Room-temperature degradation of o-xylene in simulated air using an online-regenerable plasma-catalysis reactor with low amounts of nanosized noble metals on Co₃O₄

The plasma catalytic degradation of o-xylene in simulated air was improved by loading low amounts of Pt, Pd, or Au onto Co₃O₄. At room temperature, o-xylene conversion and CO_x selectivity using a 0.1 wt% Pt/Co₃O₄ catalyst reached 98.9% and 80%, and the energy efficiency was at the top level in comparison with values in the literature. A stable o-xylene degradation performance could be obtained by online regenerating the heat-insulated reactor with a high energy density. After characterization, it was found that the loading of nanosized Pt not only increased the Co³⁺/Co²⁺ ratio, where the Co³⁺ benefitted the formation of reactive oxygen species, but also conduced Pt⁰ to oxygen activation, resulting in effective promotion of complete o-xylene oxidation. Operando plasma diffuse reflectance infrared Fourier transform spectroscopy demonstrated the complete o-xylene oxidation and proved that Pt played a key role in the complete oxidation of o-xylene.