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In The Name Of God. X-ray Photoelectron Spectroscopy Instrumental & Application. K.Azadkish H. Asadi M.N.Amiri S.Amininasab E.Bahjati H.Hamidi A.R.Jafari M.J.Hosseinishahi Dastjerdi *. X-ray Photoelectron Spectroscopy Instrumental & Application 2014/04/06. کاربرد و دستگاهوری
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X-ray Photoelectron Spectroscopy Instrumental & Application K.Azadkish H. Asadi M.N.Amiri S.Amininasab E.Bahjati H.Hamidi A.R.Jafari M.J.Hosseinishahi Dastjerdi*
X-ray Photoelectron Spectroscopy Instrumental & Application 2014/04/06 کاربرد و دستگاهوری طیف بینی فوتوالکترون اشعه ی ایکس 1393/01/17 K.Azadkish H. Asadi M.N.Amiri S.Amininasab E.Bahjati A.R.Jafari H.Hamidi M.J.Hosseinishahi Dastjerdi* کمال آزادکیش حسین اسدی محمد نبی امیری سعید امینی نسب اسماعیل بهجتی احمد رضا جعفری هادی حمیدی محمد جواد حسینی شاهی دستجردی*
Introduction Instrumental Application XPS Comparison with other techniques Conclusion 1
Introduction XPS K. Siegbahn Received the 1981 Nobel Prize in Physics for his work 2 Re: Douglas A. Skoog, F James Holler, Stanley R. Crouch/ Principles of Instrumental Analysis / Sixth edition
Introduction What is XPS? Principles of XPS 3 Re: www.surfaceanalysis.org
Introduction Incident X-ray Free Electron Level Conduction Band Fermi Level Valence Band 2p L2,L3 2s L1 1s K 4 Re: Siegbahn, K.; Edvarson, K. I. Al (1956). "β-Ray spectroscopy in the precision range of 1 : 1e6". Nuclear Physics
Introduction Work function Binding energy of the electron The kinetic energy of the emitted electron 5 Re: Siegbahn, K.; Edvarson, K. I. Al (1956). "β-Ray spectroscopy in the precision range of 1 : 1e6". Nuclear Physics
Instrumental Hemispherical capacitor Multichannel transducer Lens Multichannel analyzer Out put display 7 Re: Douglas A. Skoog, F James Holler, Stanley R. Crouch/ Principles of Instrumental Analysis / Sixth edition
XPS Comparison with other techniques 9 Re: Surface Sensitive Technique
Conclusion • One of the most important applications of XPS has been the identification of oxidation states of elements in inorganic compounds • XPS provides information about not only the atomic composition of a sample but also the structure and oxidation state of the compounds being examined. • XPS is used from starting Li(A>=3) because of smaller orbital’s radius and analysis of organic compounds cannot be done with XPS because of degredation with radiation 10
Conclusion • Spectra are a plot of detected electron current (Intensity) vs KE (plotted as BE). • Peaks occur at characteristic BEs. • Survey scan gives information about the elements present; it is a plot of intensity over a wide BEs at low instrumental resolution. • Narrow scans at high instrumental resolution are often used for – more quantitative estimate of the composition (from peak areas) – Chemical states of the different elements on the surface. • – Relative intensity measurements can provide information about the thickness of an over layer. 11