In situ monitoring of bare and K-doped Mo2C catalysts surface depassivation based on emission of electrons and K+ ions

• The method for in situ characterization of surface transformations on heterogeneous catalyst is described. The method is based on the measurements of thermal electron and ion emissions from the catalyst surface. It is demonstrated by investigating the depassivation process of undoped and K-doped Mo2C catalysts exposed to air after synthesis and use to identify characteristic steps of reduction-carburization by flowing CH4/H-2 gas mixture. The information obtained from thermal emission experiments is consistent with the methane consumption profile, which provided an independent observation of the recarburization step. (c) 2005 Published by Elsevier B.V.

Subject headings

NATURVETENSKAP  -- Kemi -- Fysikalisk kemi (hsv//swe)

NATURAL SCIENCES  -- Chemical Sciences -- Physical Chemistry (hsv//eng)

Keyword

Mo2C catalyst

depassivation

electron emission

work function

potassium desorption

in situ monitoring

MOLYBDENUM CARBIDE CATALYSTS

TRANSITION-METAL CARBIDES

MO2C/MO(100)

SURFACE

ATMOSPHERIC-PRESSURE

THERMIONIC EMISSION

DESORPTION-KINETICS

TUNGSTEN CARBIDES

AMMONIA-SYNTHESIS

REACTION

PATHWAYS

POTASSIUM

Publication and Content Type

ref (subject category)

art (subject category)