Role of the Mg/Al atomic ratio in hydrotalcite-based catalysts for NOx storage/reduction
Source abstract
Abstract
Abstract 1.0 wt.% Pt supported catalysts were prepared by incipient wetness impregnation of Mg–Al supports obtained by thermal decomposition of commercial hydrotalcite-type (HT) precursors with different Mg/Al atomic ratios (1.3, 2.0 and 3.0, respectively) and investigated in the storage–reduction of NOx (NSR). These catalysts showed improved performances in comparison to a Toyota-type Pt–Ba/Al2O3 catalyst at temperatures ≤ 250 °C. This behaviour can be attributed to the formation of well-dispersed cubic Mg(Al)O mixed oxides, which showed good NOx-storage properties, significantly better than those of the stoichiometric spinel MgAl2O4. Both the catalytic activity and the stability after a hydrothermal treatment of Pt/HT catalysts increased by increasing the Mg/Al atomic ratio, while the analogous Pt/MgO catalyst deactivated almost completely, evidencing the key role of the HT precursor.
Source: openaire · Quality: candidate unverified · Source record ↗
Research context
OpenAlex topics: Layered Double Hydroxides Synthesis and Applications · Microwave Dielectric Ceramics Synthesis · Thermal Expansion and Ionic Conductivity
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
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