Regulating Heteroatom Doping-Induced Embedded Pt-M Bimetallic Sites Coupled with Ce3+-OVs for Efficient Low-Temperature Methanol Steam Reforming

Abstract

Platinum-based metal oxide catalysts confront huge challenges in achieving efficient low-temperature methanol steam reforming below 200 °C. Here, the highly dispersed metal (M) dopants coordinated with embedded Pt species at Pt-CeM (110) interface is exploited. This arrangement shortens the geometric distance between embedded Pt and doped M atoms, enabling Pt-M coordination and facilitating the formation of atomically dispersed Pt-M bimetallic sites on the catalyst surface. This unique structure promotes electron transfer across interfaces, intensifying Pt-support interactions that enhanced methanol decomposition. Meanwhile, enhanced hydrogen spillover forms Ce³⁺-OVs pairs (where OV denotes an oxygen vacancy) at the hydrogen activation stage, which promotes H₂O dissociation. Thus, the proposed mechanisms suggest the formation of dual-function centers consisting of Pt–M and Ce³⁺-OVs, which facilitated methanol decomposition and H₂O dissociation, respectively. This process involved successive dehydrogenation of methanol followed by WGS reaction via the *CO route, with the rate-determining step of *CO + *OH → *COOH being enhanced based on DFT calculations. The optimal Pt-CeCo (H₂) catalyst exhibited an extremely low start-up temperature of 140 °C and a remarkable H₂ production rate below 200 °C. This study presents an approach for synthesizing atomically dispersed bimetallic active sites with strong interfacial interactions, leading to the development of an efficient catalytic system for low-temperature methanol reforming.