Epitaxial YBCO films were deposited on （100） LaAlO3 single-crystal substrates by metalorganic deposition of metal trifluoroacetate precursors with different concentrations. All the YBCO films have Tc around 91 K and...Epitaxial YBCO films were deposited on （100） LaAlO3 single-crystal substrates by metalorganic deposition of metal trifluoroacetate precursors with different concentrations. All the YBCO films have Tc around 91 K and Jc excess 2 MA/cm^2 at 77 K in zero field. XRD θ-2θscans show all the films have c-axis normal orientation. The FWHM （full width at half-maximum intensity） values of X-ray ω-scans of （005） reflection are 0.379°, 0.283°, and 0.543° for the YBCO thin films deposited with precursor solution concentrations of 1.52, 1.0, and 0.75 mol/L, respectively. With the concentration of the precursors decreasing, the thickness of the films decreases linearly. SEM micrographs show that porosities in the films become bigger with the precursor solution concentration decreasing. The big porosities in the film with the lowest concentration precursor deteriorate the superconducting property and make it have a wider superconducting transition and a lower Jc.展开更多
Pb0.97La0.02Zr0.95Ti0.05O3(PLZT)antiferroelectric thick films derived from different precursor solution concentrations are prepared on platinized silicon substrates by sol-gel processing.The films present polycrystall...Pb0.97La0.02Zr0.95Ti0.05O3(PLZT)antiferroelectric thick films derived from different precursor solution concentrations are prepared on platinized silicon substrates by sol-gel processing.The films present polycrystalline perovskite structure with a(100)preferred orientation by X-ray diffraction(XRD)analysis.The antiferroelectricity of the films is confirmed by the double hysteresis behaviors of polarization and double-bufferfly response of dielectric constant under the applied electrical field.Antiferroelectric properties and dielectric constant are improved while the polarization characteristic values are reduced with the increase of precursor solution concentration.The films at higher precursor solution concentration exhibit excellent dielectric properties.展开更多
Selective-controlled structure and shape of CeVO4 nanocrystals were successfully synthesized via a hydrothermal method from Na3VO4·12H2O and Ce（NO3）3·6H2O.The resulting products were characterized by X-ray...Selective-controlled structure and shape of CeVO4 nanocrystals were successfully synthesized via a hydrothermal method from Na3VO4·12H2O and Ce（NO3）3·6H2O.The resulting products were characterized by X-ray powder diffraction （XRD）,field emission scanning electron microscopy （FESEM） and energy dispersive spectroscopy （EDS）.The influence of hydrothermal temperature,precursor solution concentration on the crystal and morphology of products were further studied.The results showed that the as-synthesized products exhibited pure single-crystal CeVO4 nanoparticles with tetragonal structure.The hydrothermal temperature and precursor solution concentration had important effects on the formation of CeVO4 nanoparticles.Furthermore,the growth mechanism of CeVO4 nanoparticles was explained with Ostwald ripening mechanism.展开更多
We systematically investigated the development of film morphology and crystallinity of methyl-ammonium bismuth （Ⅲ） iodide （MA3Bi2I9） through one- step spin-coating on TiO2-deposited indium tin oxide （ITO）/glass...We systematically investigated the development of film morphology and crystallinity of methyl-ammonium bismuth （Ⅲ） iodide （MA3Bi2I9） through one- step spin-coating on TiO2-deposited indium tin oxide （ITO）/glass. The precursor solution concentration and substrate structure have been demonstrated to be critically important in the active-layer evolution of the MA3Bi2I9-based solar cell. This work successfully improved the cell efficiency to 0.42% （average： 0.38%） with the mesoscopic architecture of ITO/compact-TiOdmesoscopic-TiO2 （meso-TiO2）/ MA3Bi2I9/2,2＇,7,7＇-tetrakis（N,N-di-4-methoxyphenylamino）-9,9＇spiro-bifluorene （spiro-MeOTAD）/MoO3/Ag under a precursor concentration of 0.45 M, which provided the probability of further improving the efficiency of the BiB＋-based lead-free organic-inorganic hybrid solar cells.展开更多
文摘Epitaxial YBCO films were deposited on （100） LaAlO3 single-crystal substrates by metalorganic deposition of metal trifluoroacetate precursors with different concentrations. All the YBCO films have Tc around 91 K and Jc excess 2 MA/cm^2 at 77 K in zero field. XRD θ-2θscans show all the films have c-axis normal orientation. The FWHM （full width at half-maximum intensity） values of X-ray ω-scans of （005） reflection are 0.379°, 0.283°, and 0.543° for the YBCO thin films deposited with precursor solution concentrations of 1.52, 1.0, and 0.75 mol/L, respectively. With the concentration of the precursors decreasing, the thickness of the films decreases linearly. SEM micrographs show that porosities in the films become bigger with the precursor solution concentration decreasing. The big porosities in the film with the lowest concentration precursor deteriorate the superconducting property and make it have a wider superconducting transition and a lower Jc.
基金National Natural Science Foundation of China(No.60806039,No.51175483)China Postdoctoral Science Foundation Projects(No.20090461275,No.201003658)+1 种基金Shanxi Provincial Natural Science Foundation of China(No.20100210023-6)Shanxi Provincial Young Leaders on Science
文摘Pb0.97La0.02Zr0.95Ti0.05O3(PLZT)antiferroelectric thick films derived from different precursor solution concentrations are prepared on platinized silicon substrates by sol-gel processing.The films present polycrystalline perovskite structure with a(100)preferred orientation by X-ray diffraction(XRD)analysis.The antiferroelectricity of the films is confirmed by the double hysteresis behaviors of polarization and double-bufferfly response of dielectric constant under the applied electrical field.Antiferroelectric properties and dielectric constant are improved while the polarization characteristic values are reduced with the increase of precursor solution concentration.The films at higher precursor solution concentration exhibit excellent dielectric properties.
基金financial support by the Open Project Program of the State Key Laboratory of Solid Lu-brication, Lanzhou Institute of Chemical Physics,Chinese Academy of Sciences (0804)
文摘Selective-controlled structure and shape of CeVO4 nanocrystals were successfully synthesized via a hydrothermal method from Na3VO4·12H2O and Ce（NO3）3·6H2O.The resulting products were characterized by X-ray powder diffraction （XRD）,field emission scanning electron microscopy （FESEM） and energy dispersive spectroscopy （EDS）.The influence of hydrothermal temperature,precursor solution concentration on the crystal and morphology of products were further studied.The results showed that the as-synthesized products exhibited pure single-crystal CeVO4 nanoparticles with tetragonal structure.The hydrothermal temperature and precursor solution concentration had important effects on the formation of CeVO4 nanoparticles.Furthermore,the growth mechanism of CeVO4 nanoparticles was explained with Ostwald ripening mechanism.
基金This work was supported by the National Basic Research Program of China （No. 2014CB643503）, the National Natural Science Foundation of China （Nos. 91233114, 51373151 Zhejiang Province Natural LR15E030001）. and 51261130582） and Science Foundation （No.
文摘We systematically investigated the development of film morphology and crystallinity of methyl-ammonium bismuth （Ⅲ） iodide （MA3Bi2I9） through one- step spin-coating on TiO2-deposited indium tin oxide （ITO）/glass. The precursor solution concentration and substrate structure have been demonstrated to be critically important in the active-layer evolution of the MA3Bi2I9-based solar cell. This work successfully improved the cell efficiency to 0.42% （average： 0.38%） with the mesoscopic architecture of ITO/compact-TiOdmesoscopic-TiO2 （meso-TiO2）/ MA3Bi2I9/2,2＇,7,7＇-tetrakis（N,N-di-4-methoxyphenylamino）-9,9＇spiro-bifluorene （spiro-MeOTAD）/MoO3/Ag under a precursor concentration of 0.45 M, which provided the probability of further improving the efficiency of the BiB＋-based lead-free organic-inorganic hybrid solar cells.
