Insight into the Synergistic Effect of the Oxide–Metal Interface on Hot Electron Excitation

Formulating a quantitative relationship between the extent of electron transfer at metal–oxide interfaces and catalytic performance aids the rational design of oxide-supported metal catalysts. An effective strategy for monitoring electron transfer at nanoscale interfacial sites is to detect in real time the hot electrons excited when catalytic reactions occur at metal–oxide perimeter sites. Here, based on our in situ techniques for extracting electron transfer as a current signal using a catalytic nanodiode sensor, we observe hot electron excitation at the CeO2/Pt interface during H2 oxidation. By quantitatively analyzing the hot electrons released during the reaction, we identified the optimal concentration of CeO2/Pt interfaces that maximize the catalytic performance of CeO2/Pt. Through a combinatorial study of experiment and theory, we confirm the decisive role of CeO2/Pt interfacial sites in improving the reactivity and electronic excitation.