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Volatile organic compounds （VOCs） emitted from industrial and transportationactivities are harmful to the atmosphere and human health. Therefore, it is highlyurgent to strictly control the emission of VOCs. Catalytic oxidation is one of the mosteffective pathways to eliminate VOCs, in which the key issue is the availability ofeffective catalysts. Perovskite-type oxides exhibit higher catalytic activities andstability, and can be used to catalyze the oxidative removal of VOCs.Three-dimensionally ordered macroporous （3DOM） perovskite-type oxides possesshigher surface areas that are expected to show good catalytic performance in theoxidation of VOCs. With3DOM materials as support, one can prepare their supportedtransition-metal oxide and gold catalysts. With the aid of the strong interactionbetween the metal and support, the catalytic activity and stability can be improved.Therefore, preparing3DOM-structured perovskite-type oxide-supported transition-metal oxide and nanosized gold catalysts and elucidating the relationship between thephysicochemical properties and catalytic performance of the materials are ofacademic and practical significance. In this thesis, we adopted the in situ poly（methylmethacrylate）（PMMA） microsphere-templating and gas bubble-assisted polyvinylalcohol-protected reduction methods to prepare x wt%Co3O4/3DOM La0.6Sr0.4CoO3（x=010） and xAu/LaCoO3（x=1.547.63wt%） catalysts, respectively. Thephysicochemical properties of the materials were characterized by means of thetechniques, such as X-ray diffraction （XRD）, scanning electron microscopy （SEM）,transmission electron microscopy （TEM）, selected-area electron diffraction （SAED）,nitrogen adsorption-desorption （BET）, inductively coupled plasma atomic emissionspectroscopy （ICP-AES）, X-ray photoelectron spectroscopy （XPS）, and hydrogentemperature-programmed reduction （H2-TPR）. The catalytic activities of the sampleswere evaluated for the oxidation of toluene, and their kinetic parameters werecalculated. The main results obtained in the thesis are as follows:1. x wt%Co3O4/3DOM La0.6Sr0.4CoO3（LSCO; x=0,2,5,8, and10） were fabricatedby adopting the in situ PMMA-templating strategy with the metal nitrates as metalsource, L-lysine as surfactant, ethylene glycol and methanol aqueous solution assolvent, in which the3DOM LSCO and Co3O4possessed the rhombohedralperovskite and cubic structures, respectively; the as-prepared x wt%Co3O4/3DOMLSCO samples displayed a macropore size of120140nm, a macropore thicknessof1325nm, and a surface area of3032m2/g. The8wt%Co3O4/3DOM LSCOcatalyst showed the higher oxygen adspecies concentration and betterlow-temperature reducibility. Under the conditions of toluene concentration=1000ppm, toluene/O2molar ratio=1/400, and space velocity （SV）=20,000mL/（g h）, x wt%Co3O4/3DOM LSCO catalysts performed well in the oxidation of toluene,with the8wt%Co3O4/3DOM LSCO catalyst exhibiting the best performance: at aSV of20,000mL/（g h）, the T10%, T50%, and T90%（corresponding to the reactiontemperatures at toluene conversion=10,50%, and90%） were158,210, and227oC, respectively. The apparent activation energies （4358kJ/mol） of the x wt%Co3O4/3DOM LSCOcatalysts were lower than those （5967kJ/mol） of the8wt%Co3O4/bulk LSCO and bulk LSCOcatalysts. Therefore, it is concluded that theexcellent catalytic performance of8wt%Co3O4/3DOM LSCO was associated withits higher oxygen adspecies concentration and better low-temperature reducibility.2.3DOM LaCoO3was prepared using the PMMA-templating method with the metalnitrates as metal source, L-lysine as surfactant, and ethylene and methanol aqueoussolution as solvent. xAu/3DOM LaCoO3（x=1.547.63wt%） were generated viathe gas bubble-assisted PVA-protected reduction route with HAuCl4as Au sourceand NaBH4as reducing agent. The as-prepared LaCoO3and gold showed therhombohedral perovskite and cubic structures, respectively. The xAu/3DOMLaCoO3samples displayed a macropore size of118135nm, a macropore wallthickness of1124nm, an Au particle size of410nm, and a surface area of2429m2/g. The7.63Co3O4/3DOM LaCoO3catalyst showed the higher oxygen adspeciesconcentration, better low-temperature reducibility, stronger interaction between theAu nanoparticles and3DOM LaCoO3. Under the conditions of tolueneconcentration=1000ppm, toluene/O2molar ratio=1/400, and SV=20,000mL/（gh） or CO concentration=1vol%, CO/O2molar ratio=1/20, and SV=10,000ml/（g h）, the xAu/3DOM LaCoO3catalysts performed excellently in the oxidation oftoluene and CO. The7.63Co3O4/3DOM LaCoO3catalyst exhibited the highestactivity: the T10%, T50%, and T90%were136,188, and202oC for toluene oxidation,and61,6, and42oC for CO oxidation, respectively. The apparent activationenergies （31.438.6kJ/mol） of the3DOM LaCoO3and xAu/3DOM LaCoO3catalysts were lower than those （49.761.5kJ/mol） of the bulk LaCoO3and7.56Au/bulk LaCoO3catalysts for toluene oxidation, and the apparent activationenergies （16.619.4kJ/mol） of the xAu/3DOM LaCoO3catalystswere also lowerthan those （22.829.3kJ/mol） of the bulk LaCoO3和7.56Au/bulk LaCoO3catalysts.Therefore, we believe that the higher oxygen adspecies concentration, betterlow-temperature reducibility, and strong Au3DOM LaCoO3interaction of7.63Au/3DOM LaCoO3was responsible for its excellent catalytic performance fortoluene and CO oxidation.
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