採用脈衝雷射沉積法，以LaAlO3 (001) 單晶為基底，製備了GdFeO3型SNO薄膜。XRD結果顯示，SNO薄膜具有單晶和光滑表面，晶粒朝向沿c軸排列。
Fig. 1. (a) The XRD pattern of SNO on LAO and (b) an expanded view showing the (002)SNOand (002)LAO peaks. The inset of (b) shows the X-ray reflectivity; (c) φ scans of LAO(111) (red line) and SNO(113) (blue line), the inset shows the rocking curve of the SNO(113) peak with a FWHM of 0.34°; (d) is an AFM image of an SNO thin film surface.
在空氣中873K熱處理後，薄膜在373K時，表現出金屬態向絕緣態轉變的現象。
Fig. 2. The temperature dependence of the resistance of SNO in air; (a) the resistance on cycle 1 (heating) and the 1st derivative, (b) the resistance of cycle 4 (cooling), the FFT smoothed |dR/dT| vs. temperature shows the Metal-Insulator Transition Temperature at 373 K. The inset of (b) shows the resistance over the whole temperature range on cooling.
電化學阻抗測試表明，SNO薄膜在氫氣環境中，具有較高的離子傳導率(0.030 S/cm 在 773 K)。質子傳導活化能在473–773 K 時為0.23 eV ，在773–973 K時為0.37 eV 。
Fig. 4. An Electrochemical Impedance spectrum of H-SNO and the fitting results at 971 K in 3%H2 gas, the inset is the equivalent circuit. (b) an Arrhenius plot of the conductivity from the fitted data and the activation energy. Data from Ref. R [9]. for a SNO film on LAO prepared by magnetron sputtering are shown for comparison.
SmNiO3(SNO) epitaxial thin films were grown on (001) LaAlO3 substrates.
A Metal-Insulator-Transition occurs at 373 K for the films after annealing at 873 K in air.
EIS studies indicate that the SNO films have a high ionic conductivity (0.030 S/cm at 773 K) in a hydrogen atmosphere.
The activation energy for proton conductivity was determined to be 0.23 eV at 473–773 K and 0.37 eV at 773–973 K respectively.
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Dr. Xu Xing is a postdoc fellow in Tsinghua University. He received his PhD in Physics from University of Texas at San Antonio (UTSA) in Aug 2015.
Miss Chen Liu was a master student at the School of Materials Science and Engineering, Tsinghua University. She received her master degree in June 2018.
Dr. Jing Ma is an assistant professor in School of Materials Science and Engineering, Tsinghua University. She received her B.S. and Ph.D degree in materials science and engineering from Tsinghua University in 2006 and 2011 respectively, and completed post-doc period in Stockholm University from 2012 to 2013. Her research interests include high performance multiferroic magnetoelectric composites and device prototypes, and functional oxide films.
Dr. Allan Jacobson is Robert A. Welch Chair of Science Professor in University of Houston. He is Director of the Texas Center for Superconductivity at UH. He is a fellow of National Academy of Inventors, US Editor of Solid State Ionics, Associate Editor of Materials Research Bulletin and on Editorial Advisory Board of Progress in Solid State Chemistry, Journal of Solid State Chemistry and Solid State Sciences. He received his PhD in from Oxford in 1969.
Dr. Cewen Nan is Academician of the Chinese Academy of Sciences, Cheung-Kong Professor, Tsinghua University, China. He received his PhD degree from Wuhan University of Technology in 1992.
Dr. Chonglin Chen is currently a professor of physics in the Department of Physics and Astronomy, University of Texas at San Antonio, a joint professor at the Texas Center for Superconductivity at the University of Houston (TcSUH), the 「Thousand Talent Program - B″ professor at Tsinghua University, and the fellow of the American Ceramics Society. He received his PhD degree in solid state science (Materials) from the Pennsylvania State University in 1994.