Reduction kinetics of NiO-MoO3 catalysts

Vagin, A. I.; Burmistrova, N. V.; Ерофеев, В. И.

doi:10.1007/bf02116757

Cited by 9 publications

(1 citation statement)

References 2 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Nickel–molybdenum composites are used to catalyze numerous redox reactions involving hydrogen intermediates. Examples include thermochemical processes like the water gas shift reaction, hydrotreating reactions, − and CO 2 methanation as well as electrochemical water splitting. − These catalysts are often generated via thermal reduction of mixed oxide precursors like nickel molybdate (NiMoO 4 ), and prior reports have shown that the details of precursor oxide preparation and thermal reduction have a major influence on the resulting catalytic activity. − Nonetheless, the specific details of how a competent Ni–Mo composite catalyst forms from oxide precursors has not been thoroughly explored. To address this knowledge gap, we report here a study involving the use of environmental transmission electron microscopy (ETEM) to directly observe the formation of a multiphase Ni–Mo composite catalyst from single-phase NiMoO 4 nanorods.…”

Section: Introductionmentioning

confidence: 99%

Direct Observation of Ni–Mo Bimetallic Catalyst Formation via Thermal Reduction of Nickel Molybdate Nanorods

et al. 2020

View full text Add to dashboard Cite

We used in situ environmental transmission electron microscopy to image the formation of a Ni−Mo composite nanocatalyst via thermal reduction of NiMoO 4 nanorods. Two clear structural changes were observed as the temperature was increased from 25 to 500 °C in the presence of H 2 (g): the first involved nucleation of nanoscale Ni-rich particles and the second involved general collapse of the remaining oxide phase along with substantial coarsening of the alloy particles. The activity of the catalyst toward alkaline hydrogen evolution was found to reach a maximum in a narrow range of reduction temperatures from 375 to 425 °C. This resulted in the formation of a mixed-phase product comprising sub-10 nm Ni 0.9 Mo 0.1 particles embedded in a porous Mo-rich oxide matrix. Thus, the most active Ni−Mo catalyst apparently requires intimate contact between the alloy component and the oxide phase, lending support to a catalytic mechanism involving metallic and oxidized surface sites.

show abstract