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Structural, surface and catalytic properties of pure and ZrO 2 ‐doped nanosized cobalt‐manganese mixed oxides
Author(s) -
Ibrahim Shaimaa M.,
Badawy Abdelrahman A.,
ElShobaky Gamil A.,
Mohamed Heba A.
Publication year - 2014
Publication title -
the canadian journal of chemical engineering
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.404
H-Index - 67
eISSN - 1939-019X
pISSN - 0008-4034
DOI - 10.1002/cjce.21916
Subject(s) - calcination , manganese , cobalt , dopant , catalysis , materials science , doping , inorganic chemistry , phase (matter) , adsorption , specific surface area , chemical engineering , chemistry , metallurgy , organic chemistry , optoelectronics , engineering
The role of ZrO 2 ‐doping of CoO–Mn 2 O 3 system on its structural, surface and catalytic properties was studied using XRD, EDX, nitrogen adsorption at −196°C and H 2 O 2 ‐decomposition at 30–50°C. The results revealed that all solids calcined at 300–500°C consisted of nanosized Co 2 MnO 4 as a major phase together with Co 3 O 4 phase. The surface and bulk compositions of pure and variously doped solids were completely different from each other's. The concentration of surface manganese species was much higher than that of cobalt. The addition of the smallest amount of ZrO 2 (0.75 mol%) much increased the surface concentration of manganese species. The increase of calcination temperature of all solids increased progressively the catalytic activity which increased by doping with the smallest amount of ZrO 2 then decreased by doping with further amounts of ZrO 2 dopant falling to values smaller than that measured for pure sample.