کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
5366026 1388342 2007 7 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Photoelectron spectroscopic investigation of transformation of trifluoroacetate precursors into superconducting YBa2Cu3O7−δ films
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی تئوریک و عملی
پیش نمایش صفحه اول مقاله
Photoelectron spectroscopic investigation of transformation of trifluoroacetate precursors into superconducting YBa2Cu3O7−δ films
چکیده انگلیسی

X-ray photoelectron spectroscopy (XPS) has been used to investigate the evolution of surface chemistry of YBa2Cu3O7−δ (Y123) films prepared by the metalorganic deposition (MOD) process using trifluoroacetate (TFA) precursors. Detailed XPS core-level spectra obtained from the samples quenched from various points during the calcining and firing stages have been reported for the first time and are used to identify surface species. The XPS data show evidence of formation of intermediate phases such as Y-O-F, BaF2, and CuO during the calcining process, which are the decomposition products of yttrium, barium, and copper trifluoroacetates, respectively. The TFA precursors are completely decomposed at the end of calcination. The change of binding energies for Y 3d5/2, Ba 3d5/2, and O 1s during the firing process indicates that Y123 starts to form at 800 °C after 0.5 h firing. Based on the experimental results, an alternative mechanism of the chemical evolution from precursor to final film in the TFA-MOD process is proposed.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Applied Surface Science - Volume 253, Issue 10, 15 March 2007, Pages 4652-4658
نویسندگان
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