Co-reporter:Chengpeng Yao;Yun Fan;Maozhong Zhou ;Hai Wu
Crystal Research and Technology 2015 Volume 50( Issue 7) pp:566-573
Publication Date(Web):
DOI:10.1002/crat.201500063
Elliptic NdCrO3 microplates were synthesized by a simple and facile one-step hydrothermal method of processing temperature 280 °C for 3 days. The products prepared in this paper have been characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), X-ray fluorescence (XRF), Fourier transform infrared spectroscopy (FTIR) and field-emission scanning electron microscopy (FESEM). The magnetic properties of the final sample are also studied. The XRD pattern indicates the pure orthorhombic phase for NdCrO3 particles, the XPS, XRF and FTIR results further demonstrate the composition and purity of the final product. A possible growth mechanism for elliptic NdCrO3 microplates is proposed. Through the investigation of magnetic properties, it can be generally concluded that the orthorhombic elliptic NdCrO3 microplates exhibit typical behaviors of magnetic transition, spin reorientation transition and magnetic exchange bias. The Néel temperature is 218 K and the spin reorientation transition temperature is 46 K. The hysteresis loop under 5 K shows that the value of exchange bias field (Hex) is 12 Oe and the shift of remanent magnetization (ΔM) is 0.008 emu/g, respectively.
Co-reporter:Youjin Zhang, Chengpeng Yao, Yun Fan, Maozhong Zhou
Materials Research Bulletin 2014 59() pp: 387-393
Publication Date(Web):
DOI:10.1016/j.materresbull.2014.07.049
Co-reporter:You-jin Zhang;Zhen-yu Xu;Xiao-bin Yin
Chemical Research in Chinese Universities 2013 Volume 29( Issue 5) pp:841-844
Publication Date(Web):2013 October
DOI:10.1007/s40242-013-3022-x
GdOHCO3 rhombic microcrystals were synthesized by hydrothermal method with urea used as the precipitator. Experimental parameters, such as the molar ratio of the starting reagents, reaction temperature and reaction time were examined. The as-obtained product was characterized by powder X-ray diffraction(XRD), field-emission scanning electron microscopy(FESEM), X-ray photoelectron spectroscopy(XPS), Fourier transform infrared spectroscopy(FTIR) and spectrofluorometry. The main reactions to form GdOHCO3 were proposed. In addition, the photoluminescence(PL) properties of GdOHCO3 rhombic microcrystals were discussed. The broad band located between 350 nm and 600 nm in the emission spectrum can be attributed to the self-trapped exciton luminescence.
Co-reporter:Youjin Zhang, Ao Zheng, Xiaozhi Yang, Hongmei He, Yun Fan and Chengpeng Yao
CrystEngComm 2012 vol. 14(Issue 24) pp:8432-8439
Publication Date(Web):26 Sep 2012
DOI:10.1039/C2CE26233A
Orthorhombic cubic GdFeO3 particles were synthesised by a simple and facile hydrothermal method. The products prepared in this paper were characterized by X-ray diffraction, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy and field-emission scanning electron microscopy. The formation mechanism of the cubic GdFeO3 particles was discussed. Through the investigation of the photoluminescence and magnetic properties, the orthorhombic cubic GdFeO3 particles exhibited very good doped luminescence, which emits different colored light when doped with different rare earth elements. The GdFeO3 particles present paramagnetic properties. It could be an excellent luminescence and magnetic material.
Co-reporter:Youjin Zhang, Hongmei He, Xiaozhi Yang, Ao Zheng, Yun Fan
Powder Technology 2012 Volume 224() pp:175-182
Publication Date(Web):July 2012
DOI:10.1016/j.powtec.2012.02.050
Co-reporter:Youjin Zhang, Ao Zheng, Xiaozhi Yang, Hongmei He, Yun Fan
Materials Research Bulletin 2012 47(9) pp: 2364-2368
Publication Date(Web):
DOI:10.1016/j.materresbull.2012.05.023
Co-reporter:Youjin Zhang, Hongmei He, Wei Zhu and Ao Zheng
CrystEngComm 2011 vol. 13(Issue 21) pp:6471-6480
Publication Date(Web):26 Aug 2011
DOI:10.1039/C1CE05518F
Uniform nanoerythrocyte-like, dodecahedron and spindle-like LuVO4 had been successfully synthesized on a large scale by a simple complex agent assisted hydrothermal method. The nanoerythrocyte-like LuVO4 was characterized by X-ray diffraction, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, field-emission scanning electron microscopy, high-resolution transmission electron microscopy, photoluminescence and cathodoluminescence. The possible formation mechanism of the LuVO4 with different morphologies were proposed. The LuVO4:Ln3+ (Ln = Sm, Eu, Dy, Er and Tm) phosphors show strong light emissions with different colors due to the different activator ions under ultraviolet light excitation or low-voltage electron beam excitation and the LuVO4:Sm3+ samples with different complex agents exhibit interesting morphology-dependent optical properties. The complex-agents-assisted hydrothermal synthesis provides us one method to explore the special morphology of nano/micromaterials and the new optical materials.
Co-reporter:Hongmei He, Youjin Zhang, Wei Zhu, Ao Zheng
Materials Research Bulletin 2011 46(10) pp: 1546-1552
Publication Date(Web):
DOI:10.1016/j.materresbull.2011.06.029
Co-reporter:Youjin Zhang;Zhenyu Xu;Xiaobin Yin;Zhiyong Fang;Wei Zhu ;Hongmei He
Crystal Research and Technology 2010 Volume 45( Issue 11) pp:1183-1188
Publication Date(Web):
DOI:10.1002/crat.201000342
Abstract
EuCO3OH microspheres have been successfully prepared using a facile hydrothermal approach, by using urea as the precipitant without the assistance of any surfactants or templates. Several experimental parameters were examined, such as the reaction temperature, the reaction time, and the molar ratios of the starting reagents. The Eu2O3 microspheres have been prepared by thermal conversion of EuCO3OH microspheres at 800 °C in air for 6 h. The as-obtained products were characterized by X-ray diffraction, scanning electron microscopy, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, thermogravimetry–differential thermal analysis and photoluminescence. The possible growth process for the EuCO3OH microspheres was discussed. (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)
Co-reporter:Xiaobin Yin, ;Zhiyong Fang;Zhenyu Xu;Wei Zhu ;Hongmei He
Crystal Research and Technology 2010 Volume 45( Issue 9) pp:961-964
Publication Date(Web):
DOI:10.1002/crat.200900739
Abstract
Cross-like Pr2(C2O4)3·10H2O micro-particles were synthesized through a simple precipitation method at room temperature. The products were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), field-emission scanning electron microscopy (FESEM), thermogravimetry–differential thermal analysis (TG-DTA) and photoluminescence (PL). The possible formation mechanism of the cross-like Pr2(C2O4)3·10H2O micro-particles was discussed, and Pr6O11 with similar morphology was obtained by calcining the oxalate precursor. (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)
Co-reporter:Zhenyu Xu, Youjin Zhang, Zhiyong Fang, Xiaobin Yin, Wei Zhu
Materials Research Bulletin 2010 45(1) pp: 74-79
Publication Date(Web):
DOI:10.1016/j.materresbull.2009.08.014
Co-reporter:Kaidong Han, Youjin Zhang, Tao Cheng, Zhiyong Fang, Minrui Gao, Zhenyu Xu, Xiaobin Yin
Materials Chemistry and Physics 2009 Volume 114(Issue 1) pp:430-433
Publication Date(Web):15 March 2009
DOI:10.1016/j.matchemphys.2008.09.057
X-ray powder diffraction, transmission electron microscopy, and field-emission scanning electron microscopy were adopted to investigate the evolution process of Dy2O3 precursor microspheres and tripod-like structures, and a possible self-assembled process was identified during the morphology evolution. The same Dy2O3 microspheres and tripod-like structures were obtained by the calcination of the Dy2O3 precursors. The Dy2O3 microspheres with the diameter of 200–300 nm are consisted of the nanoparticles, while tripod-like structures were assembled from variform bulky particles that were evolved from microspheres, the lengths of three arms are nearly the same about 10 μm, and the angle between two arms is about 120°. Photoluminescence measurement shows that Dy2O3 microspheres and tripod-like structures have one broad emission peak centered at 430 nm with the 341 nm excitation.
Co-reporter:Youjin Zhang, Qixiu Hu, Biao Hu, Zhiyong Fang, Yitai Qian, Zude Zhang
Materials Chemistry and Physics 2006 Volume 96(Issue 1) pp:16-21
Publication Date(Web):10 March 2006
DOI:10.1016/j.matchemphys.2005.06.028
The composite oxide CuO/Mn3O4 and its mesoporous composite were prepared through co-precipitation method. The preparation conditions of CuO/Mn3O4 were tested and ascertained as following: Mn:Cu, 2:1; NaOH solution, 25% (w/w); volume, 6 mL; without aging; drying temperature, 90 °C; calcination temperature, 200 °C; calcination time, 3 h. CuO/Mn3O4, the mesoporous solid, and the mesoporous composite were characterized by X-ray power diffraction (XRD), high-resolution transmission electron microscope (HRTEM). The HRTEM image showed that CuO/Mn3O4 had been loaded into the pores of the mesoporous solid and the average diameter of CuO/Mn3O4 particles was about 4 nm. The specific surface area and the aperture distribution of the mesoporous solid and the mesoporous composite were measured by N2 adsorption. The catalytic activity and stability of CuO/Mn3O4 and the mesoporous composite were evaluated on a small fixed reaction bed and an online GC. The tar and some other harmful components in cigarette smoke can be reduced by using dual-filters containing the mesoporous composite. Comparing with the reference cigarette smoke, the tar, CO, benzo[α] pyrene and tobacco-specific N-nitrosoamines (TSNAs) in the tested cigarette smoke were reduced by 27.2, 23.8, 30.1, and 38.1%, respectively.
Co-reporter:Youjin Zhang, Hangmin Guan
Materials Research Bulletin 2005 Volume 40(Issue 9) pp:1536-1543
Publication Date(Web):1 September 2005
DOI:10.1016/j.materresbull.2005.04.019
Hexagonal LaPO4 (rhabdophane) nanofibers are synthesized and characterized. TEM images show that the synthesized LaPO4 nanofibers are about 5–50 nm in diameter and up to several micrometers long. The morphologies of the product are strongly dependent on the pH value of the reaction solution.
Co-reporter:Hangmin Guan, Youjin Zhang
Journal of Solid State Chemistry 2004 Volume 177(Issue 3) pp:781-785
Publication Date(Web):March 2004
DOI:10.1016/j.jssc.2003.09.010
Hexagonal and monoclinic NdPO4 nanowires about 5–50 nm in diameter and up to several micrometers long were prepared through hydrothermal reaction in 100°C and 220°C, respectively. The products were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectra (XPS), and high-resolution transmission electron microscopy (HRTEM). Furthermore, both the temperature and the pH value influence on the products were investigated.
Co-reporter:Youjin Zhang, Kaidong Han, Xiaobin Yin, Zhiyong Fang, Zhenyu Xu, Wei Zhu
Journal of Crystal Growth (15 July 2009) Volume 311(Issue 15) pp:3883-3888
Publication Date(Web):15 July 2009
DOI:10.1016/j.jcrysgro.2009.06.024
Single-crystalline PrCO3OH dodecahedral microrods with an orthorhombic structure have been successfully synthesized by the hydrothermal method used urea as the precipitator. Pr6O11 dodecahedral microrods have been obtained by thermal conversion of PrCO3OH dodecahedral microrods at 600 °C in air for 6 h. The as-synthesized products were characterized by X-ray powder diffraction, field-emission scanning electron microscope, transmission electron microscopy, high-resolution transmission electron microscopy, selected-area electron diffraction, X-ray photoelectron spectra, fourier transform infrared spectroscopy and thermogravimetry–differential thermal analysis. The effect of the reaction parameters on the morphology of the product has been investigated. The dodecahedral microrods with larger size and better crystallinity can be obtained under the higher reaction temperature. The possible formation mechanism of PrCO3OH microrods was discussed.
Co-reporter:Hongmei He, Youjin Zhang, Wei Zhu, Ao Zheng, Zhiyong Fang
Journal of Crystal Growth (15 August 2011) Volume 329(Issue 1) pp:71-76
Publication Date(Web):15 August 2011
DOI:10.1016/j.jcrysgro.2011.06.046
Nanoerythrocyte-like, dodecahedron and nanoparticle HoVO4 with high uniform size had been successfully synthesized on a large scale by a simple and facile complex agent assisted hydrothermal method. The nanoerythrocyte-like HoVO4 was characterized by X-ray diffraction, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, field-emission scanning electron microscopy, high-resolution transmission electron microscopy, and photoluminescence. The possible formation mechanism of the nanoerythrocyte-like HoVO4 was proposed. The PL results showed the pure HoVO4 products with different size and morphology displayed the same emission band with diverse relative intensity under the excitation of 455 nm and the red emission transition 5F5→5I8 was the most prominent group, whose peak situated at 659 nm. Furthermore, this general and facile method may be applied in the synthesis of other lanthanide compounds with nanoerythrocyte-like morphology.Highlights► Nanoerythrocyte-like HoVO4 had been synthesized on a large scale by a facile complex agent assisted hydrothermal method. ► Possible mechanisms of the nanoerythrocyte-like HoVO4 was proposed. ► The PL spectra of the HoVO4 with different size and morphology displayed the same emission band with diverse relative intensity. ► The PL of the HoVO4 illuminate the size and morphology of material play a critical role in the PL intensity.
