This article focused on the phase transition mechanism of LaNiO3 with a perovskite structure during the hot sintering process,which was observed and analyzed by ex-situ and in-situ electron microscopy combined with a macroscopic spectroscopy.The experimental result indicated that the precursor fibers of PVP/PAN/Ni(NO3)2/La(NO3)3 prepared by electrospinning formed a LaNiO3 perovskite structure.Under the high-temperature sintering,the carbon polymer matrix was continuously decomposed during the crystal growth process.The metal ions immersed in the polymer matrix were heated and combined with oxygen in the atmosphere to form oxide crystal embryos,showing a typical Ostwald ripening growth process.At about 600 ℃,the LaNiO3 crystal phase was generated.With the further increase of temperature,the grains fused with each other to form one-dimensional LaNiO3 nanowires stacked with nanoparticles.The experiment revealed the micro growth mechanism of LaNiO3 nanowires,providing ideas for the growth regulation and performance modification of materials.
关键词
钙钛矿结构/物相转变/奥斯瓦尔德熟化生长/原位电子显微学
Key words
perovskite structure/phase transition/Oswald ripening mechanism/in-situ electron microscopy
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