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利用扫描隧道显微镜(STM)和X射线光电子能谱(XPS)对Pt(111)表面制备的Fe单层薄膜及其在不同环境气氛条件下的多种结构进行了研究.在温度为487K的Pt(111)表面制备出了完整的Fe单层薄膜Fe/Pt(111).对Fe/Pt(111)依次升高温度进行超高真空退火,STM和XPS结果表明退火温度高于800K时,表面Fe原子扩散到次表层区域,形成次表层Fe结构Pt/Fe/Pt(111).Pt/Fe/Pt(111)在O2氧化气氛中经850K退火可转变成表面FeO薄膜FeO/Pt(111).FeO/Pt(111)结构在温和的H2还原气氛中(600K)转变成表面Fe结构,进一步的还原处理(800K)则可以重新生成Pt/Fe/Pt(111).控制样品的环境气氛在O2和H2之间切换,使得表面Fe(FeO)和次表面Fe可以重复地转变.本研究实现了多种Fe-Pt表面结构的可控制备,可为合理地设计高效、价廉的催化剂提供借鉴.
The Fe single-layer thin films prepared on the surface of Pt (111) and its various structures under different ambient atmosphere conditions were studied by scanning tunneling microscope (STM) and X-ray photoelectron spectroscopy (XPS) (111), a complete Fe monolayer thin film Fe / Pt (111) was prepared on the surface of Fe (111) .The results of STM and XPS showed that the surface of Fe / Pt Fe atom diffused into the subsurface region to form subsurface Fe structure Pt / Fe / Pt (111) .Pt / Fe / Pt (111) The FeO / Pt (111) structure was transformed into a surface Fe structure in a mild H2 reduction atmosphere (600K), and Pt / Fe / Pt (111) could be regenerated by further reduction treatment The switching between O2 and H2 makes the surface Fe (FeO) and subsurface Fe can be repeatedly changed.This study has achieved a variety of Fe-Pt surface structure controllable preparation, which can provide a reasonable design for high efficiency, low cost catalyst Learn from