PdIn-Based Pseudo-Binary Alloy as a Catalyst for NO<i>_<i>x</i></i> Removal under Lean Conditions

Abstract

Developing a noble-metal-based catalyst that works effectively for NOx removal in the presence of excess O2 is still a big challenge in catalytic chemistry for exhaust gas purification. To overcome this challenge, in this study, we designed and prepared a nanoparticulate (Pd1–xPtx)In pseudobinary alloy using Al2O3 and CeO2 supports, where a portion of Pd was replaced with Pt to improve the oxidation tolerance of In during NOx reduction under lean conditions. Multiple characterization techniques were used to confirm the formation of the desired pseudobinary alloy phase. The prepared Pd–Pt–In/CeO2 catalyst exhibited high NO conversion to N2 in NO–CO–O2 reaction with a wide range of oxygen concentrations including lean conditions (80%–100%, 0.75 ≤ λ ≤ 1.5, 350 °C) and retained its catalytic performance during rich–lean cycles.