This work addresses the H-2-deNO(x) reaction representing a prospective tool for the low-temperature NOx abatement under lean conditions. A novel Pd/WOx/ZrO2 catalyst with a W content of 8.7% was developed. The screening of the Pd load performed by temperature-programmed reaction on a laboratory bench provided highest efficiency at a Pd content of 0.41% (0.41Pd/W/ZrO2). This catalyst showed considerable H-2-deNO(x) activity between 125 and 280 degrees C with an outstanding overall N-2 selectivity of 96%. Drastically higher performance was observed when 0.41Pd/W/ZrO2 was evaluated under steady-state conditions resulting in 90% deNO(x) at 160 degrees C and a space velocity of 80,000 h(-1). At this temperature, the apparent turnover frequency of Pd amounted to 8.1 x 10(-5) s(-1), which was very close to that of Pt existing in the highly active Pt/W/ZrO2 system. The variation of the H-2 and O-2 feed concentration indicated that growing H-2 led to increasing H-2-deNO(x) performance accompanied by decreasing N-2 selectivity. O-2 did not affect the selectivity, but clearly limited the operation window of the catalyst at O-2 contents above 6 vol.%. The presence of H2O as well as hydrothermal exposure at 750 degrees C declined both activity as well as N-2 selectivity. The characterisation of the 0.41Pd/W/ZrO2 catalyst by XRD. HRTEM/EDX and XPS showed tetragonal ZrO2, whilst tungsten likely exists in sub-monolayer WOx entities as well as amorphous WO3 nanoparticles. Pd was predominately present in the form of PdO with particle sizes below 2 nm. Mechanistic studies conducted by DRIFT spectroscopy indicated that the lean H-2-deNO(x) reaction 0.41Pd/W/ZrO2 occurs on the Pd sites. The reaction is considered to follow the mechanism according to Burch implying pre-reduction of the active sites by H-2 followed by NO dissociation and formation of N-2 with minor production of N2O. However, some participation of NOx species located on the W/ZrO2 substrate cannot be ruled out completely. (c) 2012 Elsevier B.V. All rights reserved.