Spinel dual-metal sites synergy and zeolite confinement effect: CuFe2Ox/SSZ-13 achieves high N2 selectivity in n-butylamine oxidation via SCO-SCR coupling.

To balance catalytic activity and N2 selectivity in the oxidation of nitrogen-containing volatile organic compounds (NVOCs), a dual-metal-site catalyst supported on CHA zeolite (CuFe2Ox/SSZ-13) was prepared via a simple impregnation method. Utilizing the strong interfacial and confinement effects between spinel and SSZ-13, the catalyst exhibited excellent n-butylamine (NBA) oxidation performance (T50＜150℃, T90=210℃) and high N2 selectivity (98% at 440°C), owing to the coupled selective catalytic oxidation (SCO) and selective catalytic reduction (SCR) of intermediates. Physicochemical characterization and DFT calculations clarified the distinct roles of the Cu and Fe sites and the synergistic mechanism of O species. This work provides a new effective strategy to design efficient NVOCs-SCO catalysts through the targeted selection of metals at the A/B sites of spinel.