An ultrastable heterostructured oxide catalyst based on high-entropy materials: A new strategy toward catalyst stabilization via synergistic interfacial interaction

[Display omitted] •A heterostructured catalyst based on high–entropy material was prepared.•Cu species in HEO dissolved into CeO2 via an entropy-driven mechanochemical process.•The heterostructure was between high–entropy oxides and CeCuOx.•The heterostructured catalyst showed high-temperature stability for CO oxidation. Designing high-performance catalysts that can stabilize catalytic active sites against sintering to deactivation at temperature higher than 900 °C is significant but challenging. Here we report a new strategy to obtain a transition metal oxide catalyst with high temperature stability for CO oxidation. This is achieved through a synergistic interfacial interaction at the interface of a heterostructure between high–entropy oxides (HEO, high temperature stability) and CuCeOx (catalytic site). The catalytic site (CuCeOx) for CO oxidation is realized by dissolving an amount of Cu species in HEO into CeO2 via an entropy–driven mechanochemical process. In situ XRD and HAADF–STEM have confirmed the high temperature stability of the heterostructure CuCeOx–HEO, which can remain its CO oxidation catalytic activity at elevated temperatures. It should be expected that this innovative will offer the potential to the synthesis of catalysts with high temperature stability in industry.