Elementally Resolved Imaging of Dynamic Surface Processes: Chemical Waves in the SystemRh(110)/NO+H2

Spectroscopic methods enabling real-time monitoring of dynamic surface processes are a prerequisite for identifying how a catalyst triggers a chemical reaction. We present an in situ photoluminescence spectroscopy approach for probing the thermo-catalytic 2-propanol oxidation over mesostructured Co3O4 nanowires. Under oxidative conditions, a distinct blue emission at ~420 nm is detected that increases with temperature up to 280 °C, with an intermediate maximum at 150 °C. Catalytic data gained under comparable conditions show that this course of photoluminescence intensity precisely follows the conversion of 2-propanol and the production of acetone. The blue emission is assigned to the radiative recombination of unbound acetone molecules, the n - π* transition of which is selectively excited by a wavelength of 270 nm. These findings open a pathway for studying thermo-catalytic processes via in situ photoluminescence spectroscopy thereby gaining information about the performance of the catalyst and the formation of intermediate products.

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EnergyDispersed NearEdge XRay Absorption Fine Structure a New Technique to Study Dynamic Surface Processes

Physica Scripta ◽

10.1238/physica.topical.115a00088 ◽

2005 ◽

pp. 88

Author(s):

H. Kondoh ◽

K. Amemiya ◽

I. Nakai ◽

M. Nagasaka ◽

A. Nambu ◽

...

Keyword(s):

Fine Structure ◽

Surface Processes ◽

New Technique ◽

Dynamic Surface ◽

Absorption Fine ◽

A New Technique

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Real-Time Optical Diagnostics For Measuring And Controlling Epitaxial Growth

MRS Proceedings ◽

10.1557/proc-222-63 ◽

1991 ◽

Vol 222 ◽

Cited By ~ 3

Author(s):

D. E. Aspnes ◽

R. Bhat ◽

E. Colas ◽

L. T. Florez ◽

S. Gregory ◽

...

Keyword(s):

Molecular Beam ◽

Chemical Vapor ◽

Optical Methods ◽

Surface Processes ◽

Microstructural Properties ◽

Difference Spectroscopy ◽

Semiconductor Crystal ◽

Dynamic Surface ◽

Control Growth ◽

Reflectance Difference Spectroscopy

ABSTRACTA variety of optical methods are now available for studying surface processes and for monitoring layer thicknesses and compositions during semiconductor crystal growth by molecular beam epitaxy (MBE), organometallic chemical vapor deposition (OMCVD), and related techniques. New capabilities for surface analysis are being provided by developing techniques such as reflectance-difference spectroscopy (RDS), which use intrinsic symmetries to suppress ordinarily dominant bulk contributions. Bulk and microstructural properties such as compositions and layer thicknesses can be determined by techniques such as spectroellipsometry (SE), which return information integrated over the penetration depth of light. Recent advances include the application of reflectance to monitor dynamic surface processes, RDS to characterize (001) GaAs surfaces in OMCVD environments, and SE to control growth of AlxGa1-x, As materials and structures.

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Chemical Specific Imaging and Spectroscopy of Interfaces and Dynamic Surface Processes with Synchrotron-Based X-ray Microscopy

e-Journal of Surface Science and Nanotechnology ◽

10.1380/ejssnt.2004.1 ◽

2004 ◽

Vol 2 ◽

pp. 1-7 ◽

Cited By ~ 1

Author(s):

Maya Kiskinova

Keyword(s):

Surface Processes ◽

Dynamic Surface ◽

X Ray ◽

Imaging And Spectroscopy

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