Fabrication of Magnetic Core–Shell CZ/Fe₃O₄ Catalysts for Catalytic CO-SCR

Transition metal catalysts exhibit great promise for application in the field of CO-SCR owing to their exceptional performance and cost effectiveness. The metal oxides generated by traditional synthesis methods often have irregular morphology and small pore sizes, leading to the problems of uneven loading and difficult recycling. Hence, we utilized a two-step hydrothermal methodology to fabricate CexZr1–xO2/Fe3O4 hollow core–shell structured nanocomposites with a high specific surface area and robust paramagnetic properties. These nanostructures exhibit exceptional efficacy in simultaneous elimination of NO and CO. Catalysts with varying molar ratios of Ce/Zr were introduced, resulting in diverse Ce3+/Ce4+ and Fe2+/Fe3+ ratios, abundant oxygen vacancies, and exceptional reducibility, in which the Ce0.7Zr0.3O2/Fe3O4 catalyst achieves 100% NO conversion at 300 °C because it has a large specific surface area, abundant oxygen vacancies, and active sites. In addition, in situ DRIFTS analysis of the samples before and after the magnetization treatment showed that the magnetic field promoted NO adsorption