Relationship between design strategies of commercial three-way monolithic catalysts and their performances in realistic conditions

[Display omitted] •Limited amount of Pd and dopants is required to optimize oxidative properties.•NO reduction is favored with higher Rh concentration.•Ce-Zr-Al distributions play a major role in OSC and catalytic activity.•Ba sulfates has even a limited or negative impact on performances.•Cost/effectiveness should be carefully considered in catalytic formulation strategy. Monolith-shaped three-way catalysts (TWC) are always at the edge of science and technology as a response to the stringent updates on the emission standards worldwide. In spite of rapid research on TWC materials, the exact compositions adapted by major automotive companies are not fully known. This study focuses on comparing two fresh commercial monolithic catalysts for gasoline engines, namely, monolith-A and monolith-B, to highlight the significance of their manufacturing strategies by its characterization and catalytic evaluation under realistic lean/rich/stoichiometric regimes. Firstly, monolith-A demonstrates a zoning on its front and back side with high Pd and Rh loading to enhance CO/HC oxidation and NOx reduction, respectively, having higher amounts of trace dopants like La, Y, Pr and S. Whereas, monolith-B has a homogeneous composition with much lower noble metal/trace elements content without any Pr and S. Secondly, the double-layer washcoating is employed by following different routes with distinct compositions of alumina and ceria-zirconia. Monolith-B showed better low temperature CO oxidation performance while monolith-A performed better for NOx reduction owing to higher Rh loading. Overall, the zoning strategy of monolith-A raises question on its cost effectiveness in regards to its performance while poor reduction capabilities is exhibited by monolith-B. This study highlights that the latest TWC strategies have a scope of further development particularly with respect to the catalytic performance/expense ratio.