Im W-1) are achieved using the YAG:Ce3+-Na2Si0.5Ge0.5F6:0.06Mn4+ system as color converters for warm pc-WLEDs. The work provides a new insight into the construction of red phosphors with favorable water and thermal stabilities for warm pc-WLEDs.
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http://dx.doi.org/10.1039/d0dt02935aDOI Listing
October 2020

A nanostructured MoO/MoS/MoP heterojunction electrocatalyst for the hydrogen evolution reaction.

Nanotechnology 2020 May 14;31(22):225403. Epub 2020 Feb 14.

Changchun University of Science and Technology Key Laboratory of Applied Chemistry and Nanotechnology, Changchun, 130022, People's Republic of China.

Electrocatalytic production of hydrogen from water is considered to be a promising and sustainable strategy. In this work, the low-cost nanostructured MoO/MoS/MoP heterojunction is successfully synthesized by phosphorization of the pre-prepared urchin-like MoO/MoS nanospheres as the stable, highly efficient electrocatalysis for the hydrogen evolution reaction (HER). The MoO/MoS/MoP-800 (MoO/MoS nanospheres are phosphated at 800 °C) displays a catalytic ability for the HER with an overpotential of 135 mV to achieve 10 mA cm and a Tafel slope of 67 mV dec in 0.5 M HSO, which is superior to MoO/MoS nanospheres (200 °C; 24 h), MoO/MoS/MoP-700 (MoO/MoS nanospheres are phosphated at 700 °C) and MoO/MoS/MoP-900 (MoO/MoS nanospheres are phosphated at 900 °C). Meanwhile, the catalyst exhibits superior properties for HER with an overpotential of 145 mV to achieve 10 mA cm and a Tafel slope of 71 mV dec in 1 M KOH solution. Detailed characterizations reveal that the improved HER performances are significantly related to P-doping and the spherical nanostructure. This work not only provides a low-cost selective for electrocatalytic production of hydrogen, but also serves as a guide to optimize the composition and structure of nanocomposites.
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http://dx.doi.org/10.1088/1361-6528/ab767aDOI Listing
May 2020

One-step hydrothermal synthesis of Ni-Co sulfide on Ni foam as a binder-free electrode for lithium-sulfur batteries.

J Colloid Interface Sci 2020 Apr 26;565:378-387. Epub 2019 Dec 26.

School of Chemistry and Environmental Engineering, Changchun University of Science and Technology, Changchun 130022, PR China. Electronic address:

NiCoS, CoS/NiS and Ni-Co sulfide grown on Ni-foam were successfully synthesized with a simple one-step hydrothermal method via adjusting the mass fraction of cobalt and sulphur source, forming a free-standing advanced hybrid electrode for Li-S battery. Interestingly, compared with typical synthesis methods of Ni-Co sulfide, this new synthetic method supplies nickel source through Ni-foam rather than soluble inorganic salt and avoid destroying the original structure in the process of secondary hydrothermal reaction. With the integrity of the whole mechanical structure of the hosts, the hybrid electrode behave strong chemical bonding for polysulfides and superior electrocatalytic activity for accelerating the polysulfides redox reactions. The results revealed that foam-like structure of S/[email protected] sulfide (S/[email protected]) electrode delivers the highest capacity of 1352.36 mAh g at 1 C after 10 cycles and the initial capacity of S/[email protected] electrode is 1920.28 mAh g at 0.1 C. The results offer a facile and promising engineering strategy to achieve high sulfur utilization.
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http://dx.doi.org/10.1016/j.jcis.2019.12.112DOI Listing
April 2020

Synthesis of multifunctional rare-earth fluoride/Ag nanowire nanocomposite for efficient therapy of cancer.

Mater Sci Eng C Mater Biol Appl 2019 Nov 3;104:109940. Epub 2019 Jul 3.

Key Laboratory of Applied Chemistry and Nanotechnology at Universities of Jilin Province, Changchun University of Science and Technology, Changchun 130022, PR China. Electronic address:

Well-dispersed Ag nanowires and PVP-modified BaGdF: Yb, Er spherical nanoparticles were prepared by simple solvothermal and hydrothermal method, and they were further combined to obtain photo-thermal-magnetic multifunctional Ag/BaGdF: Yb, Er nanocomposites. Under NIR laser irradiation, monodispersed rare-earth fluoride BaGdF: Yb, Er in nanocomposite exhibit good upconversion fluorescent. Meanwhile, under the action of an external magnetic field, the nanocomposite also exhibits good magnetic properties and excellent contrast efficiency by CT/MR imaging. The NCs possess good structure and photothermal stability at multiple cycles due to that Ag nanowires are modified by polyvinyl pyrrolidone and sodium citrate. The biocompatibility and low toxicity of NCs are also remarkable. Importantly, the unique linear morphology of Ag particles can achieve high efficiency conversion between light and heat. Furthermore, in vitro tests also confirm the high efficiency of photothermal therapy for cancer cells.
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http://dx.doi.org/10.1016/j.msec.2019.109940DOI Listing
November 2019

Utilizing modules of different functions to construct a Janus-type membrane and derivative 3D Janus-type tube displaying synchronous trifunction of conductive aeolotropism, magnetism and luminescence.

Nanotechnology 2019 Oct;30(43):435602

Key Laboratory of Applied Chemistry and Nanotechnology at Universities of Jilin Province, Changchun University of Science and Technology, 130022 Changchun, People's Republic of China.

The microstructures and macrostructures play a crucial role in the properties and applications of multifunctional materials. Herein, microscopic partition and macroscopic partition are combined by devising and preparing different modules that can be elaborately devised to possess specific performances. A two-dimensional (2D) 3-module Janus-type membrane multifunctionalized by conductive aeolotropism, magnetism and luminescence (defined as 3M-CML Janus-type membrane) is constructed via electro-spinning. The modular structure of 3M-CML Janus-type membrane is obtained by devising and constructing three different modules, including luminescence module (denoted as L module), conductive aeolotropism-luminescence module (marked as C-L module) and magnetism-luminescence module (named as M-L module). The results prove that almost no mutual detrimental influences exist among different modules owing to the macroscopic modular structure and Janus-type structure, which effectively avoids the negative interactions among different materials. Tb(BA)phen/PVP nanofiber, [PMMA/Eu(BA)phen]//[PMMA/PANI] Janus-type nanoribbon and [PMMA/Tb(BA)phen]//[PMMA/FeO] Janus-type nanoribbon are, respectively, selected as building units of the three modules, which further prevents the negative interactions among different materials and improves the versatility of 3M-CML Janus-type membrane. The luminescence, adjustable conductive aeolotropism and variable magnetism of 3M-CML Janus-type membrane are systematically discussed. Meanwhile, novel flexible four types of brand-new three-dimensional (3D) Janus-type tubes are obtained by rolling modularly devised 2D 3M-CML Janus-type membrane with different rolling schemes. As derivatives of the 2D 3M-CML Janus-type membranes, macroscopic 3D Janus-types tubes exhibit similar performances to 2D 3M-CML Janus-type membranes. The 2D Janus-type membrane and 3D Janus-type tube will have momentous applications in flexible electronics and nanodevices in the future.
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http://dx.doi.org/10.1088/1361-6528/ab3386DOI Listing
October 2019

Extremely sensitive and accurate HS sensor at room temperature fabricated with In-doped CoO porous nanosheets.

Dalton Trans 2019 Jun 8;48(22):7720-7727. Epub 2019 May 8.

Key Laboratory of Applied Chemistry and Nanotechnology at Universities of Jilin Province, Changchun University of Science and Technology, Changchun 130022, China.

A facile hydrothermal method to prepare In-doped CoO porous nanosheets is reported in this paper for the first time. The prepared samples were made into gas sensors, and their sensing properties, such as response, response time, recovery time, selectivity and stability, have been researched systematically. These results indicate that the sensor fabricated with 1.0 at% In-doped CoO porous nanosheets shows a high response of 6.81 to 50 ppm and an obvious response of 1.4 to 1 ppm HS. What's more, this sensor exhibited a high selectivity and outstanding long-term stability toward HS. The excellent gas sensing performance was mainly ascribed to two reasons. (i) Doping with In increases the concentration of charge carriers, oxygen-deficient regions and the chemisorbed oxygen, which enhances the gas response. (ii) The rough porous structure is conducive to gas adsorption and capture, and provides many active sites for the sensing reaction. Therefore, 1.0 at% In-doped CoO porous nanosheets could be used as a sensing material in future applications.
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http://dx.doi.org/10.1039/c9dt01043bDOI Listing
June 2019

Novel polygonal structure Mn activated In-based Elpasolite-type hexafluorides red phosphor for warm white light-emitting diodes (WLEDs).

Dalton Trans 2019 Jan;48(4):1376-1385

Key Laboratory of Applied Chemistry and Nanotechnology at Universities of Jilin Province, Changchun University of Science and Technology, Changchun, P. R. China.

A novel type polygonal structure red emission Elpasolite-type hexafluorides (NH4)2NaInF6:Mn4+ phosphor is successfully synthesized by hydrothermal and coprecipitation methods. The samples exhibit two typical absorption bands located at the ultraviolet-visible (369 nm) and the blue light area (470 nm) and emit bright red light centered at 633 nm with high color purity. Powder X-ray diffraction (XRD) has been used to demonstrate the phase purity and crystal structure of the samples synthesized. The corresponding surface morphology and composition have been confirmed via scanning electron microscope (SEM) with an attached energy-dispersive X-ray spectrometer (EDS), respectively. All luminescence properties have been deeply investigated by excitation spectra, emission spectra, luminescence decay curves and temperature-dependent luminescent spectra. The morphology of the as-prepared phosphor is successfully controlled by adjusting reaction solvents and adding different surfactants. In addition, the optical behaviours of the red phosphors are evidently relied on the experimental procedure, the concentrations of the K2MnF6, different surfactants and reaction solvents. Concentration and thermal quenching mechanisms are discussed according to detailed experimental results. A warm white light-emitting diode (WLED) with the as-obtained red phosphor (NH4)2NaInF6:Mn4+ has been successfully produced, which has low CCT (3960 K), high CIR (Ra = 85.5) and LE of 129 lm W-1. Above results reveal the extraordinary application value of (NH4)2NaInF6:Mn4+ red phosphor for highly efficient warm WLEDs.
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http://dx.doi.org/10.1039/c8dt04690eDOI Listing
January 2019

Controlled Morphology, Improved Photoluminescent Properties, and Application of an Efficient Non-rare Earth Deep Red-Emitting Phosphor.

Inorg Chem 2018 Aug 3;57(16):9892-9901. Epub 2018 Aug 3.

Key Laboratory of Applied Chemistry and Nanotechnology at Universities of Jilin Province , Changchun University of Science and Technology , Changchun 130022 , P. R. China.

Transition-metal tetravalent manganese ions (Mn) as luminescence center of red phosphors have drawn much attention owing to their broad-band absorption extended from UV to blue regions and narrow red-emissive band. In the present work, a series of Mn-doped BaGeF red phosphors were obtained via hydrothermal method. X-ray powder diffraction, energy-dispersive X-ray spectrometer, scanning electron microscope, and photoluminescence spectra were employed to determine the crystal structure, composition, morphology, and photoluminescence properties of all samples. The prepared BaGeF:Mn samples demonstrate two dominant broadband absorption at near-UV (∼366 nm) and blue regions (∼470 nm) and intense red emissions (∼635 nm) under 470 nm excitation. In addition, the morphology and the emission intensities were successfully controlled by adjusting doping concentrations, reaction times, reaction temperatures, barium sources, and surfactants. Concentration quenching and thermal quenching mechanisms were studied in detail. When the BaGeF:Mn red phosphor was introduced into the light-emitting diode, warm white light-emitting diodes (w-LEDs) were successfully fabricated, which have high color rendering index (Ra = 86.3) and low correlated color temperature (4766 K), indicating that the BaGeF:Mn red phosphor provides a good opportunity for application in w-LEDs.
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http://dx.doi.org/10.1021/acs.inorgchem.8b00944DOI Listing
August 2018

Up/down conversion luminescence and energy transfer of Er/Tb activated NaGd(WO) green emitting phosphors.

Spectrochim Acta A Mol Biomol Spectrosc 2018 Aug 22;201:88-97. Epub 2018 Apr 22.

Key laboratory of Applied Chemistry and Nanotechnology at University of Jilin Province, Changchun University of Science and Technology, Changchun 130022, China.

A series of double scheelite-type tungstate green phosphors NaGd(WO):Er, Tb were synthesized by a hydrothermal route and subsequent calcination process, and they were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), energy-dispersive X-ray spectrometry (EDS), photoluminescence spectroscopy and fluorescence lifetime measurements. The phosphors take on octahedral microcrystals with a mean side length of ~2 μm. In the single doped phosphors system, the energy transfer processes from WO to Er or Tb were discussed. The quenching concentrations of Er and Tb are 0.05 and 0.07, respectively. The critical distances for Er and Tb ions are calculated to be 14.28 Å and 12.76 Å, respectively. When doping Er/Tb is applied in the single compound, the concentration quenching effect of Tb ions occurs via a resonant-type dipole-dipole interaction as well as that of Er ions. Under the excitation with ultraviolet (378 nm) or infrared (980 nm) light, the Er/Tb co-doped NaGd(WO) phosphors emit strong green emission. The obtained samples with bright emission intensity and appropriate decay time are suitable for use as green phosphors in the near ultraviolet LEDs and bioimaging applications.
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http://dx.doi.org/10.1016/j.saa.2018.04.041DOI Listing
August 2018

Peculiarly Structured Janus Nanofibers Display Synchronous and Tuned Trifunctionality of Enhanced Luminescence, Electrical Conduction, and Superparamagnetism.

Chempluschem 2018 Mar;83(3):108-116

Changchun University of Science and Technology, Key Laboratory of Applied Chemistry, and Nanotechnology at Universities of Jilin, 7989 Weixing Road, Changchun, Jilin Province, 130022, P. R. China.

Flexible peculiarly structured [(Fe O /PVP)@(Tb(BA) phen/PVP)]//[PANI/PVP] (PVP=polyvinylpyrrolidone, BA=benzoic acid, phen=1,10-phenanthroline, and PANI=polyaniline) Janus nanofibers synchronously endowed with tuned and enhanced luminescent-magnetic-electrical trifunctionality have been prepared by electrospinning technology by using a homemade coaxis//monoaxis spinneret. It is satisfactorily found that the luminescent intensity of the peculiarly structured Janus nanofibers is higher than those of the counterpart conventional [nanofiber]//[nanofiber] Janus nanofibers and composite nanofibers owing to its peculiar nanostructure. Compared with the counterpart conventional Janus nanofibers of two independent partitions, the coaxial nanocable is used as one side of the peculiarly structured Janus nanofiber instead of nanofiber, and three independent partitions are successfully realized in the peculiarly structured Janus nanofiber, thus the interferences among various functions are further reduced, leading to the fact that excellent multifunctionalities can be obtained. The Janus nanofibers possess excellent green luminescence, superparamagnetism, and electric conductivity, and further, these performances can be, respectively, tunable by modulating the Tb(BA) phen, Fe O , and PANI contents. The design philosophy and construction technique for the peculiarly structured Janus nanofibers provide guidance for fabricating other multifunctional Janus nanofibers with various performances.
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http://dx.doi.org/10.1002/cplu.201800030DOI Listing
March 2018

Double anisotropic electrically conductive flexible Janus-typed membranes.

Nanoscale 2017 Dec;9(47):18918-18930

Key Laboratory of Applied Chemistry and Nanotechnology at Universities of Jilin Province, Changchun University of Science and Technology, Changchun 130022, China.

Novel type III anisotropic conductive films (ACFs), namely flexible Janus-typed membranes, were proposed, designed and fabricated for the first time. Flexible Janus-typed membranes composed of ordered Janus nanobelts were constructed by electrospinning, which simultaneously possess fluorescence and double electrically conductive anisotropy. For the fabrication of the Janus-typed membrane, Janus nanobelts comprising a conductive side and an insulative-fluorescent side were primarily fabricated, and then the Janus nanobelts are arranged into parallel arrays using an aluminum rotary drum as the collector to obtain a single anisotropically conductive film. Subsequently, a secondary electrospinning process was applied to the as-prepared single anisotropically conductive films to acquire the final Janus-typed membrane. For this Janus-typed membrane, namely its left-to-right structure, anisotropic electrical conduction synchronously exists on both sides, and furthermore, the two electrically conductive directions are perpendicular. By modulating the amount of Eu(BA)phen complex and conducting polyaniline (PANI), the characteristics and intensity of the fluorescence-electricity dual-function in the membrane can be tuned. The high integration of this peculiar Janus-typed membrane with simultaneous double electrically conductive anisotropy-fluorescent dual-functionality is successfully realized in this study. This design philosophy and preparative technique will provide support for the design and construction of new types of special nanostructures with multi-functionality.
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http://dx.doi.org/10.1039/c7nr06456jDOI Listing
December 2017

Integrating photoluminescence, magnetism and thermal conversion for potential photothermal therapy and dual-modal bioimaging.

J Colloid Interface Sci 2018 Jan 22;510:292-301. Epub 2017 Sep 22.

Key Laboratory of Applied Chemistry and Nanotechnology at University of Jilin Province, Changchun University of Science and Technology, Changchun 130022, China.

Multifunctional nanocomposites (NCs) incorporating magnetic, luminescent and photothermal conversion properties are endowed with potential application in many fields such as imaging, tumor detection, drug delivery and therapy. Here, multifunctional MWCNTs-NaGdF:Yb, Er, Eu NCs, which offer the potential for integrated bioimaging and photothermal therapy (PTT) were fabricated by a facile hydrothermal method. The resulting sample exhibits uniform morphology, bright dual-modal luminescence and intrinsic paramagnetic properties. Under near-infrared laser excitation, NCs have excellent photothermal conversion properties. In addition, the MTT assay in HeLa cells shows that the NCs have good biocompatibility. Moreover, the up-conversion luminescence (UCL) imaging, X-ray computed tomography (CT) imaging and PTT in vitro of NCs were investigated. The results indicate that NCs can be used for dual-modal imaging-guided diagnose and PTT of cancer cells.
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http://dx.doi.org/10.1016/j.jcis.2017.09.085DOI Listing
January 2018

Nanostructured CoO/NiO/CoNi anodes with tunable morphology for high performance lithium-ion batteries.

Dalton Trans 2017 Aug;46(33):11031-11036

Key Laboratory of Applied Chemistry and Nanotechnology at Universities of Jilin Province, Department of Chemistry & Environmental Engineering, Changchun University of Science and Technology, Changchun, Jilin 130022, PR China.

Nanostructured CoO/NiO/CoNi composites as anode materials for lithium-ion batteries (LIBs) have been successfully prepared by a facile, straightforward, and large-scale dealloying method. The effects of NaOH solution concentration on the structure, morphology and electrochemical performances of the resulting products are studied systematically. These results indicate that the concentration of NaOH solution mainly influences the morphology of the CoO/NiO/CoNi composites. Cyclic voltammetry (CV) and charge-discharge tests have been conducted to assess the lithium storage performances of the CoO/NiO/CoNi anodes obtained from the 5 M NaOH solution. Remarkably, the CoO/NiO/CoNi anodes exhibit high specific capacity, excellent rate properties, and superb cycling stability. A reversible capacity is still maintained at 575 mA h g after 500 cycles at a current density of 200 mA g. Even at a current rate of 2000 mA g, the capacity could reach 267 mA h g. The outstanding electrochemical properties of the CoO/NiO/CoNi anodes make them promising anode materials of LIBs and other energy storage applications.
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http://dx.doi.org/10.1039/c7dt01904aDOI Listing
August 2017

Dual-mode blue emission, enhanced up-conversion luminescence and paramagnetic properties of ytterbium and thulium-doped BaGdF multifunctional nanophosphors.

J Colloid Interface Sci 2017 Sep 22;501:215-221. Epub 2017 Apr 22.

Key Laboratory of Applied Chemistry and Nanotechnology at University of Jilin Province, Changchun University of Science and Technology, Changchun 130022, China.

A series of BaGdF:Yb, Tm nanophosphors (NPs) with dual-mode (down-conversion (DC) and upconversion (UC)) luminescence were successfully prepared by hydrothermal method at 180°C. The NPs have sphere-like morphology and cubic structure. Under the excitation of ultraviolet 355nm and near-infrared 980nm, Yb and Tm ions co-doped BaGdF phosphors exhibit bright blue dual-mode emission. The mechanism of UC emissions was determined three-photon absorption. The energy transfer processes from Yb to Tm were discussed in detail. The up-conversion luminescence of BaGdF:Yb/Tm nanophosphors were enhanced by introducing the sensitizer Yb ions and modifying the cetyltrimethylammonium bromide (CTAB) surfactant, respectively. Moreover, the as-prepared samples exhibit paramagnetic properties at room temperature. This type of multifunctional nanophosphors have promising applications in anti-counterfeiting, drug delivery, solid state lasers, biolabels, MRI, light emitting diodes (LEDs).
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http://dx.doi.org/10.1016/j.jcis.2017.04.066DOI Listing
September 2017

Assembly of 1D nanofibers into a 2D bi-layered composite nanofibrous film with different functionalities at the two layers via layer-by-layer electrospinning.

Phys Chem Chem Phys 2016 Dec;19(1):118-126

Key Laboratory of Applied Chemistry and Nanotechnology at Universities of Jilin Province, Changchun University of Science and Technology, Changchun 130022, China.

A two-dimensional (2D) bi-layered composite nanofibrous film assembled by one-dimensional (1D) nanofibers with trifunctionality of electrical conduction, magnetism and photoluminescence has been successfully fabricated by layer-by-layer electrospinning. The composite film consists of a polyaniline (PANI)/FeO nanoparticle (NP)/polyacrylonitrile (PAN) tuned electrical-magnetic bifunctional layer on one side and a Tb(TTA)(TPPO)/polyvinylpyrrolidone (PVP) photoluminescent layer on the other side, and the two layers are tightly combined face-to-face together into the novel bi-layered composite film of trifunctionality. The brand-new film has totally different characteristics at the double layers. The electrical conductivity and magnetism of the electrical-magnetic bifunctional layer can be, respectively, tunable via modulating the PANI and FeO NP contents, and the highest electrical conductivity can reach up to the order of 10 S cm, and predominant intense green emission at 545 nm is obviously observed in the photoluminescent layer under the excitation of 357 nm single-wavelength ultraviolet light. More importantly, the luminescence intensity of the photoluminescent layer remains almost unaffected by the electrical-magnetic bifunctional layer because the photoluminescent materials have been successfully isolated from dark-colored PANI and FeO NPs. By comparing with the counterpart single-layered composite nanofibrous film, it is found that the bi-layered composite nanofibrous film has better performance. The novel bi-layered composite nanofibrous film with trifunctionality has potential in the fields of nanodevices, molecular electronics and biomedicine. Furthermore, the design conception and fabrication technique for the bi-layered multifunctional film provide a new and facile strategy towards other films of multifunctionality.
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http://dx.doi.org/10.1039/c6cp05935jDOI Listing
December 2016

Narrow-band red emitting phosphor BaTiF:Mn: preparation, characterization and application for warm white LED devices.

Dalton Trans 2016 Nov 24;45(44):17886-17895. Epub 2016 Oct 24.

Key Laboratory of Applied Chemistry and Nanotechnology at Universities of Jilin Province, Changchun University of Science and Technology, Changchun 130022, P. R. China.

As a new class of non-rare-earth red phosphors for high-efficiency warm white light-emitting diodes (white LEDs), Mn ion activated fluoride compounds have been extensively investigated recently and hold the potential to supersede commercial rare earth doped nitride phosphors. Herein, a series of Mn ions doped BaTiF phosphors have been prepared via the hydrothermal route using citric acid as a surfactant. After a systematic investigation, we illustrate the effects of reaction time, nominal concentration of HF solution, and reaction temperature on the luminescence performance of the phosphor. The BaTiF:Mn phosphor generates narrow red emission, which is highly perceived by the human eyes and leads to excellent chromatic saturation of red emission spectra. Simultaneously, concentration and thermal quenching are investigated systematically, and the quenching mechanisms are elucidated in detail. Employing BaTiF:Mn as a red phosphor, we fabricate a high-performance white LED with low correlated color temperature of 3974 K, high color rendering index of 90.6 and luminous efficacy of 132.54 lm W. Based on the improvement in correlated color temperature and color rendering index, the BaTiF:Mn red phosphor supplements the deficiency of LEDs fabricated by combining blue chips and only YAG:Ce, which suggests that it is a promising commercial red phosphor in warm white LEDs.
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http://dx.doi.org/10.1039/c6dt03398aDOI Listing
November 2016

NaGdF:Dy nanofibers and nanobelts: facile construction technique, structure and bifunctionality of luminescence and enhanced paramagnetic performances.

Phys Chem Chem Phys 2016 Oct;18(39):27536-27544

Key Laboratory of Applied Chemistry and Nanotechnology at Universities of Jilin Province, Changchun University of Science and Technology, Changchun 130022, China.

Luminescent-magnetic bifunctional NaGdF:Dy nanofibers and nanobelts have been successfully fabricated by a combination of electrospinning followed by subsequent calcination with fluorination technology for the first time. The structure, morphologies, and luminescence and magnetic properties of the synthesized materials have been investigated by a variety of techniques. X-ray diffraction (XRD) analysis shows that as-prepared NaGdF:Dy nanostructures are pure hexagonal structures. Scanning electron microscopy (SEM) observations indicate that directly electrospinning-made PVP/[NaNO + Gd(NO) + Dy(NO)] composite nanofibers and nanobelts have smooth surfaces, good dispersion and uniform size, and surfaces of NaGdF:Dy nanofibers and nanobelts become rough after calcination and fluorination processes. The mean diameters of PVP/[NaNO + Gd(NO) + Dy(NO)] composite nanofibers and NaGdF:0.5%Dy nanofibers are, respectively, 402.20 ± 2.39 nm and 246.06 ± 5.84 nm at the confidence level of 95%. The mean widths and thicknesses of PVP/[NaNO + Gd(NO) + Dy(NO)] composite nanobelts and NaGdF:0.5%Dy nanobelts are 4.16 ± 0.17 μm and 279 nm, and 0.83 ± 0.01 μm and 130 nm, respectively. Under the excitation of 274 nm ultraviolet light, NaGdF:Dy nanofibers and nanobelts show the predominant blue and yellow emission peaks at 478 and 570 nm corresponding to the F → H (J = 15, 13) energy level transitions of Dy ions, respectively. NaGdF:0.5%Dy nanofibers have higher photoluminescence intensity than their nanobelt counterpart. In addition, all the NaGdF:Dy nanofibers and nanobelts display superparamagnetic properties. The NaGdF:0.5%Dy nanobelts show the highest magnetization, and NaGdF:0.5%Dy nanofibers have slightly higher magnetization values than NaGdF nanofibers. NaGdF:Dy nanofibers and nanobelts simultaneously possess excellent luminescence and enhanced superparamagnetic properties, which make them ideally suitable for application in many fields such as solid-state lasers, lighting and displays, and magnetic resonance imaging. The design conception and construction strategy developed in this work may provide some new guidance for the synthesis of other rare earth fluoride nanostructures with various morphologies.
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http://dx.doi.org/10.1039/c6cp05058aDOI Listing
October 2016

Novel Electrospun Dual-Layered Composite Nanofibrous Membrane Endowed with Electricity-Magnetism Bifunctionality at One Layer and Photoluminescence at the Other Layer.

ACS Appl Mater Interfaces 2016 Oct 22;8(39):26226-26234. Epub 2016 Sep 22.

Key Laboratory of Applied Chemistry and Nanotechnology at Universities of Jilin Province, Changchun University of Science and Technology , Changchun 130022, China.

Dual-layered composite nanofibrous membrane equipped with electrical conduction, magnetism and photoluminescence trifunctionality is constructed via electrospinning. The composite membrane consists of a polyaniline (PANI)/FeO nanoparticles (NPs)/polyacrylonitrile (PAN) tuned electrical-magnetic bifunctional nanofibrous layer at one side and a Eu(TTA)(TPPO)/polyvinylpyrrolidone (PVP) photoluminescent nanofibrous layer at the other side, and the two layers are tightly combined face-to-face together into the novel dual-layered composite membrane with trifunctionality. The electric conductivity and magnetism of electrical-magnetic bifunctionality can be respectively tunable via modulating the respective PANI and FeO NPs contents, and the highest electric conductivity approaches the order of 1 × 10 S cm. Predominant red emission at 615 nm can be obviously observed in the photoluminescent layer under 366 nm excitation. Moreover, the luminescent intensity of photoluminescent layer is almost unaffected by the electrical-magnetic bifunctional layer because of the fact that the photoluminescent materials have been successfully isolated from dark-colored PANI and FeO NPs. The novel dual-layered composite nanofibrous membrane with trifunctionality has potentials in many fields. Furthermore, the design philosophy and fabrication method for the dual-layered multifunctional membrane provide a new and facile strategy toward other membranes with multifunctionality.
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http://dx.doi.org/10.1021/acsami.6b08522DOI Listing
October 2016

Dual-mode, tunable color, enhanced upconversion luminescence and magnetism of multifunctional BaGdF5:Ln(3+) (Ln = Yb/Er/Eu) nanophosphors.

Phys Chem Chem Phys 2016 Aug;18(31):21518-26

Key Laboratory of Applied Chemistry and Nanotechnology at Universities of Jilin Province, Changchun University of Science and Technology, Changchun, China.

A series of Yb(3+), Er(3+), and Eu(3+) ions doped BaGdF5 dual-mode (down-conversion (DC) and upconversion (UC)) luminescent nanophosphors were successfully prepared by a simple one-step hydrothermal method. X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), energy-dispersive X-ray spectrometry (EDS), Fourier-transform infrared (FTIR) spectroscopy, photoluminescence (PL) spectroscopy, fluorescence lifetime measurements, and vibrating sample magnetometry (VSM) were utilized to characterize the samples. Under 274 nm UV light excitation, BaGd0.78-zF5:0.2Yb(3+),0.02Er(3+),zEu(3+) phosphors emitted orange emission. Under 980 nm NIR irradiation, intense up-converted visible green emissions were observed in BaGdF5:Yb(3+),Er(3+)/Eu(3+) samples. The mechanism of UC emissions involved two-photon absorption. In the Yb(3+),Er(3+),Eu(3+) co-doped BaGdF5 phosphors, the energy transfer processes from Gd(3+) to Eu(3+) and from Yb(3+) to Er(3+) were discussed. Tunable colors were visualised with the help of the Commission Internationale de L'Eclairage (CIE) chromaticity diagram and the processes responsible for the DC and UC emissions were discussed in detail. The enhanced up-conversion luminescence of Yb(3+),Er(3+)/Eu(3+) co-doped BaGdF5 nanophosphors (NPs) was realized by modifying the trisodium citrate (Cit(3-)) surfactant. Moreover, the as-prepared samples exhibited paramagnetic properties at room temperature. This type of multifunctional orange-green emitting nanophosphor has promising applications in solid state lasers, lighting, MRI, anti-counterfeiting, biolabels, and so on.
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http://dx.doi.org/10.1039/c6cp03743gDOI Listing
August 2016

Flexible Tricolor Flag-liked Microribbons Array with Enhanced Conductive Anisotropy and Multifunctionality.

Sci Rep 2015 Sep 28;5:14583. Epub 2015 Sep 28.

Key Laboratory of Applied Chemistry and Nanotechnology at Universities of Jilin Province, Changchun University of Science and Technology, Changchun 130022.

Anisotropically conductive materials are important components in subminiature devices. However, at this stage, some defects have limited practical applications of them, especially low anisotropic degree and high cost. Here, we report novel tricolor flag-liked microribbons array prepared by electrospinning technique. The tricolor flag-liked microribbons array is composed of parallel microribbons, and each microribbon consists of three different regions, just like tricolor flag. The tricolor flag-liked microribbons array is only electrically conductive in the direction parallel to the microribbons, whereas in the perpendicular and thickness directions are insulative. The electrical conductivity along parallel direction reaches up to 8 orders of magnitude higher than that along perpendicular direction. The degree of anisotropy in present study is increased by 2 orders of magnitude than that of the anisotropically conductive material in references reported before. Besides, other functions can be conveniently assembled into tricolor flag-liked microribbons array to realize multifunctionality. Owing to the high electrical anisotropy and multifunctionality, tricolor flag-liked microribbons array will have important applications. Furthermore, a universal technique to prepare microribbons with three functional regions has been established for fabricating excellent multifunctional materials.
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http://dx.doi.org/10.1038/srep14583DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4585964PMC
September 2015

Tunable photoluminescence and magnetic properties of Dy(3+) and Eu(3+) doped GdVO4 multifunctional phosphors.

Phys Chem Chem Phys 2015 Oct;17(40):26638-44

Key Laboratory of Applied Chemistry and Nanotechnology at Universities of Jilin Province, Changchun University of Science and Technology, Changchun, China.

A series of Dy(3+) or/and Eu(3+) doped GdVO4 phosphors were successfully prepared by a simple hydrothermal method and characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), energy-dispersive X-ray spectrometry (EDS), photoluminescence (PL) spectroscopy and vibrating sample magnetometry (VSM). The results indicate that the as-prepared samples are pure tetragonal phase GdVO4, taking on nanoparticles with an average size of 45 nm. Under ultraviolet (UV) light excitation, the individual Dy(3+) or Eu(3+) ion activated GdVO4 phosphors exhibit excellent emission properties in their respective regions. The mechanism of energy transfer from the VO4(3-) group and the charge transfer band (CTB) to Dy(3+) and Eu(3+) ions is proposed. Color-tunable emissions in GdVO4:Dy(3+),Eu(3+) phosphors are realized through adopting different excitation wavelengths or adjusting the appropriate concentration of Dy(3+) and Eu(3+) when excited by a single excitation wavelength. In addition, the as-prepared samples show paramagnetic properties at room temperature. This kind of multifunctional color-tunable phosphor has great potential applications in the fields of photoelectronic devices and biomedical sciences.
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http://dx.doi.org/10.1039/c5cp04373eDOI Listing
October 2015

Electrospun Flexible Coaxial Nanoribbons Endowed With Tuned and Simultaneous Fluorescent Color-Electricity-Magnetism Trifunctionality.

Sci Rep 2015 Sep 16;5:14052. Epub 2015 Sep 16.

Key Laboratory of Applied Chemistry and Nanotechnology at Universities of Jilin Province, Changchun University of Science and Technology, Changchun 130022, China.

In order to develop new-typed multifunctional nanocomposites, fluorescent-electrical-magnetic trifunctional coaxial nanoribbons with tunable fluorescent color, including white-light emission, have been successfully fabricated via coaxial electrospinning technology. Each stripe of coaxial nanoribbon is composed of a Fe3O4/PMMA core and a [Eu(BA)3phen+Dy(BA)3phen]/PANI/PMMA (PMMA = polymethyl methacrylate, BA = benzoic acid, phen = phenanthroline, polyaniline = PANI) shell. X-ray diffractometry (XRD), field emission scanning electron microscopy (FE-SEM), biological microscopy (BM), vibrating sample magnetometry (VSM), energy dispersive spectrometry (EDS), Hall effect measurement system and photoluminescence (PL) spectroscopy were employed to characterize the coaxial nanoribbons. Emitting color of the coaxial nanoribbons can be tuned by adjusting the contents of Dy(BA)3phen, Eu(BA)3phen, PANI and Fe3O4 in a wide color range of blue-white-orange under the excitation of 273-nm single-wavelength ultraviolet light. The coaxial nanoribbons simultaneously possess excellent luminescent performance, electrical conduction and magnetism compared with the counterpart composite nanoribbons. Furthermore, the electrical and magnetic performances of the coaxial nanoribbons also can be tunable by adding different quantities of PANI and Fe3O4 nanoparticles, respectively. The obtained coaxial nanoribbons have promising applications in many areas, such as electromagnetic interference shielding, microwave absorption, molecular electronics, biomedicine, future nanomechanics and display fields.
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http://dx.doi.org/10.1038/srep14052DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4571655PMC
September 2015

Synthesis and Luminescence Properties of Terbium-Doped Lanthanum Oxychloride Nanostructures.

J Nanosci Nanotechnol 2015 Jun;15(6):4304-15

LaOCl:Tb3+ nanofibers, nanotubes and nanobelts were prepared via electrospinning combined with a double-crucible chlorination technique using NH4Cl powders as chlorinating agent. Different morphologies of LaOCl:Tb3+ nanostructures were obtained through adjusting some of the electrospun parameters. The as-prepared LaOCl:Tb3+ nanostructures are tetragonal in structure with space group of P4/nmm. The diameters of LaOCl:Tb3+ nanofibers, nanotubes and the width of LaOCl:Tb3+ nanobelts are respectively 133.99 ± 16.95 nm, 140.57 ± 17.82 nm and 5.32 ± 0.63 μm under the 95% confidence level. Under the excitation of 230-nm ultraviolet light, the LaOCl:Tb3+ nanostructures emit the predominant emission peaks at 544 nm originated from the energy levels transition of 5D4 --> 7F5 of Tb3+ ions. The optimum molar percentage of Tb3+ in the LaOCl:Tb3+ nanofibers is 7%. LaOCl:Tb3+ nanobelts exhibit the strongest PL intensity of the three nanostructures under the same doping molar concentration. The possible formation mechanisms of LaOCl:Tb3+ nanostructures are also proposed.
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http://dx.doi.org/10.1166/jnn.2015.9708DOI Listing
June 2015

A novel strategy to directly fabricate flexible hollow nanofibers with tunable luminescence-electricity-magnetism trifunctionality using one-pot electrospinning.

Phys Chem Chem Phys 2015 Sep 13;17(35):22977-84. Epub 2015 Aug 13.

Key Laboratory of Applied Chemistry and Nanotechnology at Universities of Jilin Province, Changchun University of Science and Technology, Changchun 130022, China.

Novel photoluminescent-electrical-magnetic trifunctional flexible Eu(BA)3phen/PANI/Fe3O4/PVP (BA = benzoic acid, phen = phenanthroline, PANI = polyaniline, PVP = polyvinylpyrrolidone) hollow nanofibers were fabricated by a one-pot electrospinning technique using a specially designed coaxial spinneret for the first time. Very different from the traditional preparation process of hollow fibers via coaxial electrospinning, which needs to firstly fabricate the coaxial fibers and followed by removing the core through high-temperature calcination or solvent extraction, in our current study, no core spinning solution is used to directly fabricate hollow nanofibers. The morphology and properties of the obtained hollow nanofibers were characterized in detail using X-ray diffractometry, scanning electron microscopy, transmission electron microscopy, fluorescence spectroscopy, Fourier-transform infrared spectroscopy, a 4-point probe resistivity measurement system and vibrating sample magnetometry. The Eu(BA)3phen/PANI/Fe3O4/PVP hollow nanofibers, with outer diameters of ca. 305 nm and inner diameters of about 140 nm, exhibit excellent photoluminescence performance, electrical conductivity and magnetic properties. Fluorescence emission peaks of Eu(3+) are observed in the Eu(BA)3phen/PANI/Fe3O4/PVP hollow nanofibers and assigned to the (5)D0→(7)F0 (580 nm), (5)D0→(7)F1 (592 nm) and (5)D0→(7)F2 (616 nm) energy level transitions of Eu(3+) ions, and the (5)D0→(7)F2 hypersensitive transition at 616 nm is the predominant emission peak. The electrical conductivity of the hollow nanofibers reaches up to the order of 10(-3) S cm(-1). The luminescent intensity, electrical conductivity and magnetic properties of the hollow nanofibers can be tuned by adding various amounts of Eu(BA)3phen, PANI and Fe3O4 nanoparticles. The new-type photoluminescent-electrical-magnetic trifunctional flexible hollow nanofibers hold potential for a variety of applications, including electromagnetic interference shielding, microwave absorption, molecular electronics and biomedicine. The design conception and synthetic strategy developed in this study are of universal significance to construct other multifunctional hollow one-dimensional nanomaterials.
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http://dx.doi.org/10.1039/c5cp03522hDOI Listing
September 2015

Multifunctional MWCNTs-NaGdF4:Yb(3+),Er(3+),Eu(3+) hybrid nanocomposites with potential dual-mode luminescence, magnetism and photothermal properties.

Phys Chem Chem Phys 2015 Sep 10;17(35):22659-67. Epub 2015 Aug 10.

Key Laboratory of Applied Chemistry and Nanotechnology at Universities of Jilin Province, Changchun University of Science and Technology, Changchun 130022, P. R. China.

A novel dual-mode luminescence multifunctional hybrid nanomaterial has been successfully prepared by coating the NaGdF4:Yb(3+),Er(3+),Eu(3+) nanoparticles (NPs) on the surface of MWCNTs. The as-synthesized MWCNTs-NaGdF4:Yb(3+),Er(3+),Eu(3+) nanocomposites (NCs) can simultaneously take advantage of both magnetic and optical properties of NaGdF4:Yb(3+),Er(3+),Eu(3+) NPs and the photothermal conversion property of MWCNTs. The samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectrometry (EDS), vibrating sample magnetometry (VSM), UV-Vis absorption, luminescence spectroscopy and fluorescence lifetime measurements. Meanwhile, the photothermal conversion was examined under irradiation with a 980 nm laser. The results show that the MWCNTs-NaGdF4:Yb(3+),Er(3+),Eu(3+) NCs have preferably magnetic, dual-mode (up- and down-conversion) luminescence and photothermal properties. And the NCs have good biocompatibility, low toxicity and up-conversion luminescence for cell imaging. As a consequence, the dual-mode luminescence multifunctional nanomaterials have potential applications in environmental science fields and clinical fields for magnetic resonance imaging, fluorescence imaging, photothermal therapy, bioseparation and targeted drug delivery.
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http://dx.doi.org/10.1039/c5cp03725eDOI Listing
September 2015

Novel flexible belt-shaped coaxial microcables with tunable multicolor luminescence, electrical conductivity and magnetism.

Phys Chem Chem Phys 2015 Sep 3;17(34):21845-55. Epub 2015 Aug 3.

Key Laboratory of Applied Chemistry and Nanotechnology at Universities of Jilin Province, Changchun University of Science and Technology, Changchun 130022, China.

A novel type of flexible [Fe3O4/PANI/PMMA]@{[Eu(BA)3phen + Tb(BA)3phen]/PMMA} (PMMA = polymethyl methacrylate, BA = benzoic acid, phen = phenanthroline, PANI = polyaniline) belt-shaped coaxial microcable possessing electrical conductivity, magnetism and color-tunable photoluminescence has been successfully fabricated by electrospinning technology using a specially designed coaxial spinneret. Every strip of belt-shaped coaxial microcable is assembled with a Fe3O4/PANI/PMMA electrically conductive -magnetic bifunctional core and a [Eu(BA)3phen + Tb(BA)3phen]/PMMA insulative and photoluminescence-tunable shell. The conductivity of the core of belt-shaped coaxial microcables reaches up to the order of 10(-2) S cm(-1) and all belt-shaped coaxial microcables are insulated from each other. The tuning of emission color is possible by changing the Eu(3+)/Tb(3+) molar ratio of the belt-shaped coaxial microcables. The electrical conductivity, magnetic and photoluminescence properties of belt-shaped coaxial microcables can be tuned by adjusting the content of PANI, Fe3O4 nanoparticles (NPs) and rare earth complexes. More importantly, the proposed design idea and the construction technique are universal regarding the preparation of other multifunctional one-dimensional micromaterials.
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http://dx.doi.org/10.1039/c5cp03185kDOI Listing
September 2015

Controlled synthesis and near-infrared luminescence of LaOBr:Nd3+ nanofibers and nanobelts.

J Nanosci Nanotechnol 2014 Aug;14(8):6196-201

LaOBr:Nd(3+) nanofibers and nanobelts were synthesized for the first time via calcinating the electrospun PVP/[La(NO3)3 + Nd(NO3)3 + NH4Br] composites. X-ray diffraction (XRD) analysis revealed that LaOBr:Nd(3+) nanofibers and nanobelts are tetragonal in structure with the space group of P4/nmm. The morphologies and sizes of LaOBr:Nd(3+) nanostructures were investigated by scanning electron microscope (SEM). The mean diameter of the LaOBr:Nd(3+) nanofibers is 192.41 ± 18.97 nm. The width and thickness of the LaOBr:Nd(3+) nanobelts are 5.50 ± 0.48 μm and 112 nm, respectively. Under the excitation of 532-nm laser, LaOBr:Nd(3+) nanostructures exhibit the characteristic emissions of predominant peaks at 922, 1072 and 1345 nm, attributed to (4)F3/2 --> (4)I9/2, (4)F3/2 --> (4)I11/2 and (4)F3/2 --> (4)I13/2 energy levels transitions of Nd(3+) ions, respectively. The optimum doping molar concentration of the Nd(3+) ions in the LaOBr:Nd(3+) nanofibers is 1.0%. Interestingly, we found that the luminescence intensity of nanobelts is obviously greater than that of the nanofibers for LaOBr:Nd(3+) under the same measuring conditions. The formation mechanisms of LaOBr:Nd(3+) nanofibers and nanobelts were also proposed.
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http://dx.doi.org/10.1166/jnn.2014.8865DOI Listing
August 2014

Single Flexible Janus Nanobelts to Realize Tunable and Enhanced Simultaneous Photoluminescent, Electrical, and Magnetic Trifunctionality.

Chempluschem 2015 Mar 3;80(3):568-575. Epub 2014 Dec 3.

Changchun University of Science and Technology, Key Laboratory of Applied Chemistry and Nanotechnology at Universities of Jilin, 7989 Weixing Road, Changchun 130022 (P. R. China), Fax: (+86)-431-8538-3815.

Y O :Eu nanoparticles (NPs), polyaniline (PANI), and Fe O NPs are incorporated into polymethyl methacrylate (PMMA) and electrospun into [Y O :Eu /PMMA]//[PANI/Fe O /PMMA] Janus nanobelts with Y O :Eu /PMMA as one half side and PANI/Fe O /PMMA as the other. The morphology and properties of the final products are investigated in detail by X-ray diffraction (XRD), scanning electron microscopy (SEM), optical microscopy (OM), energy-dispersive spectrometry (EDS), Hall effect measurements, fluorescence spectroscopy, vibrating sample magnetometry (VSM), and UV/Vis spectroscopy. The results reveal that the [Y O :Eu /PMMA]//[PANI/Fe O /PMMA] trifunctional Janus nanobelts possess excellent electrical conductivity, magnetism, and fluorescence owing to their special nanostructure. Fluorescence emission peaks of Eu are observed in the Janus nanobelts. The electrical conductivity reaches the order of 10  S cm . The luminescent intensity, electrical conductivity, and saturation magnetization of the Janus nanobelts can be tuned by adjusting the respective amounts of Y O :Eu NPs, PANI, and Fe O NPs. The flexible luminescent-electrical-magnetic trifunctional Janus nanobelts have many potential applications. More importantly, this design concept and construct technology is of universal significance for the fabrication of other multifunctional nanostructures.
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http://dx.doi.org/10.1002/cplu.201402334DOI Listing
March 2015

Electrospinning preparation and photoluminescence properties of Y3Al5O12:Tb3+ nanostructures.

Luminescence 2015 Sep 26;30(6):751-9. Epub 2014 Nov 26.

Key Laboratory of Applied Chemistry and Nanotechnology at Universities of Jilin Province, Changchun University of Science and Technology, Changchun, China.

Novel nanostructures of Y3Al5O12:Tb(3+) (denoted as YAG:Tb(3+) for short) nanobelts and nanofibers were fabricated by calcination of the respective electrospun PVP/[Y(NO3)3 + Tb(NO3)3 + Al(NO3)3] composite nanobelts and nanofibers. YAG:Tb(3+) nanostructures are cubic in structure with a space group of Ia 3d. The thickness and width of the YAG:7%Tb(3+) nanobelts are respectively ca. 125 nm and 5.9 ± 0.3 m, and the diameter of YAG:7%Tb(3+) nanofibers is 166.0 ± 20 nm (95% confidence level). The YAG:Tb(3+) nanostructures emit predominantly at 544 nm from the energy levels transition of (5) D4 → (7) F5 of Tb(3+) ions under the excitation of 274-nm ultraviolet light. It was found that the optimum doping molar concentration of Tb(3+) ions for YAG:Tb(3+) nanostructures was 7%. Compared with YAG:7%Tb(3+) nanofibers, YAG:7%Tb(3+) nanobelts exhibit a stronger photoluminescence (PL) intensity under the same doping concentration. Commission International de l'Eclairage (CIE) analysis demonstrates that the emitting colors of YAG:Tb(3+) nanostructures are located in the green region and color-tuned luminescence can be obtained by changing the doping concentration of Tb(3+) and morphologies of the nanostructures, which could be applied in the field of optical telecommunication and optoelectronic devices. The possible formation mechanisms of YAG:Tb(3+) nanobelts and nanofibers are also proposed.
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http://dx.doi.org/10.1002/bio.2816DOI Listing
September 2015
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