TY - JOUR

T1 - Highly efficient cobalt-modified hopcalite catalysts prepared through crednerite-spinel transformation

AU - Svintsitskiy, D. A.

AU - Kvasova, E. S.

AU - Kardash, T. Yu

AU - Sokovikov, N. A.

AU - Stonkus, O. A.

AU - Boronin, A. I.

PY - 2025/1/17

Y1 - 2025/1/17

N2 - The work presents a study and comparison of the catalytic properties of hopcalite catalysts composed of copper-manganese and copper-cobalt-manganese spinel particles in the low-temperature CO oxidation reaction. The cubic spinel structure was formed immediately under reaction conditions through the transformation of hydrothermally prepared crednerite CuMn(Co)O2 particles. Both the initial crednerite-type and the resultant spinel-type particles (Cu, Mn, Co)3O4 exhibited a lamellar morphology and a uniform distribution of elements throughout their bulk and surface. It was found that the modification of the copper-manganese oxide with cobalt resulted in increased particle dispersion and a significant distortion of the crednerite crystal lattice. As a result, this modification reduced the temperature required for the crednerite-to-spinel transformation to 250 °C, whereas the unmodified catalyst is transformed after heating to 350-400 °C only. Furthermore, it was demonstrated that during the CO oxidation at room temperature, the modified spinel particles (Cu, Mn, Co)3O4 exhibited a specific catalytic activity ∼3.5 times greater than that of the copper-manganese system. This enhancement is associated with the stabilization of a more oxidized surface state for the modified spinel particles, which may involve an increased contribution of Co3+ and Mn4+ surface species, as well as an enhancement in the overall lattice oxygen mobility.

AB - The work presents a study and comparison of the catalytic properties of hopcalite catalysts composed of copper-manganese and copper-cobalt-manganese spinel particles in the low-temperature CO oxidation reaction. The cubic spinel structure was formed immediately under reaction conditions through the transformation of hydrothermally prepared crednerite CuMn(Co)O2 particles. Both the initial crednerite-type and the resultant spinel-type particles (Cu, Mn, Co)3O4 exhibited a lamellar morphology and a uniform distribution of elements throughout their bulk and surface. It was found that the modification of the copper-manganese oxide with cobalt resulted in increased particle dispersion and a significant distortion of the crednerite crystal lattice. As a result, this modification reduced the temperature required for the crednerite-to-spinel transformation to 250 °C, whereas the unmodified catalyst is transformed after heating to 350-400 °C only. Furthermore, it was demonstrated that during the CO oxidation at room temperature, the modified spinel particles (Cu, Mn, Co)3O4 exhibited a specific catalytic activity ∼3.5 times greater than that of the copper-manganese system. This enhancement is associated with the stabilization of a more oxidized surface state for the modified spinel particles, which may involve an increased contribution of Co3+ and Mn4+ surface species, as well as an enhancement in the overall lattice oxygen mobility.

KW - Bioremediation

KW - Cobalt

KW - Cobalt metallography

KW - Cobalt metallurgy

KW - Crystal lattices

KW - Manganese oxide

KW - Catalytic properties

KW - Cubic spinel structure

KW - Hopcalite catalysts

KW - Hydrothermally

KW - Low-temperature CO oxidation

KW - Manganese spinels

KW - Oxidation reactions

KW - Reaction conditions

KW - Spinel particles

KW - Spinel-type

KW - Catalytic oxidation

UR - https://www.mendeley.com/catalogue/ef32f4f1-4115-3b97-8f6d-747b5182d305/

UR - https://www.scopus.com/record/display.uri?eid=2-s2.0-85216762747&origin=inward&txGid=34307dc974dfff302e3879aaaacc0e65

U2 - 10.1039/d4re00552j

DO - 10.1039/d4re00552j

M3 - Article

JO - Reaction Chemistry and Engineering

JF - Reaction Chemistry and Engineering

SN - 2058-9883

ER -