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Title: An x-ray absorption spectroscopy study of Mo oxidation in Pb at elevated temperatures

Abstract

The corrosion of fuel cladding and structural materials by lead and lead-bismuth eutectic in the liquid state at elevated temperatures is an issue that must be considered when designing advanced nuclear systems and high-power spallation neutron targets. In this work, lead corrosion studies of molybdenum were performed to investigate the interaction layer as a function of temperature by X-ray absorption spectroscopy. In situ X-ray absorption measurements on a Mo substrate with a 3-6 {micro}m layer of Pb deposited by thermal evaporation were performed at temperatures up to 900 C and at a 15{sup o} angle to the incident X-rays. The changes in the local atomic structure of the corrosion layer are visible in the difference extended X-ray absorption fine structure and the linear combination fitting of the X-ray absorption near-edge structure to as-deposited molybdenum sample and molybdenum oxide (MoO{sub 2} and MoO{sub 3}) standards. The data are consistent with the appearance of MoO{sub 3} in an intermediate temperature range (650-800 C) and the more stable MoO{sub 2} phase dominating at high and low temperatures.

Authors:
; ; ; ;  [1]
  1. (
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1005708
Resource Type:
Journal Article
Resource Relation:
Journal Name: J. Nucl. Mater.; Journal Volume: 392; Journal Issue: (2) ; 07, 2009; Conference: Anaheim, CA
Country of Publication:
United States
Language:
ENGLISH
Subject:
11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS; ABSORPTION; ABSORPTION SPECTROSCOPY; ACCIDENTS; BISMUTH; CLADDING; CORROSION; EUTECTICS; EVAPORATION; FINE STRUCTURE; FUELS; FUNCTIONS; INTERACTIONS; LAYERS; LEAD; LIQUIDS; MOLYBDENUM; MOLYBDENUM OXIDES; NEUTRONS; NUCLEAR FUELS; OXIDATION; REACTORS; SPALLATION; SUBSTRATES; TEMPERATURE RANGE; TEMPERATURE RANGE 0065-0273 K

Citation Formats

Liu, Shanshan, Olive, Daniel, Terry, Jeff, Segre, Carlo U., and IIT). An x-ray absorption spectroscopy study of Mo oxidation in Pb at elevated temperatures. United States: N. p., 2009. Web. doi:10.1016/j.jnucmat.2009.03.005.
Liu, Shanshan, Olive, Daniel, Terry, Jeff, Segre, Carlo U., & IIT). An x-ray absorption spectroscopy study of Mo oxidation in Pb at elevated temperatures. United States. doi:10.1016/j.jnucmat.2009.03.005.
Liu, Shanshan, Olive, Daniel, Terry, Jeff, Segre, Carlo U., and IIT). Tue . "An x-ray absorption spectroscopy study of Mo oxidation in Pb at elevated temperatures". United States. doi:10.1016/j.jnucmat.2009.03.005.
@article{osti_1005708,
title = {An x-ray absorption spectroscopy study of Mo oxidation in Pb at elevated temperatures},
author = {Liu, Shanshan and Olive, Daniel and Terry, Jeff and Segre, Carlo U. and IIT)},
abstractNote = {The corrosion of fuel cladding and structural materials by lead and lead-bismuth eutectic in the liquid state at elevated temperatures is an issue that must be considered when designing advanced nuclear systems and high-power spallation neutron targets. In this work, lead corrosion studies of molybdenum were performed to investigate the interaction layer as a function of temperature by X-ray absorption spectroscopy. In situ X-ray absorption measurements on a Mo substrate with a 3-6 {micro}m layer of Pb deposited by thermal evaporation were performed at temperatures up to 900 C and at a 15{sup o} angle to the incident X-rays. The changes in the local atomic structure of the corrosion layer are visible in the difference extended X-ray absorption fine structure and the linear combination fitting of the X-ray absorption near-edge structure to as-deposited molybdenum sample and molybdenum oxide (MoO{sub 2} and MoO{sub 3}) standards. The data are consistent with the appearance of MoO{sub 3} in an intermediate temperature range (650-800 C) and the more stable MoO{sub 2} phase dominating at high and low temperatures.},
doi = {10.1016/j.jnucmat.2009.03.005},
journal = {J. Nucl. Mater.},
number = (2) ; 07, 2009,
volume = 392,
place = {United States},
year = {Tue Jun 30 00:00:00 EDT 2009},
month = {Tue Jun 30 00:00:00 EDT 2009}
}
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  • No abstract prepared.
  • The nature of the surface formed by a saturated layer ({Theta}(NO) = 1.0) of NO on a Mo(100) surface at 150 K has been determined by using both angle-resolved ultraviolet photoelectron spectroscopy and the angular variation of near-edge x-ray absorption fine structure (NEXAFS). Photoelectron spectroscopy indicates that NO can adsorb molecularly at this temperature but that a portion of the NO is also dissociated, even at 150 K. The orientation of the molecular species is measured by using both photoelectron spectroscopy and NEXAFS. Both techniques yield identical geometries, indicating that chemisorbed NO has a molecular axis that is tilted atmore » 35{degree} {plus minus} 5{degree} with respect to the surface normal.« less