The present study aims to investigate a Pd catalyst on a complex multi-oxide medium-entropy support interlayer La2O3-CeO2-ZrO2-Al2O3 and its possible use as catalysts for methane abatement applications. The low-temperature N2-adsorption, XRD, TEM, XPS, TPD, and TPR techniques were used to characterize the catalyst. The palladium deposition on the supports leads to the formation of PdO. After the catalytic tests, the metal-Pd phase was observed. The complete oxidation of methane on Pd/La-Ce-Zr-Al catalyst takes place at temperatures above 250 ◦C, and in the presence of water vapor, the reaction temperature increases to about 70 ◦C. The careful choice of constituent oxides provides a balance between structural stability and flexibility. The alumina and lanthanum oxide ensure the high specific surface area, while the simultaneous presence of zirconia and ceria leads to the formation of a mixed-oxide phase able to interact with palladium ions by incorporating and de-incorporating them at different conditions. The mechanism of Mars–van Kerevelen was considered as the most probable for the reaction of complete methane oxidation. The possibility of the practical application of Pd-modified La-Ce-Zr-Al catalyst is evaluated. The use of a mix of multiple rare and abundant oxides makes the proposed catalyst a cost-effective alternative.
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