Local structure of Pt and Pd ions in Ce(1-x)TixO2: x-ray diffraction, x-ray photoelectron spectroscopy, and extended x-ray absorption fine structure.

نویسندگان

  • Tinku Baidya
  • K R Priolkar
  • P R Sarode
  • M S Hegde
  • K Asakura
  • G Tateno
  • Y Koike
چکیده

Ce(1-x-y)Ti(x)Pt(y)O(2-delta) (x=0.15; y=0.01) and Ce(1-x-y)Ti(x)Pd(y)O(2-delta) (x=0.25; y=0.02 and 0.05) are found to be good CO oxidation catalysts [T. Baidya et al., J. Phys. Chem. B 110, 5262 (2006); T. Baidya et al., J. Phys. Chem. C 111, 830 (2007)]. A detailed structural study of these compounds has been carried out by extended x-ray absorption fine structure along with x-ray diffraction and x-ray photoelectron spectroscopy. The gross cubic fluorite structure of CeO(2) is retained in the mixed oxides. Oxide ion sublattice around Ti as well as Pt and Pd ions is destabilized in the solid solution. Instead of ideal eight coordinations, Ti, Pd, and Pt ions have 4+3, 4+3, and 3+4 coordinations creating long and short bonds. The long Ti-O, Pd-O, and Pt-O bonds are approximately 2.47 A (2.63 A for Pt-O) which are much higher than average Ce-O bonds of 2.34 A.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

A dispenser-reactor apparatus applied for in situ XAS monitoring of Pt nanoparticle formation.

In situ time-resolved X-ray absorption spectroscopy (XAS) measurements collected at the Pt L3-edge during the synthesis of Pt nanoparticles (NPs) in aqueous solution are reported. A specially designed dispenser-reactor apparatus allowed for monitoring changes in the XAS spectra from the earliest moments of Pt ions in solution until the formation of metallic nanoparticles with a mean diameter of...

متن کامل

Preparation of Fe Substituted ZnO Nanoparticles and Investigation of Their Magnetic Behaviors

Nano-powders of diluted magnetic semiconductor Zn1-xFexO (0.0≤ x ≤0.1) were prepared via the sol-gel auto-combustion method. Crystal structure and phase identification carried out by X-Ray Diffraction (XRD) analysis. Mean crystallite size of the powders was estimated by Scherrer's formula. As M-H loops of the Fe substituted ZnO showed ferromagnetic behavior. The result...

متن کامل

In-situ extended X-ray absorption fine structure study of electrostriction in Gd doped ceria

Articles you may be interested in Local structure and polarization resistance of Ce doped SrMnO3 using extended x-ray fine structure analysis Appl. Phosphorus-doped silicon nanowires studied by near edge x-ray absorption fine structure spectroscopy Appl. Fully relativistic theory for the magnetic extended x-ray absorption fine structure

متن کامل

ساخت و بررسی ویژگی‌های ساختاری، مغناطیسی و جذب مایکروویو فریت باریم آلایش یافته با سریوم

In this study the structure, magnetic and microwave absorption properties of cerium (Ce) doped barium hexaferrite with general formulae BaCexFe12-xO19 (x=0.0, 0.05, 0.1, 0.15, 0.2) have been investigated. These samples have been prepared by sol- gel method. Influence of replacing Fe+3 ion by rare- earth Ce+3 ion on the structural, magnetic and microwave absorption properties have been investiga...

متن کامل

Selective deposition of Pt onto supported metal clusters for fuel cell electrocatalysts.

We report a new method for deposition of Pt on a metal core to develop real electrocatalysts with significantly reduced amounts of expensive Pt as well as enhanced activity for oxygen reduction reaction. Ru and Pd have different crystal structures and modify the electronic structure of Pt to a different extent (shifts in d-band center). They were chosen as core materials to examine whether hydr...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:
  • The Journal of chemical physics

دوره 128 12  شماره 

صفحات  -

تاریخ انتشار 2008