Catalytic reduction of NO2 with hydrogen on Pt field emitter tips: kinetic instabilities on the nanoscale

Langmuir. 2010 Nov 2;26(21):16381-91. doi: 10.1021/la102003x.

Abstract

The catalytic reduction of NO(2) with hydrogen on a Pt field emitter tip is investigated using both field electron microscopy (FEM) and field ion microscopy (FIM). A rich variety of nonlinear behavior and unusually high catalytic activity around the {012} facets are observed. Our FEM investigations reveal that the correlation function exhibits damped oscillations with a decaying envelope, showing that molecular noise will influence the dynamics of the oscillations. The dependence of the oscillatory period on the P(H(2))/P(NO(2)) pressure ratios is analyzed. Similar patterns are reported under FIM conditions. Corresponding density functional theory (DFT) calculations for the adsorption of NO(2) on Pt{012} in the presence of an external electric field are performed in order to gain an atomistic understanding of the underlying nonlinear phenomena.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adsorption
  • Catalysis
  • Hydrogen / chemistry*
  • Kinetics
  • Metal Nanoparticles / chemistry*
  • Microscopy, Electron
  • Nitrogen Dioxide / chemistry*
  • Oxidation-Reduction
  • Particle Size
  • Platinum / chemistry*
  • Surface Properties

Substances

  • Platinum
  • Hydrogen
  • Nitrogen Dioxide