Ag nanoparticles in a Yb2O3 matrix catalyzed the direct decomposition of N2O to the elements. Our investigations included X-ray powder diffraction and electron microscopy; they revealed a remarkable dependence of the catalytic activity on the catalyst preparation method that influenced the size of Ag crystallites. Simple precipitation followed by calcination resulted in the formation of a catalyst with rather large Ag crystallites, which showed low activity. In contrast, thermal decomposition of the mixed-metal Ag-Yb coordination polymer provided the Ag/Yb2O3 catalytic system with distinctly smaller Ag crystallites. The coordination-polymer derived catalyst exhibited much higher activity in the deN(2)O process at moderate temperature range 400-500 degrees C. (C) 2016 Elsevier B.V. All rights reserved.