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Current NOx emission reduction systems, selective catalytic reduction (SCR) and NOx storage and reduction (NSR), function well after achieving their operation temperature (typically ca. 250 °C) but have unsatisfactory NOx conversion at lower exhaust temperatures encountered during cold start and low load operation. The reduced exhaust temperature of advanced diesel engines with higher fuel efficiency challenges the low-T NOx reduction. We report here a new concept of high low-T deNOx efficiency of up to 80% at a feed temperature of ca. 200 °C at relevant space velocities (70k h−1). It utilizes high-frequency hydrocarbon pulsing on a dual-layer LNT-SCR monolithic catalyst under lean conditions. This system has the potential to expand the operating temperature window of the conventional deNOx devices.