Spectral reconstruction of surface adsorbed species using band-target entropy minimization. Application to CO and NO reaction over a Pt/gamma-Al2O3 catalyst using in situ DRIFT spectroscopy.
The adsorption of NO and CO was studied on an alumina-supported platinum catalyst by in situ diffuse reflectance infrared Fourier-transform spectroscopy (DRIFTS). The temperature range was 50-160 degrees C and a wide variety of partial pressures was used. The band-target entropy minimization (BTEM) algorithm was applied to the DRIFTS data sets resulting in the pure component spectra of numerous species adsorbed on both the Pt (primarily a variety of Pt0-CO and Pt2+ -CO species) and alumina surface (i.e. nitrates, nitrites, bicarbonates, isocyanates) as well as gas-phase species. Thirty-one previously known species were identified as well as 6 new and previously unreported or previously unassigned spectra. The present results indicate that BTEM analysis of DRIFTS data is a very promising tool for the study of heterogeneous catalytic in situ spectroscopic data.
Institute of Chemical and Engineering Sciences, A*STAR (Agency for Science, Technology and Research), 1 Pesek Road, Jurong Island, Singapore627833.
Srilakshmi
S
Chilukoti
Effendi
E
Widjaja
Feng
F
Gao
Huajun
H
Zhang
Bruce G
BG
Anderson
J W Hans
JW
Niemantsverdriet
Marc
M
Garland