Adsorption of ammonia (NH3) on palladium oxide (PdO) surface (001): Ab initio study

[Display omitted] •NH3 adsorptions on the PdO(001) surface were examined.•Most stable adsorption site was performed.•PdO(001)-Pd adsorption energies are greater than those of PdO(001)-O.•PDOS of the NH3/PdO(001) system was analyzed.•Thermochemistry of NH3 dissociation was investigated. Dacapo code with the GGA-PW91 approximation has been used to study the adsorption of ammonia molecular (NH3) on PdO(001) termination surfaces, via N atom. We have determined the geometrical parameters of NH3 in the free phase, the PdO mesh parameters, at different sites of PdO(001) surface, the adsorption energies, the geometrical parameters of NH3 in adsorbed phase, the PDOS of the system, as well as the decomposition. The hollow (H) site of the PdO-O(001) termination is found to be most energetically stable with an adsorption energy of −0.445 eV, while the bridge-oy (B2) site of the PdO-Pd(001) termination is the most energetically stable with an adsorption energy of −1.105 eV. The isosurface calculations of NH3/PdO(001) show an accumulation of charges around the nitrogen, oxygen and palladium atoms, and charge depletion for hydrogen atoms. The thermochemistry of NH3 is very favourable on the PdO-O(001) surface, however for the PdO-Pd(001) surface the last two reaction paths are unfavourable. Finally, all the obtained results are in agreement with those found in the literature.