Promotion effect of alkaline leaching on the catalytic performance over Cu/Fe-SSZ-13 catalyst for selective catalytic reduction of NOx with NH3

•A novel strategy for synthesizing high-performance SCR catalyst was proposed.•Base leaching can improve the NH3-SCR activity of the Cu/Fe-SSZ-13 catalyst.•Fine control of base leaching process is beneficial to the formation of Cu2+−2Z.•A plausible promoting mechanism of base leaching on deNOx performance was proposed.