Potassium promoted GdCo catalysts for highly efficient catalytic NO decomposition in presence of impurity gases at low temperature.

In order to enhance the catalytic performance of the Gd-modified CoO catalyst (GdCo) for the NO decomposition, alkali metal K was introduced as the promoter by impregnating the GdCo powder with an aqueous solution of KNO (with K/Co ratios 0.01-0.05). With the doping of K, the catalytic activity over GdCo was significantly improved and the temperature of NO complete decomposition was decreased from 350 °C to 300 °C. Combining the results of XPS and O-TPD, the superior catalytic performance of the optimum catalyst KGdCo was mainly owing to the synergistic effect of Gd and K, which weakened the Co-O bond and endowed the catalyst surface with much more amount of oxygen vacancies. Even under the coexist of the impurity gases, such as 5 vol% O, 100 ppmv NO and 2 vol% HO, the KGdCo catalyst exhibited prominently better catalytic activity than GdCo and KCo catalysts.