Catalysis

Adsorption

Valence (chemistry)

Catalytic combustion

Engineering

Mesoporous material

Metallurgy

Materials science

Thermal desorption spectroscopy

Acoustics

Inorganic chemistry

Chemical engineering

Nitrogen

Lattice (music)

Toluene

Porosity

Physical chemistry

Physics

Organic chemistry

Oxygen

Manganese

X-ray photoelectron spectroscopy

Combustion

Desorption

Composite material

Chemistry

Mineralization (soil science)

Specific surface area

Applied Surface Science

To elucidate the role of high valence manganese and surface lattice oxygen in catalyst for catalytic combustion of toluene, herein, a porous LaMnO3 catalyst was firstly fabricated using ordered mesoporous carbon (OMC) as a hard-template. Compared with pristine LaMnO3-bulk, the optimal porous LaMnO3 exhibited boosted catalytic performance for toluene combustion, leading to a ∼50 ℃ lower T90% (required temperatures for 90% toluene conversions). The results of N2 adsorption–desorption measurement, X-ray photoelectron spectroscope, O2 temperature-programmed desorption and H2 temperature-programmed reduction indicated that the optimal porous LaMnO3 displayed high molar ratios of surface Mn4+/Mn3+ and Olatt/Oads, which exposed abundant active sites and promoted the preferential low-temperature catalytic oxidation of toluene. Simultaneously, the increased content of high valence manganese (Mn4+) and surface lattice oxygen (Olatt) in porous LaMnO3 catalyst accelerated the cycle of toluene deep oxidation. Combined with the analysis of toluene intermediates by in situ diffuse reflectance infrared Fourier transform spectroscopy, the toluene degradation mechanism over porous LaMnO3 was also explored. This work provides a feasible strategy for design of porous Mn-based perovskite catalyst with a high efficiency and stability for catalytic combustion of VOCs.

Achieving efficient toluene mineralization over ordered porous LaMnO3 catalyst: The synergistic effect of high valence manganese and surface lattice oxygen