Effect of Metal Loading and Carbon Support Microstructure on the Dispersion of Pt/C Catalysts Prepared via Adsorption of Chloroplatinic Acid
Reaction Kinetics and Catalysis Letters
, E-ISSN: 1588-2837
||Active carbon, Carbon black, Carbon microstructure, Platinum dispersion, Pt/C catalysts, Sibunit
Kholodovich Alesya N.
Simonov Pavel A.
Boreskov Institute of Catalysis, Novosibirsk 630090, Russia
Adsorption of H2PtCl6 onto a carbon support followed by reduction of the adsorbed platinum species with H2 at 250°C leads to Pt/C catalysts, which show universal volcano-like dependence of platinum dispersion on the metal loading in the range from 0.01 to 0.55 mmol (Pt)/m2 (SBET) when highly disordered carbons, namely, active carbons and carbon blacks, are used as supports. The maximal dispersion D(CO/Pt) = 0.8 is attained at 0.18 mmol (Pt)/m2 (SBET). With other factors being equal, the dispersion of platinum supported on carbons with a more regular crystal structure, especially Sibunit-type supports, proves to be the highest and independent of the metal loading.The differences between the two groups of carbon supports are explained by the differences in the state of the adsorbed platinum precursors.