▎ 摘　　要

Three-dimensional graphene (3DG) was prepared from watermelon red flesh by hydrothermal method, and the catalysts CeCoO delta/3DG, CeCuO delta/3DG, and CeCoxCu1 - O-x(delta)/3DG were prepared by co-precipitation method. Their NH3-SCR activity, N-2 selectivity, and stability were tested. The results suggested that CeCo0.5Cu0.5O delta/3DG showed the best denitrification activity at low temperature, which NOx conversion was close to 90% at 250 degrees C, and all the catalysts had good stability and >99% N-2 selectivity. XRD, Raman, SEM, TEM, SEM mapping, XPS, H-2-TPR, and other technical means were used to preliminarily explore the internal mechanism of enhancing the NH3-SCR activity for ternary composite metal oxide catalysts. At low temperatures, the CeCo0.5Cu0.5O delta/3DG catalyst has the greatest catalytic activity. It is because that the introduction of the third metal facilitates the migration of lattice oxygen O-beta to adsorbed oxygen O-alpha, which enhances the oxidation capacity of the catalyst. At the same time, the reduction peak of metal oxides migrates to low temperature, which enhances the low temperature reduction ability of the catalyst.