Surface Dopants‐Induced Interfacial Bonding Greatly Enhances Active Phase‐Support Interaction of Sintering‐Resistant Catalyst for Automotive CO Oxidation

Abstract

Supported nanoparticle catalysts are widely used to remove CO pollution in automobile emission control. During vehicle use, catalysts need to experience high-temperature environments, leading to sintering of active phase and loss of activity. Synthesizing cost-effective catalysts with simultaneously high catalytic activity and sintering resistance is of great importance but remains challenging. In this study, we show that Cu phase supported on commercial antimony-doped tin oxide (ATO) is relatively resistant to sintering and can operate at temperatures below 200 °C without any performance degradation after high temperature aging. Specifically, T 50 (the temperature of 50 % conversion) of CO conversion over the Cu/ATO sample is maintained at 148 °C before and after high-temperature aging treatment at 800 °C. The strong active phase-support interac-tions could be used to stabilize Cu active phase by taking advantage of extra interfacial bonding stability between Cu islands and surface antimony dopants in ATO, and finally tune activity and stability of the catalysts. The Cu-on-ATO ensemble shows excellent resistance against sintering, with conversion efficiency remaining nearly unchanged upon high-temperature aging at 800 °C for 2 to 10 h. In contrast, strong sintering resistance characteristic of catalysts cannot be attained by supporting Cu on undoped tin oxide (SnO 2 ) or conventional Al 2 O 3 due to absence of specific anchoring sites on the support oxide surfaces. Our findings open up the path in heterogeneous catalysis for the design of active and sintering-resistant catalysts utilizing surface engineering strategies.