Formation of platinum sites on layered double hydroxide type basic supports: III. Effect of the mechanism of [PtCl6](2-) complex binding to aluminum-magnesium layered double hydroxides on the properties of supported platinum in Pt/MgAlO (x) catalysts

摘要

While synthesizing platinum catalysts supported on aluminum-magnesium oxides (Pt/MgAlO (x) ), we established that, in the binding of the Pt(IV) chloro complex to aluminum-magnesium layered double hydroxides (LDHs), the mechanism of the metal complex-support interaction depends on the nature of the interlayer anion of the LDH. The synthesis may yield chemically identical Pt/MgAlO (x) samples differing in the particle size and electronic structure of supported platinum. The higher dehydrogenating activity of the catalyst obtained by binding the [PtCl6](2-) complex in the interlayer space of LDH via exchange with interlayer OH- anions is possibly due to the larger proportion of metallic platinum (Pt-0) in this catalyst. In the catalyst prepared from hydrolyzed platinum complex species using LDH with CO (3) (2-) interlayer anions, platinum is mainly in an oxidized state similar to Pt2+.