DFT plus U analysis of the stability of Pdn/CeO2-d ( n=3, 4)

Transition metals supported over CeO2 surfaces have attracted wide attention of materials researchers because of their vital applications in catalysis. CeO(2)as a support is known to stabilise transition metal nanoparticles or clusters on its surface preventing the loss of their catalytic activities. To probe the reasons behind the stability of Pd-3 and Pd-4 clusters over CeO2(111) and (110) surfaces with and without vacancy defects, we employed DFT calculations in this study. Our analysis revealed the effect of the vacancy defects to be marginal on the binding of the clusters over the studied surfaces. However, surface diffusion barriers were significantly altered by the presence of vacancies. Our investigation highlighted pristine CeO2(110) and sub-surface vacancy defected CeO2(111) surfaces as excellent materials providing good binding and high surface diffusion barriers for the localised binding of Pd3 and Pd4 clusters.