  Development of novel materials may often require a rational use of high price
components, like noble metals, in combination with the possibility to tune
their properties in a desirable way. Here we present a theoretical DFT study of
Au and Pd single atoms supported by doped MgO(001). By introducing B, C and N
impurities into the MgO(001) surface, the interaction between the surface and
the supported metal adatoms can be adjusted. Impurity atoms act as strong
binding sites for Au and Pd adatoms and can help to produce highly dispersed
metal particles. The reactivity of metal atoms supported by doped MgO(001), as
probed by CO, is altered compared to their counterparts on pristine MgO(001).
We find that Pd atoms on doped MgO(001) are less reactive than on perfect
MgO(001). In contrast, Au adatoms bind CO much stronger when placed on doped
MgO(001). In the case of Au on N-doped MgO(001) we find that charge
redistribution between the metal atom and impurity takes place even when not in
direct contact, which enhances the interaction of Au with CO. The presented
results suggest possible ways for optimizing the reactivity of oxide supported
metal catalysts through impurity engineering.
