Vibrational Analysis of H2 and D2 Adsorption on Pt/SiO2
Journal article, 2005

Vibrational properties of surface species formed upon H2 and D2 exposure of silica supported platinum particles have been investigated with in situ diffuse reflection infrared Fourier transform spectroscopy. Experiments have been performed at 50-250 degrees C, using different platinum loading of the samples in the absence and presence of oxygen. In addition, electronic structure calculations and vibrational analysis have been performed within the density functional theory for H adsorption on a silica cluster, (HO)(3)SiOSi(OH)(3). The spectroscopy experiments showed reversible formation of isolated OH and OD groups on the silica surface when the samples were exposed to H2 and D2, respectively. In addition to the absorption peak corresponding to isolated OH and OD groups, an intense broad band was observed around 3270 cm(-1) (2500 cm(-1)) during H2 (D2) exposure. Supported by the calculations, this band was assigned to perturbed OH groups on the silica surface. The surface coverage of new OH groups was found to correlate to the platinum loading in the samples, indicating that the new silanol groups were formed in the vicinity of the Pt particles. In the investigated temperature interval, the formation rate of CH groups was not found to be temperature dependent.

SILICA

1ST-PRINCIPLES CALCULATIONS

HYDROXYL-GROUPS

SURFACE

MOLECULES

AEROSIL

CHEMICAL SENSORS

SPILT-OVER HYDROGEN

FIELD-EFFECT DEVICES

SIO2

Author

Mikaela Wallin

Competence Centre for Catalysis (KCK)

Chalmers, Chemical and Biological Engineering

Henrik Grönbeck

Chalmers, Applied Physics, Chemical Physics

Competence Centre for Catalysis (KCK)

A. Lloyd Spetz

Linköping University

Mats Eriksson

Linköping University

Magnus Skoglundh

Chalmers, Chemical and Biological Engineering

Competence Centre for Catalysis (KCK)

Journal of Physical Chemistry B

1520-6106 (ISSN) 1520-5207 (eISSN)

Vol. 109 19 9581-9588

Driving Forces

Sustainable development

Areas of Advance

Nanoscience and Nanotechnology (2010-2017)

Transport

Energy

Materials Science

Subject Categories

Physical Sciences

Chemical Engineering

DOI

10.1021/jp044759z

More information

Latest update

2/28/2018