Magnesium-Modified Co3O4 Catalyst with Remarkable Performance for Toluene Low Temperature Deep Oxidation

Abstract

Co3O4, MgCo2O4 and MgO materials have been synthesized using a simple co-precipitation approach and systematically characterized. The total conversion of toluene to CO2 and H2O over spinel MgCo2O4 with wormlike morphology has been investigated. Compared with single metal oxides (Co3O4 and MgO), MgCo2O4 with the highest activity has exhibited almost 100% oxidation of toluene at 255 °C. The obtained results are analogous to typical precious metal supported catalysts. The activation energy of toluene over MgCo2O4 (38.5 kJ/mol) is found to be much lower than that of Co3O4 (68.9 kJ/mol) and MgO ((87.8 kJ/mol)). Compared with the single Co and Mg metal oxide, the as-prepared spinel MgCo2O4 exhibits a larger surface area, highest absorbed oxygen and more oxygen vacancies, thus highest mobility of oxygen species due to its good redox capability. Furthermore, the samples specific surface area, low-temperature reducibility and surface adsorbed oxygenated species ratio decreased as follows: MgCo2O4 > Co3O4 > MgO; which is completely in line with the catalytic performance trends and constitute the reasons for MgCo2O4 high excellent activity towards toluene total oxidation. The overall finding supported by ab initio molecular dynamics simulations of toluene oxidation on the Co3O4 and MgCo2O4 suggest that the catalytic process follows a Mars–van Krevelen mechanism.

Copper and iron co-doping effects on the structure, optical energy band gap, and catalytic behaviour of Co3O4 nanocrystals towards low-temperature total oxidation of toluene

“…4,5 Presently, two varieties of catalysts have been established for the total conversion of toluene,, namely supported noble metals (Ag, Au, Pt and Pd) [6][7][8][9] and metal oxides. [10][11][12][13][14][15] Particularly, Transition metal oxides (TMOs) especially possesses the advantages of availability, low cost, high thermal stability, considerable reducibility, strong resistance to poisons and promising catalytic performance. [16][17][18] Therefore, TMOs have received much attention in the total abatement of VOCs.…”

“…Recently, extensive practical and theoretical investigation on the influence of transition metal cation dopant features on the physicochemical and redox properties of cobalt-based binary oxide catalysts have been reported. 10,14 The authors have established that, doping could redesign chemical composition and ionic states, ionic radius, as well as chemical bonding in the bulk and surface of Co3O4, which in consequence might give rise to an excellent catalytic performance.…”

Magnesium Cobaltite Embedded in Corncob-Derived Nitrogen-Doped Carbon as a Cathode Catalyst for Power Generation in Microbial Fuel Cells

“…The Mg/NC-700 catalyst shows no peak, confirming that Mg does not account for the catalytic activity. Of importance, the substitution of Mg for Co ions is favorable for the MgCo 2 O 4 /NC-700 catalyst to achieve high oxygen reduction potential and limiting current density, thus benefitting ORR activity over single Co and Mg metal oxide materials Figure a shows the CV curves for Mg/NC-700, Co/NC-700, and MgCo 2 O 4 /NC-700.…”

2-Propanol Interacting with Co3O4(001):A combined AIMD and vSFS study

“…The PBE functional 27 was utilized to treat exchange and correlation e↵ects, and a U correction of the Hubbard 28 type was added to achieve a correct description of Co 3d states. The value of U which was taken from our previous studies 24,[29][30][31][32][33] and set to 2 eV. In order to take into account the dispersion interactions, specifically in the water films, the Grimme D3 correction was added to the PBE exchange-correlation functional.…”