Surface Reactive Oxygen from Support Corrects the Nominal Supported Metal Size Effect in Controlling the Reactivity for Low-Temperature CH<sub>4</sub>/CO<sub>2</sub> Reforming
Hui Wang, Yansu Hu, Yongli Shen, Ewa Chukwu, Wei Xi, Gurong Shen, Jun Wang, Meiqing Shen, Ming Yang, Tong‐Bu Lu
Abstract
Modulating the metal–support interfacial structure to achieve coke elimination is highly desired for low-temperature CH 4 /CO 2 reforming. Nonetheless, explicit effects of optimizing the supported metal size and catalyst support properties remain convoluted and sometimes controversial. Herein, we designed different Pt–CeO 2 interfaces by tuning the surface reactive oxygen (SRO) from ceria and the in situ aggregated nanoparticle size developed from single-atom Pt as independent parameters. Intriguingly, the often-emphasized nominal Pt size effect (0.3–10.5 nm) is secondary due to carbon deposition, while the catalyst with a high SRO concentration exhibits outstanding reactivity. We demonstrated that the SRO from ceria corrects the nominal supported metal size effect in controlling the low-temperature CH 4 /CO 2 reforming reactivity. Specifically, in the Pt–O x –Ce interfacial microstructure, SRO oxidizes the deposited carbon as an oxygen reservoir, making interfacial Pt atoms remain active from coke, and therefore determines the reactivity rather than the nominal Pt species size. In situ characterizations and theoretical studies explained the reaction mechanism of SRO and carbon elimination. This work provides new insights for coke-resistant catalyst design and the coke elimination mechanism.